Abstract

Calibrating an unstable sensor of a mobile device. Systems and methods for calibrating a sensor of a mobile device determine a first estimated position of the mobile device without using any measurement from the sensor of the mobile device, generate a second estimated position of the mobile device using a measurement from the sensor, estimate a sensor error of the sensor using the first estimated position and the second estimated position, and use the sensor error to determine a calibration value for adjusting one or more measurements from the sensor.

IPC Classes  ?

• G01C 17/38 - Testing, calibrating, or compensating of compasses
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 21/10 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration
• G01C 21/16 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01S 19/14 - Receivers specially adapted for specific applications

Abstract

Calibrating weather stations using maximum allowed altitude errors. Particular embodiments described herein include machines that determine a maximum allowed pressure calibration error for a weather station, determine a temperature variation associated with an environment in which the weather station resides, determine a maximum allowed altitude error for the weather station using the maximum allowed pressure calibration error and the temperature variation, and use the maximum allowed altitude error to determine if a first maximum possible altitude error associated with a first approach for estimating an altitude of the weather station exceeds the maximum allowed altitude error. If the first maximum possible altitude error associated with the first approach does not exceed the maximum allowed altitude error, the first approach is used to estimate an altitude of the weather station for use in calibrating a pressure sensor of the weather station.

IPC Classes  ?

• G01W 1/18 - Testing or calibrating meteorological apparatus
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

Multiple calibration results for calibrating a barometric pressure sensor based on data received from a device containing the sensor are determined and stored in a table. The table is updated based on rules regarding a relationship between each calibration result and a current calibration value. The calibration results are weighted and combined to determine a combined calibration result. The calibration value for calibrating the sensor is selected from the calibration results, the combined calibration results, or the current calibration value based on a selection criteria.

IPC Classes  ?

• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

Calibrating weather stations using maximum allowed altitude errors. Particular embodiments described herein include machines that determine a maximum allowed pressure calibration error for a weather station, determine a temperature variation associated with an environment in which the weather station resides, determine a maximum allowed altitude error for the weather station using the maximum allowed pressure calibration error and the temperature variation, and use the maximum allowed altitude error to determine if a first maximum possible altitude error associated with a first approach for estimating an altitude of the weather station exceeds the maximum allowed altitude error. If the first maximum possible altitude error associated with the first approach does not exceed the maximum allowed altitude error, the first approach is used to estimate an altitude of the weather station for use in calibrating a pressure sensor of the weather station.

IPC Classes  ?

• G01W 1/18 - Testing or calibrating meteorological apparatus
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

A method involves selecting a set of altitude envelope distribution constraints for a building and generating a set of altitude envelope distributions for the building in accordance with the constraints. Each altitude envelope distribution includes one or more first altitude envelopes. An aggregate altitude envelope distribution is generated for the building using the set of altitude envelope distributions and in accordance with the constraints. The aggregate altitude envelope distribution includes one or more second altitude envelopes. A reference altitude of the building is determined, and an absolute aggregate altitude envelope distribution is determined using the reference altitude and the aggregate altitude envelope distribution. The aggregate altitude envelope distribution includes one or more third altitude envelopes, each corresponding to a respective estimated floor number of the building.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 21/20 - Instruments for performing navigational calculations

Abstract

Calibrating a pressure sensor of a mobile device includes determining a first plurality of calibration values for a first plurality of visits to a first revisit zone to which a mobile device repeatedly returns; determining a first relative calibration adjustment value based on the first plurality of calibration values; determining an adjusted absolute calibration value based on i) an absolute calibration value used to calibrate pressure measurements made by a pressure sensor of the mobile device, and ii) the first relative calibration adjustment value; and calibrating pressure measurements made by the pressure sensor of the mobile device using the adjusted absolute calibration value.

IPC Classes  ?

• G01C 17/38 - Testing, calibrating, or compensating of compasses
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01C 21/16 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
• G01S 19/14 - Receivers specially adapted for specific applications
• G01C 21/10 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration

Abstract

A method involves determining weighted metric values for each metric of a plurality of metrics by applying a weight for each metric to a determined value of each metric. The method further involves using the weighted metric values to determine if a pressure sensor of a mobile device should be calibrated using information associated with the first location, and if a determination is made that the pressure sensor of the mobile device should be calibrated using information associated with the first location, then using the information associated with the first location to calibrate the pressure sensor of the mobile device.

IPC Classes  ?

• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• G01L 19/00 - MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE - Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges

Abstract

Determining one or more heights of one or more mobile devices above surfaces. Particular embodiments described herein include machines that retrieve first data (e.g., measurement value(s) determined by sensor(s) of a mobile device or estimated position(s) of the mobile device), determine a location context based on the first data, identify second data (e.g., measurement value(s) determined by sensor(s) of the mobile device or status indicator value(s) of feature(s) of the mobile device) to retrieve for use in determining an estimated height above a surface at which the mobile device is located based on the determined location context, retrieve the second data, and determine an estimated height above a surface at which the mobile device is located based on the retrieved second data.

IPC Classes  ?

• H04M 1/72454 - User interfaces specially adapted for cordless or mobile telephones with means for adapting the functionality of the device according to specific conditions according to context-related or environment-related conditions
• H04W 4/029 - Location-based management or tracking services
• H04W 4/16 - Communication-related supplementary services, e.g. call-transfer or call-hold

Abstract

Systems and methods are described for determining position of a receiver. The positioning system comprises a transmitter network including transmitters that broadcast positioning signals. The positioning system comprises a remote receiver that acquires and tracks the positioning signals and/or satellite signals. The satellite signals are signals of a satellite-based positioning system. A first mode of the remote receiver uses terminal-based positioning in which the remote receiver computes a position using the positioning signals and/or the satellite signals. The positioning system comprises a server coupled to the remote receiver. A second operating mode of the remote receiver comprises network-based positioning in which the server computes a position of the remote receiver from the positioning signals and/or satellite signals, where the remote receiver receives and transfers to the server the positioning signals and/or satellite signals.

IPC Classes  ?

• H04B 1/7087 - Carrier synchronisation aspects
• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• H04W 72/30 - Resource management for broadcast services
• H04W 72/51 - Allocation or scheduling criteria for wireless resources based on terminal or device properties
• G01S 19/46 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement the supplementary measurement being of a radio-wave signal type
• G01S 5/10 - Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements
• G01S 1/08 - Systems for determining direction or position line
• G01S 19/24 - Acquisition or tracking of signals transmitted by the system
• G01S 19/42 - Determining position
• H04B 7/26 - Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
• H04W 72/0446 - Resources in time domain, e.g. slots or frames
• H04B 1/709 - Correlator structure

Abstract

Device-based barometric pressure sensor calibration involves determining a specific location of the mobile device; determining a general location of the mobile device that encompasses and obfuscates the specific location; transmitting the general location to a server; receiving general calibration data for the general location; determining specific calibration data based on the general calibration data and the specific location; determining a calibration value based on the specific calibration data, the calibration value being for calibrating the barometric pressure sensor.

IPC Classes  ?

• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

Determining calibration values for atmospheric sensors that provide measured pressures used for estimating altitudes of mobile devices. Particular systems and methods determine if any uncalibrated reference-level pressure estimates associated with an unstable pressure sensor should not be used when calibrating the unstable pressure sensor, and calibrate the unstable pressure sensor using all of the uncalibrated reference-level pressure estimates except any uncalibrated reference-level pressure estimate that should not be used when calibrating the unstable pressure sensor.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• H04W 4/029 - Location-based management or tracking services
• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure

Abstract

Embodiments describe determining position by selecting a set of digital pseudorandom sequences. The magnitudes of the cross-correlation between any two sequences of the chosen set are below a specified threshold. A subset of digital pseudorandom sequences are selected from the set such that the magnitudes of the autocorrelation function of each member of the subset, within a specified region adjacent to the peak of the autocorrelation function, are equal to or less than a prescribed value. Each transmitter transmits a positioning signal, and at least a portion of the positioning signal is modulated with at least one member of the subset. At least two transmitters of the plurality of transmitters modulate respective positioning signals with different members of the subset of digital pseudorandom sequences.

IPC Classes  ?

• G01S 19/45 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters

Abstract

Determining contexts of mobile devices. Particular embodiments described herein include machines that determine two estimated positions of a mobile device that respectively correspond to first and second locations at first and second times, acquire sets of terrain or structural information for first and second areas that respectively include the first and second estimated positions, use the acquired sets of information and the estimated positions to determine if the mobile device was near or within a structure at the first and second times, determine one or more values that are indicative of vertical movement by the mobile device during a period of time between the first time and the second time, compare the one or more values to one or more threshold conditions, and determine a context of the mobile device based on the comparison.

IPC Classes  ?

• G06F 3/01 - Input arrangements or combined input and output arrangements for interaction between user and computer
• H04M 1/72457 - User interfaces specially adapted for cordless or mobile telephones with means for adapting the functionality of the device according to specific conditions according to geographic location
• H04M 1/72403 - User interfaces specially adapted for cordless or mobile telephones with means for local support of applications that increase the functionality
• H04M 1/72454 - User interfaces specially adapted for cordless or mobile telephones with means for adapting the functionality of the device according to specific conditions according to context-related or environment-related conditions
• G01P 15/02 - Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces
• G06F 3/041 - Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• H04N 21/45 - Management operations performed by the client for facilitating the reception of or the interaction with the content or administrating data related to the end-user or to the client device itself, e.g. learning user preferences for recommending movies 
• H04W 4/021 - Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences

Abstract

Determining when a barometric-based approach for estimating an unknown altitude of a mobile device should not be used. Different approaches determine if estimating an unknown altitude of a mobile device using a measured atmospheric condition will result in an estimated altitude having acceptable or unacceptable error. If use of the measured atmospheric condition would result in acceptable error, the measured atmospheric condition is used to estimate the unknown altitude. If use of the measured atmospheric condition would result in unacceptable error, the measured atmospheric condition is not used to estimate the unknown altitude. The resultant altitude estimate is then used to locate the mobile device.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01N 33/00 - Investigating or analysing materials by specific methods not covered by groups

Abstract

A method involves identifying multiple calibration values and corresponding calibration confidence values of an initial calibration dataset in which one or more calibration values were derived using an atmospheric pressure measurement from a barometric air pressure sensor of a mobile device. A calibration metric is determined for each calibration value. One or more of the calibration values are filtered out from the initial calibration dataset based on the calibration metric to generate a filtered calibration dataset. A filtered calibration value is determined using the filtered calibration dataset. The barometric air pressure sensor of the mobile device is calibrated using the filtered calibration value.

IPC Classes  ?

• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

An alert indicates that a situation conducive to calibrating a barometric pressure sensor of the user device might have occurred. In response, calibration data is collected for calibrating the barometric pressure sensor. The calibration data is used to perform a calibration process and generate a calibration value for the barometric pressure sensor.

IPC Classes  ?

• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves

Abstract

Multiple calibration results for calibrating a barometric pressure sensor based on data received from a device containing the sensor are determined and stored in a table. The table is updated based on rules regarding a relationship between each calibration result and a current calibration value. The calibration results are weighted and combined to determine a combined calibration result. The calibration value for calibrating the sensor is selected from the calibration results, the combined calibration results, or the current calibration value based on a selection criteria.

IPC Classes  ?

• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

Determining, broadcasting and using reference pressure data in a network of transmitters. Particular embodiments described herein include machines that select atmospheric data from weather stations within a transmitter network, use the selected atmospheric data to determine a reference atmospheric value, and transmit the reference atmospheric value from a transmitter to a mobile device for use in estimating an altitude of the mobile device. The atmospheric data may include any of reference pressures form the weather stations, measured temperatures from the weather stations, or reference temperatures from the weather stations. The reference atmospheric value may include a reference pressure value of a reference altitude, or a reference temperature value.

IPC Classes  ?

• G01W 1/10 - Devices for predicting weather conditions
• H04W 4/029 - Location-based management or tracking services
• G01S 5/00 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01W 1/06 - Instruments for indicating weather conditions by measuring two or more variables, e.g. humidity, pressure, temperature, cloud cover or wind speed giving a combined indication of weather conditions
• H04H 60/71 - Systems specially adapted for using specific information, e.g. geographical or meteorological information using meteorological information
• H04W 4/02 - Services making use of location information

Abstract

A method involves determining an estimated position of a mobile device within a region. Atmospheric data measurement stations are identified within the region. A geographical anomaly is identified within the region that physically intervenes between the mobile device and a first atmospheric data measurement station. Based on a positional relationship between the mobile device, the geographical anomaly, and the first atmospheric data measurement station, it is determined that atmospheric pressure measurements collected at the first atmospheric data measurement station should be conditionally used for determining a reference pressure estimate. The reference pressure estimate is determined using a plurality of atmospheric pressure measurements collected at the atmospheric data measurement stations and conditionally using the atmospheric pressure measurements collected at the first atmospheric data measurement station. An estimated altitude of the mobile device is determined using a measurement of atmospheric pressure at the mobile device and the reference pressure estimate.

IPC Classes  ?

• G01W 1/18 - Testing or calibrating meteorological apparatus
• G06F 7/501 - Half or full adders, i.e. basic adder cells for one denomination

Abstract

Field calibration of a pressure device involves collecting simultaneous pressure data or pressure and temperature data at two devices for multiple time points. Pressure differences between pairs of simultaneous data points of the collected pressure data are calculated. A model is fitted to the pressure differences and the temperatures and/or pressures, and model parameters are used to correct measurements from the second device. Alternatively, a pressure gradient is estimated for a region that encompasses the two devices for each time point. A distance is determined between the two devices. A pressure gradient difference is determined between the two devices for each time point. A pressure difference offset is obtained for one of the pairs of simultaneous data points for each time point. An average pressure difference offset is determined between the two devices and is used to correct measurements from one of the devices.

IPC Classes  ?

• G01W 1/18 - Testing or calibrating meteorological apparatus
• G01W 1/02 - Instruments for indicating weather conditions by measuring two or more variables, e.g. humidity, pressure, temperature, cloud cover or wind speed

Abstract

A method to identify a problematic 2D position of a mobile device can include: determining a reported 2D position of the mobile device; determining a piece of information about the mobile device; and comparing the reported 2D position and the piece of information about the mobile device. Upon determining that the reported 2D position and the piece of information about the mobile device are consistent with each other, the reported 2D position of the mobile device is used as an estimate of the actual 2D position of the mobile device, or upon determining that the reported 2D position and the piece of information about the mobile device are not consistent with each other, the reported 2D position is determined to be problematic, and the reported 2D position of the mobile device is removed from a list of reported 2D positions of the mobile device.

IPC Classes  ?

• H04W 4/029 - Location-based management or tracking services
• H04W 4/02 - Services making use of location information
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

Determining when an estimated altitude of a mobile device can be used for calibration or location determination. Particular systems and methods determine an area in which the mobile device is expected to reside, determine an altitude value of each section of a plurality of sections in the area, determine if the altitude values meet a threshold condition, and determine that the estimated altitude of the mobile device can be used for determining the position of the mobile device or for calibrating a pressure sensor of the mobile device when the altitude values meet the threshold condition.

IPC Classes  ?

• G01C 5/00 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
• G06F 17/18 - Complex mathematical operations for evaluating statistical data
• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• H04W 4/029 - Location-based management or tracking services
• G01S 5/00 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations

Abstract

Pressure-based estimation of a mobile device altitude or calibration of a pressure sensor involves machines that determine if a reference-level pressure value based on one or more measurements of pressure from a network of weather stations should or should not be used to calibrate a pressure sensor of a mobile device or to estimate an altitude of the mobile device. If the reference-level pressure value should be used, the reference-level pressure value is used to calibrate a pressure sensor of a mobile device or to estimate an altitude of the mobile device. If the reference-level pressure value should not be used, a trend in pressure is determined, an estimated reference-level pressure value based on the trend is determined, and the estimated reference-level pressure value is used to calibrate a pressure sensor of a mobile device or to estimate an altitude of the mobile device.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure

Abstract

A calculated current lapse rate is determined for a geographical area that includes a location of a mobile device. The calculated current lapse rate provides an estimated air temperature variation with respect to altitude variation for the location of the mobile device. An altitude of the mobile device is estimated. An uncertainty of the altitude of the mobile device is estimated based on a reference pressure and a reference temperature for a reference plane that is within the geographical area, a device pressure for the mobile device, and the calculated current lapse rate.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass

Abstract

A wholistic activity context is used to determine whether to calibrate a barometric pressure sensor of a mobile device. A pair of activity transitions are determined from three activities of the mobile device. A time relationship and a position relationship between the activity transitions is determined. An opportunity to calibrate the barometric pressure sensor occurs between the activity transitions. A calibration of the barometric pressure sensor is performed in response to determining that the time relationship and the position relationship indicate that the wholistic activity context surrounding the opportunity to calibrate the barometric pressure sensor is conducive to calibration.

IPC Classes  ?

• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

Extending the spatial coverage of a reference pressure network. Particular embodiments described herein include machines that initially determine that an estimated position of a mobile device resides outside a coverage area of a network of reference pressure sensors. Reference-level pressures corresponding to reference pressure sensors of the network are determined using measurements of pressure from the network of reference pressure sensors. A pressure pattern for a region that includes the estimated position and an area not included in the coverage area of the network is determined using reference-level pressures that were not determined using measurements of pressure from the network of reference pressure sensors. The reference-level pressures corresponding to reference pressure sensors of the network and the pressure pattern are used to determine a reference-level pressure value for use in calibrating a pressure sensor of the mobile device or for use in estimating an altitude of the mobile device.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 21/20 - Instruments for performing navigational calculations

Abstract

Estimating a difference in height between floors in a building for use in estimating a height or an altitude of one of the floors. A height difference is estimated between a first floor and a second floor based on outdoor temperatures of first and second time periods, an indoor temperature of the first or second time period, and first and second estimated differences in height between the first and second floors that is based on measurements of pressure from mobile devices when the mobile devices were on the first and second floors during the first and second time periods.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• G01C 21/20 - Instruments for performing navigational calculations

Abstract

A method involves determining, at a mobile device or a service, an uncertainty in height above a reference altitude, an estimated 2D position of the mobile device, and an uncertainty in terrain height above the reference altitude using the estimated 2D position. An uncertainty in height above terrain, of the mobile device, is determined at the mobile device or a server using the uncertainty in height above the reference altitude and the uncertainty in terrain height above the reference altitude.

IPC Classes  ?

• H04W 4/02 - Services making use of location information
• G01S 19/51 - Relative positioning
• G01C 5/00 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels

Abstract

Multiple calibration results for calibrating a barometric pressure sensor based on data received from a device containing the sensor are determined and stored in a table. The table is updated based on rules regarding a relationship between each calibration result and a current calibration value. The calibration results are weighted and combined to determine a combined calibration result. The calibration value for calibrating the sensor is selected from the calibration results, the combined calibration results, or the current calibration value based on a selection criteria.

IPC Classes  ?

• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

Extending the spatial coverage of a reference pressure network. Particular embodiments described herein include machines that initially determine that an estimated position of a mobile device resides outside a coverage area of a network of reference pressure sensors. Reference-level pressures corresponding to reference pressure sensors of the network are determined using measurements of pressure from the network of reference pressure sensors. A pressure pattern for a region that includes the estimated position and an area not included in the coverage area of the network is determined using reference-level pressures that were not determined using measurements of pressure from the network of reference pressure sensors. The reference-level pressures corresponding to reference pressure sensors of the network and the pressure pattern are used to determine a reference-level pressure value for use in calibrating a pressure sensor of the mobile device or for use in estimating an altitude of the mobile device.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 21/20 - Instruments for performing navigational calculations

Abstract

Calibrating a pressure sensor of a mobile device incudes determining an absolute calibration value used to calibrate pressure measurements by a pressure sensor of a mobile device; determining a first revisit zone as a first location to which the mobile device repeatedly returns; determining first and second calibrations for first and second visits to the first revisit zone; determining a first relative calibration adjustment value based on a difference between the first and second calibrations; determining an adjusted absolute calibration value based on a sum of the absolute calibration value and the first relative calibration adjustment value; and estimating an altitude of the mobile device based on a pressure measurement by the pressure sensor and the adjusted absolute calibration value.

IPC Classes  ?

• G01C 17/38 - Testing, calibrating, or compensating of compasses
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01C 21/16 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
• G01S 19/14 - Receivers specially adapted for specific applications
• G01C 21/10 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration
• G01S 19/40 - Correcting position, velocity or attitude

Abstract

Methods and machines involve detecting when a mobile device is in a first area and a second area at different times, collecting pressure data from the mobile device and reference sensor(s) to estimate altitudes of the mobile device within the first area and the second area, collecting terrain altitudes associated with the first area and the second area, and using a difference between the estimated altitudes and a difference between the terrain altitudes to determine a height of a floor. The estimated floor height may be used to calibrate a pressure sensor of a mobile device.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• H04W 4/33 - Services specially adapted for particular environments, situations or purposes for indoor environments, e.g. buildings
• H04W 4/021 - Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences

Abstract

Determining contexts of mobile devices. Particular embodiments described herein include machines that determine two estimated positions of a mobile device that respectively correspond to first and second locations at first and second times, acquire sets of terrain or structural information for first and second areas that respectively include the first and second estimated positions, use the acquired sets of information and the estimated positions to determine if the mobile device was near or within a structure at the first and second times, determine one or more values that are indicative of vertical movement by the mobile device during a period of time between the first time and the second time, compare the one or more values to one or more threshold conditions, and determine a context of the mobile device based on the comparison.

IPC Classes  ?

• G06F 3/01 - Input arrangements or combined input and output arrangements for interaction between user and computer
• H04M 1/72457 - User interfaces specially adapted for cordless or mobile telephones with means for adapting the functionality of the device according to specific conditions according to geographic location
• H04M 1/72403 - User interfaces specially adapted for cordless or mobile telephones with means for local support of applications that increase the functionality
• H04M 1/72454 - User interfaces specially adapted for cordless or mobile telephones with means for adapting the functionality of the device according to specific conditions according to context-related or environment-related conditions
• G01P 15/02 - Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces
• G06F 3/041 - Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• H04N 21/45 - Management operations performed by the client for facilitating the reception of or the interaction with the content or administrating data related to the end-user or to the client device itself, e.g. learning user preferences for recommending movies 
• H04W 4/021 - Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences

Abstract

Calibrating weather stations using maximum allowed altitude errors. Particular embodiments described herein include machines that determine a maximum allowed pressure calibration error for a weather station in a network of weather stations, determine a temperature variation associated with an environment in which the weather station resides, determine a maximum allowed altitude error for the weather station using the maximum allowed pressure calibration error and the temperature variation, and use the maximum allowed altitude error to determine if a first maximum possible altitude error associated with a first approach for estimating an altitude of the weather station exceeds the maximum allowed altitude error. If the first maximum possible altitude error associated with the first approach does not exceed the maximum allowed altitude error, the first approach is used to estimate an altitude of the weather station for use in calibrating a pressure sensor of the weather station.

IPC Classes  ?

• G01W 1/18 - Testing or calibrating meteorological apparatus
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

Calibrating an unstable sensor of a mobile device. Systems and methods for calibrating a sensor of a mobile device determine a first estimated position of the mobile device without using any measurement from the sensor of the mobile device, generate a second estimated position of the mobile device using a measurement from the sensor, estimate a sensor error of the sensor using the first estimated position and the second estimated position, and use the sensor error to determine a calibration value for adjusting one or more measurements from the sensor.

IPC Classes  ?

• G01C 17/38 - Testing, calibrating, or compensating of compasses
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 21/16 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
• G01S 19/14 - Receivers specially adapted for specific applications
• G01C 21/10 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01S 19/40 - Correcting position, velocity or attitude
• G01S 5/00 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations

Abstract

Determining one or more heights of one or more mobile devices above surfaces. Particular embodiments described herein include machines that retrieve first data (e.g., measurement value(s) determined by sensor(s) of a mobile device or estimated position(s) of the mobile device), determine a location context based on the first data, identify second data (e.g., measurement value(s) determined by sensor(s) of the mobile device or status indicator value(s) of feature(s) of the mobile device) to retrieve for use in determining an estimated height above a surface at which the mobile device is located based on the determined location context, retrieve the second data, and determine an estimated height above a surface at which the mobile device is located based on the retrieved second data.

IPC Classes  ?

• H04M 1/725 - Cordless telephones
• H04W 4/029 - Location-based management or tracking services
• H04W 4/16 - Communication-related supplementary services, e.g. call-transfer or call-hold
• H04M 1/72454 - User interfaces specially adapted for cordless or mobile telephones with means for adapting the functionality of the device according to specific conditions according to context-related or environment-related conditions

Abstract

Determining which reference-level pressures, from among a plurality of available reference-level pressures, are used when estimating an altitude of a mobile device. Different systems and methods determine isobars based on reference-level pressures of weather stations, and then use the isobars in different ways to identify particular reference-level pressures for use in estimated an altitude of a mobile device. One approach determines the smallest distance between an initial estimated position of a mobile device and a neighboring isobar, and then uses that distance to identify reference-level pressures. Another approach identifies reference-level pressures between an isobar on which an initial estimated position of a mobile device is location and a neighboring isobar. Yet another approach compares the number of identified reference-level pressures and/or locations of the identified reference-level pressures against threshold conditions before determining which reference-level pressures to use.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01W 1/16 - Measuring atmospheric potential differences, e.g. due to electrical charges in clouds
• G01L 7/00 - Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements

Abstract

Systems and methods are described for determining position of a receiver. The positioning system comprises a transmitter network including transmitters that broadcast positioning signals. The positioning system comprises a remote receiver that acquires and tracks the positioning signals and/or satellite signals. The satellite signals are signals of a satellite-based positioning system. A first mode of the remote receiver uses terminal-based positioning in which the remote receiver computes a position using the positioning signals and/or the satellite signals. The positioning system comprises a server coupled to the remote receiver. A second operating mode of the remote receiver comprises network-based positioning in which the server computes a position of the remote receiver from the positioning signals and/or satellite signals, where the remote receiver receives and transfers to the server the positioning signals and/or satellite signals.

IPC Classes  ?

• G01S 1/08 - Systems for determining direction or position line
• G01S 5/10 - Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements
• H04B 1/7087 - Carrier synchronisation aspects
• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• H04W 72/30 - Resource management for broadcast services
• H04W 72/51 - Allocation or scheduling criteria for wireless resources based on terminal or device properties
• G01S 19/46 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement the supplementary measurement being of a radio-wave signal type
• G01S 19/24 - Acquisition or tracking of signals transmitted by the system
• G01S 19/42 - Determining position
• H04B 7/26 - Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
• H04W 72/0446 - Resources in time domain, e.g. slots or frames
• H04B 1/709 - Correlator structure
• H04W 56/00 - Synchronisation arrangements

Abstract

A method involves determining, at a mobile device or a service, an uncertainty in height above a reference altitude, an estimated 2D position of the mobile device, and an uncertainty in terrain height above the reference altitude using the estimated 2D position. An uncertainty in height above terrain, of the mobile device, is determined at the mobile device or a server using the uncertainty in height above the reference altitude and the uncertainty in terrain height above the reference altitude.

IPC Classes  ?

• H04W 4/02 - Services making use of location information
• G01S 19/51 - Relative positioning
• G01C 5/00 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels

Abstract

Multiple calibration results for calibrating a barometric pressure sensor based on data received from a device containing the sensor are determined and stored in a table. The table is updated based on rules regarding a relationship between each calibration result and a current calibration value. The calibration results are weighted and combined to determine a combined calibration result. The calibration value for calibrating the sensor is selected from the calibration results, the combined calibration results, or the current calibration value based on a selection criteria.

IPC Classes  ?

• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

Determining when to calibrate a pressure sensor of a mobile device. Particular systems and methods determine values of a plurality of metrics, determine weights for the metric values, determine weighted metric values by applying the weights to the metric values, use the weighted metric values to determine if a pressure sensor of the mobile device should be calibrated using information associated with the first location, and calibrate the pressure sensor of the mobile device using the information associated with the first location if a determination is made that the pressure sensor of the mobile device should be calibrated using information associated with the first location.

IPC Classes  ?

• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• G01L 19/00 - MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE - Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
• G01C 21/20 - Instruments for performing navigational calculations

Abstract

Using a pressure sensor of a mobile device to improve the accuracy of determined contexts. Particular embodiments described herein include machines that determine a context of a mobile device, and determine if the determined context is accurate using multiple measurements of pressure from a pressure sensor of the mobile device.

IPC Classes  ?

• H04W 4/38 - Services specially adapted for particular environments, situations or purposes for collecting sensor information
• H04W 4/02 - Services making use of location information
• H04W 4/029 - Location-based management or tracking services
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management

Abstract

Embodiments describe determining position by selecting a set of digital pseudorandom sequences. The magnitudes of the cross-correlation between any two sequences of the chosen set are below a specified threshold. A subset of digital pseudorandom sequences are selected from the set such that the magnitudes of the autocorrelation function of each member of the subset, within a specified region adjacent to the peak of the autocorrelation function, are equal to or less than a prescribed value. Each transmitter transmits a positioning signal, and at least a portion of the positioning signal is modulated with at least one member of the subset. At least two transmitters of the plurality of transmitters modulate respective positioning signals with different members of the subset of digital pseudorandom sequences.

IPC Classes  ?

• G01S 19/45 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement
• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• H04B 1/709 - Correlator structure

Abstract

Determining calibration values for atmospheric sensors that provide measured pressures used for estimating altitudes of mobile devices. Particular systems and methods determine if any uncalibrated reference-level pressure estimates associated with an unstable pressure sensor should not be used when calibrating the unstable pressure sensor, and calibrate the unstable pressure sensor using all of the uncalibrated reference-level pressure estimates except any uncalibrated reference-level pressure estimate that should not be used when calibrating the unstable pressure sensor.

IPC Classes  ?

• G01C 5/00 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• H04W 4/029 - Location-based management or tracking services
• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure

Abstract

Methods and machines involve detecting when a mobile device is in a first area and a second area at different times, collecting pressure data from the mobile device and reference sensor(s) to estimate altitudes of the mobile device within the first area and the second area, collecting terrain altitudes associated with the first area and the second area, and using a difference between the estimated altitudes and a difference between the terrain altitudes to determine a height of a floor. The estimated floor height may be used to calibrate a pressure sensor of a mobile device.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• H04W 4/33 - Services specially adapted for particular environments, situations or purposes for indoor environments, e.g. buildings
• H04W 4/021 - Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences

Abstract

Determining contexts of mobile devices. Particular embodiments described herein include machines that determine two estimated positions of a mobile device that respectively correspond to first and second locations at first and second times, acquire sets of terrain or structural information for first and second areas that respectively include the first and second estimated positions, use the acquired sets of information and the estimated positions to determine if the mobile device was within a structure at the first and second times, determine one or more values that are indicative of vertical movement by the mobile device during a period of time between the first time and the second time, compare the one or more values to one or more threshold conditions, and determine a context of the mobile device based on the comparison.

IPC Classes  ?

• G06F 3/01 - Input arrangements or combined input and output arrangements for interaction between user and computer
• H04M 1/72457 - User interfaces specially adapted for cordless or mobile telephones with means for adapting the functionality of the device according to specific conditions according to geographic location
• H04M 1/72403 - User interfaces specially adapted for cordless or mobile telephones with means for local support of applications that increase the functionality
• H04M 1/72454 - User interfaces specially adapted for cordless or mobile telephones with means for adapting the functionality of the device according to specific conditions according to context-related or environment-related conditions
• G01P 15/02 - Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces
• G06F 3/041 - Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• H04N 21/45 - Management operations performed by the client for facilitating the reception of or the interaction with the content or administrating data related to the end-user or to the client device itself, e.g. learning user preferences for recommending movies 
• H04W 4/021 - Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences

Abstract

Determining, broadcasting and using reference pressure data in a network of transmitters. Particular embodiments described herein include machines that select atmospheric data from weather stations within a transmitter network, use the selected atmospheric data to determine a reference atmospheric value, and transmit the reference atmospheric value from a transmitter to a mobile device for use in estimating an altitude of the mobile device. The atmospheric data may include any of reference pressures form the weather stations, measured temperatures from the weather stations, or reference temperatures from the weather stations. The reference atmospheric value may include a reference pressure value of a reference altitude, or a reference temperature value.

IPC Classes  ?

• G01W 1/06 - Instruments for indicating weather conditions by measuring two or more variables, e.g. humidity, pressure, temperature, cloud cover or wind speed giving a combined indication of weather conditions
• G01W 1/10 - Devices for predicting weather conditions
• H04W 4/029 - Location-based management or tracking services
• G01S 5/00 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• H04H 60/71 - Systems specially adapted for using specific information, e.g. geographical or meteorological information using meteorological information
• H04W 4/02 - Services making use of location information

Abstract

Using a pressure sensor of a mobile device to improve the reliability of determined contexts. Particular embodiments described herein include machines that determine a context of a mobile device, and determine if the determined context is accurate using one or more measurements of pressure from a pressure sensor of the mobile device.

IPC Classes  ?

• H04W 4/38 - Services specially adapted for particular environments, situations or purposes for collecting sensor information
• H04W 4/029 - Location-based management or tracking services
• H04W 4/02 - Services making use of location information
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management

Abstract

Determining one or more heights of one or more mobile devices above surfaces. Particular embodiments described herein include machines that retrieve first data (e.g., measurement value(s) determined by sensor(s) of a mobile device or estimated position(s) of the mobile device), determine a location context based on the first data, identify second data (e.g., measurement value(s) determined by sensor(s) of the mobile device or status indicator value(s) of feature(s) of the mobile device) to retrieve for use in determining an estimated height above a surface at which the mobile device is located based on the determined location context, retrieve the second data, and determine an estimated height above a surface at which the mobile device is located based on the retrieved second data.

IPC Classes  ?

• H04M 1/725 - Cordless telephones
• H04M 1/72454 - User interfaces specially adapted for cordless or mobile telephones with means for adapting the functionality of the device according to specific conditions according to context-related or environment-related conditions
• H04W 4/029 - Location-based management or tracking services
• H04W 4/16 - Communication-related supplementary services, e.g. call-transfer or call-hold

Abstract

Determining if a receiver is inside or outside a building or area. Particular systems and methods for determining if a receiver is inside or outside a building determine an estimate of a position of a receiver, and use the estimate of the position of the receiver and other data to determine if the position of the receiver is inside a first building. The other data may include locations of geo-fences inside buildings, heights of buildings, or other types of data.

IPC Classes  ?

• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• H04B 7/0413 - MIMO systems
• H04B 7/0452 - Multi-user MIMO systems
• H04B 7/06 - Diversity systems; Multi-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
• H04W 52/02 - Power saving arrangements
• H04W 4/029 - Location-based management or tracking services
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• H04W 4/021 - Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences

Abstract

Determining one or more heights of one or more mobile devices above surfaces. Particular embodiments described herein include machines that retrieve first data (e.g., measurement value(s) determined by sensor(s) of a mobile device or estimated position(s) of the mobile device), determine a location context based on the first data, identify second data (e.g., measurement value(s) determined by sensor(s) of the mobile device or status indicator value(s) of feature(s) of the mobile device) to retrieve for use in determining an estimated height above a surface at which the mobile device is located based on the determined location context, retrieve the second data, and determine an estimated height above a surface at which the mobile device is located based on the retrieved second data.

IPC Classes  ?

• H04M 1/725 - Cordless telephones
• H04W 4/029 - Location-based management or tracking services
• H04W 4/16 - Communication-related supplementary services, e.g. call-transfer or call-hold

Abstract

Systems and methods are described for determining position of a receiver. The positioning system comprises a transmitter network including transmitters that broadcast positioning signals. The positioning system comprises a remote receiver that acquires and tracks the positioning signals and/or satellite signals. The satellite signals are signals of a satellite-based positioning system. A first mode of the remote receiver uses terminal-based positioning in which the remote receiver computes a position using the positioning signals and/or the satellite signals. The positioning system comprises a server coupled to the remote receiver. A second operating mode of the remote receiver comprises network-based positioning in which the server computes a position of the remote receiver from the positioning signals and/or satellite signals, where the remote receiver receives and transfers to the server the positioning signals and/or satellite signals.

IPC Classes  ?

• H04B 1/7087 - Carrier synchronisation aspects
• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• G01S 19/46 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement the supplementary measurement being of a radio-wave signal type
• G01S 5/10 - Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements
• G01S 1/08 - Systems for determining direction or position line
• G01S 19/24 - Acquisition or tracking of signals transmitted by the system
• G01S 19/42 - Determining position
• H04B 7/26 - Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
• H04W 72/00 - Local resource management
• H04W 72/04 - Wireless resource allocation
• H04B 1/709 - Correlator structure
• H04W 56/00 - Synchronisation arrangements

Abstract

Pressure-based estimation of a mobile device altitude or calibration of a pressure sensor involves machines that determine if a reference-level pressure value based on one or more measurements of pressure from a network of weather stations should or should not be used to calibrate a pressure sensor of a mobile device or to estimate an altitude of the mobile device. If reference-level pressure value should be used, the reference-level pressure value is used to calibrate a pressure sensor of a mobile device or to estimate an altitude of the mobile device. If the reference-level pressure value should not be used, a trend in pressure is determined, an estimated reference-level pressure value based on the trend is determined, and the estimated reference-level pressure value is used to calibrate a pressure sensor of a mobile device or to estimate an altitude of the mobile device.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure

Abstract

Embodiments describe determining position by selecting a set of digital pseudorandom sequences. The magnitudes of the cross-correlation between any two sequences of the chosen set are below a specified threshold. A subset of digital pseudorandom sequences are selected from the set such that the magnitudes of the autocorrelation function of each member of the subset, within a specified region adjacent to the peak of the autocorrelation function, are equal to or less than a prescribed value. Each transmitter transmits a positioning signal, and at least a portion of the positioning signal is modulated with at least one member of the subset. At least two transmitters of the plurality of transmitters modulate respective positioning signals with different members of the subset of digital pseudorandom sequences.

IPC Classes  ?

• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• G01S 19/45 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• G01S 19/48 - Determining position by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• H04B 1/709 - Correlator structure

Abstract

Calibrating an unstable sensor of a mobile device. Systems and methods for calibrating a sensor of a mobile device determine a first estimated position of the mobile device without using any measurement from the sensor of the mobile device, generate a second estimated position of the mobile device using a measurement from the sensor, estimate a sensor error of the sensor using the first estimated position and the second estimated position, and use the sensor error to determine a calibration value for adjusting one or more measurements from the sensor.

IPC Classes  ?

• G01C 17/38 - Testing, calibrating, or compensating of compasses
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01C 21/16 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
• G01S 19/14 - Receivers specially adapted for specific applications
• G01C 21/10 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration
• G01S 19/40 - Correcting position, velocity or attitude

Abstract

Extending the spatial coverage of a reference pressure network. Particular embodiments described herein include machines that initially determine that an estimated position of a mobile device resides outside a coverage area of a network of reference pressure sensors. Reference-level pressures corresponding to reference pressure sensors of the network are determined using measurements of pressure from the network of reference pressure sensors. A pressure pattern for a region that includes the estimated position and an area not included in the coverage area of the network is determined using reference-level pressures that were not determined using measurements of pressure from the network of reference pressure sensors. The reference-level pressures corresponding to reference pressure sensors of the network and the pressure pattern are used to determine a reference-level pressure value for use in calibrating a pressure sensor of the mobile device or for use in estimating an altitude of the mobile device.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 21/20 - Instruments for performing navigational calculations

Abstract

Estimating a difference in height between two floors in a building for use in estimating a height or an altitude of one of the two floors. Particular embodiments estimate a height difference between a first floor and a second floor based on a first outdoor temperature of a first time period, a second outdoor temperature of a second time period, a third temperature that is based on an indoor temperature of the first time period or the second time period, a first estimated difference in height between the first and second floors that is based on measurements of pressure from mobile devices when those mobile devices were on the first and second floors during the first time period, and a second estimated difference in height between the first and second floors that is based on measurements of pressure from mobile devices when those mobile devices were on the first and second floors during the second time period.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 21/20 - Instruments for performing navigational calculations
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management

Abstract

Determining an indoor or outdoor location of a mobile device. Particular embodiments described herein determine a geographic area of potential locations in which a mobile device resides, identify any buildings that occupy part of the geographic area, and determine if the mobile device does not reside inside any building, the mobile device resides inside a particular building from the identified buildings, or that one or more of the identified buildings are candidate buildings in which the mobile device may reside based on the geographic area and building footprints of the identified buildings.

IPC Classes  ?

• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• G01W 1/02 - Instruments for indicating weather conditions by measuring two or more variables, e.g. humidity, pressure, temperature, cloud cover or wind speed
• H04W 4/33 - Services specially adapted for particular environments, situations or purposes for indoor environments, e.g. buildings
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves

Abstract

Determining which reference-level pressures, from among a plurality of available reference-level pressures, are used when estimating an altitude of a mobile device. Different systems and methods determine isobars based on reference-level pressures of weather stations, and then use the isobars in different ways to identify particular reference-level pressures for use in estimated an altitude of a mobile device. One approach determines the smallest distance between an initial estimated position of a mobile device and a neighboring isobar, and then uses that distance to identify reference-level pressures. Another approach identifies reference-level pressures between an isobar on which an initial estimated position of a mobile device is location and a neighboring isobar. Yet another approach compares the number of identified reference-level pressures and/or locations of the identified reference-level pressures against threshold conditions before determining which reference-level pressures to use.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01W 1/16 - Measuring atmospheric potential differences, e.g. due to electrical charges in clouds
• G01L 7/00 - Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements

Abstract

Determining calibration values for atmospheric sensors that provide measured pressures used for estimating altitudes of mobile devices. Particular systems and methods determine if any uncalibrated reference-level pressure estimates associated with an unstable pressure sensor should not be used when calibrating the unstable pressure sensor, and calibrate the unstable pressure sensor using all of the uncalibrated reference-level pressure estimates except any uncalibrated reference-level pressure estimate that should not be used when calibrating the unstable pressure sensor.

IPC Classes  ?

• G01C 5/00 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• H04W 4/029 - Location-based management or tracking services
• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure

Abstract

Determining where to place atmospheric sensors that provide measurements of pressure used to estimate an altitude of a mobile device in an environment. Generally, systems and methods determine where atmospheric sensors can be placed relative to each other in order to achieve a required level of accuracy when an altitude of a mobile device is estimated using pressure measurements from the atmospheric sensors in the network. Particular systems and methods determine a maximum distance for separating adjacent atmospheric sensors, or otherwise determine where to place atmospheric sensors relative to each other based on expected pressure distribution of an environment.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 5/00 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
• G01C 21/20 - Instruments for performing navigational calculations

Abstract

Determining when to calibrate a pressure sensor of a mobile device. Particular systems and methods determine values of a plurality of metrics based on how data collected at a first location of a mobile device relates to threshold conditions, determine weights for the metric values, determine weighted metric values by applying the weights to the metric values, use the weighted metric values to determine if a pressure sensor of the mobile device should be calibrated using information associated with the first location, and calibrate the pressure sensor of the mobile device using the information associated with the first location if a determination is made that the pressure sensor of the mobile device should be calibrated using information associated with the first location.

IPC Classes  ?

• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• G01L 19/00 - MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE - Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
• G01C 21/20 - Instruments for performing navigational calculations

Abstract

Determining when an estimated altitude of a mobile device can be used for calibration or location determination. Particular systems and methods determine an area in which the mobile device is expected to reside, determine an altitude value of each section of a plurality of sections in the area, determine if the altitude values meet a threshold condition, and determine that the estimated altitude of the mobile device can be used for determining the position of the mobile device or for calibrating a pressure sensor of the mobile device when the altitude values meet the threshold condition.

IPC Classes  ?

• G01C 5/00 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels
• G06F 17/18 - Complex mathematical operations for evaluating statistical data
• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• H04W 4/029 - Location-based management or tracking services
• G01S 5/00 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations

Abstract

Determining whether a mobile device is inside an environment experiencing adverse pressure variation conditions. Particular systems and methods for determining whether a mobile device is inside an environment experiencing adverse pressure variation conditions detect a change in pressure measured by a mobile device that is caused by an HVAC effect of a building or a vehicle, determine a likelihood that the mobile device is inside a building based on an estimated position of the mobile device relative to the building, and determine that the mobile device is inside the building or inside a vehicle based on the likelihood that the mobile device is inside the building.

IPC Classes  ?

• H04W 24/00 - Supervisory, monitoring or testing arrangements
• H04W 4/029 - Location-based management or tracking services
• G01L 19/00 - MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE - Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure
• H04W 4/33 - Services specially adapted for particular environments, situations or purposes for indoor environments, e.g. buildings
• G01C 21/20 - Instruments for performing navigational calculations
• H04W 4/021 - Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences

Abstract

Using atmospheric data from one or more reference nodes to estimate an altitude of a receiver. Assistance data associated with a set of reference nodes within a region is identified, and the assistance data is used to identify atmospheric reference data associated with a subset of selected reference nodes. An estimate of the receiver's altitude is generated using the atmospheric reference data from the subset of reference nodes.

IPC Classes  ?

• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01S 19/45 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement

Abstract

Improving an estimated altitude of a receiver by mitigating the effects of transmitter heating. Systems and methods for improving estimates of a receiver's altitude determine a reference pressure at a reference altitude using a temperature measured at a transmitter or another temperature value, an altitude of the transmitter, and a pressure measured by the transmitter or another pressure value. A local reference pressure for a receiver is determined using the reference pressure and other reference pressures from other transmitters. Reference pressures from overheating transmitters may be weighted less than reference pressures from other transmitters when determining the local reference pressure. The local reference pressure is then used to estimate the altitude of the receiver.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management

Abstract

Reducing power consumption of a receiver in association with estimating the receiver's position using ranging signals. Systems and methods may determine power reduction strategy information, identify a power reduction strategy using the determined power reduction strategy information, and place one or more modules of the receiver into a reduced power state using the identified power reduction strategy. The power reduction strategy may result in powering off different circuitry of the receiver at different times, and under different circumstances.

IPC Classes  ?

• H04W 52/02 - Power saving arrangements
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01S 5/10 - Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements
• H04B 17/373 - Predicting channel quality parameters
• H04B 7/26 - Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
• H04B 17/318 - Received signal strength

Abstract

Determining when a barometric-based approach for estimating an unknown altitude of a mobile device should not be used. Different approaches determine if estimating an unknown altitude of a mobile device using a measured atmospheric condition will result in an estimated altitude having acceptable or unacceptable error. If use of the measured atmospheric condition would result in acceptable error, the measured atmospheric condition is used to estimate the unknown altitude. If use of the measured atmospheric condition would result in unacceptable error, the measured atmospheric condition is not used to estimate the unknown altitude. The resultant altitude estimate is then used to locate the mobile device.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01N 33/00 - Investigating or analysing materials by specific methods not covered by groups

Abstract

A position location system comprises transmitters that broadcast positioning signals. Each broadcasted positioning signal comprises a pseudorandom ranging signal. The position location system includes a remote receiver that acquires and measures the time of arrival of the positioning signals received at the remote receiver. During an interval of time, at least two positioning signals are transmitted concurrently by the transmitters and received concurrently at the remote receiver. The two positioning signals have carrier frequencies offset from one another by an offset that is less than approximately twenty-five percent of the bandwidth of each positioning signal of the two positioning signals. Cross-interference between the positioning signals is reduced by tuning the remote receiver to a frequency of a selected signal of the two positioning signals and correlating the selected signal with a reference pseudorandom ranging signal matched to a transmitted pseudorandom ranging signal of the selected signal.

IPC Classes  ?

• G01S 19/21 - Interference related issues
• G01S 19/48 - Determining position by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• G01S 19/45 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement
• G01S 19/07 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing data for correcting measured positioning data, e.g. DGPS [differential GPS] or ionosphere corrections
• G01S 19/05 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing aiding data
• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters

Abstract

Identifying and estimating values of atmospheric conditions for use in estimating an altitude of a mobile device. Systems and methods for monitoring one or more conditions before estimating an altitude of a mobile device may receive a reference pressure that was computed using a measurement of pressure from a first reference pressure sensor at a first location, wherein the received reference pressure specifies an estimated pressure for a reference altitude, and determine if a threshold change in measured pressure by the first reference pressure sensor is detected. If the threshold change in measured pressure is detected, the systems and methods may compute a calibration value for the first reference pressure sensor, or if the threshold change in measured pressure is not detected, the systems and methods may identify a previously-determined calibration value. The systems and methods may then compute an adjusted reference pressure using the received reference pressure and either the computed calibration value or the previously-determined calibration value, and compute an estimate of the altitude of the mobile device using the adjusted reference pressure and a measurement of pressure from the mobile device.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01K 7/00 - Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat
• G01L 7/00 - Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements

Abstract

Identifying and estimating values of atmospheric conditions for use in estimating an altitude of a mobile device. Systems and methods for monitoring one or more conditions before estimating an altitude of a mobile device may receive a reference pressure that was determined using a measurement of pressure measured by a reference pressure sensor, and determine if a temperature condition is detected. After determining that the temperature condition is not detected, the systems and methods may compute a first estimate of an altitude of a mobile device using the reference pressure. After determining that the temperature condition is detected, the systems and methods may compute an estimate of a pressure at the location of the reference pressure sensor using the reference pressure, a first measurement of temperature that was used to compute the reference pressure, an estimated altitude of the location of the reference pressure sensor, and the reference altitude, and then compute a second estimate of the altitude of the mobile device using the estimate of pressure and a second measurement of temperature that was measured at another location that is different from the location of the reference pressure sensor.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01K 7/00 - Measuring temperature based on the use of electric or magnetic elements directly sensitive to heat
• G01L 7/00 - Measuring the steady or quasi-steady pressure of a fluid or a fluent solid material by mechanical or fluid pressure-sensitive elements

Abstract

Determining if a receiver is inside or outside a building or area. Particular systems and methods for determining if a receiver is inside or outside a building determine an estimate of a position of a receiver, and use the estimate of the position of the receiver and other data to determine if the position of the receiver is inside a first building. The other data may include locations of geo-fences inside buildings, heights of buildings, or other types of data.

IPC Classes  ?

• H04W 16/24 - Cell structures
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• H04W 4/021 - Services related to particular areas, e.g. point of interest [POI] services, venue services or geofences
• H04W 52/02 - Power saving arrangements
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• H04W 4/029 - Location-based management or tracking services
• H04B 7/06 - Diversity systems; Multi-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
• H04B 7/0452 - Multi-user MIMO systems
• H04B 7/0413 - MIMO systems
• H04B 7/10 - Polarisation diversity; Directional diversity
• H04W 16/22 - Traffic simulation tools or models
• H04B 7/22 - Scatter propagation systems
• H04W 16/18 - Network planning tools
• H04B 7/12 - Frequency diversity
• H04W 16/14 - Spectrum sharing arrangements
• H04W 16/32 - Hierarchical cell structures
• H04W 40/00 - Communication routing or communication path finding
• H04W 36/00 - Handoff or reselecting arrangements
• H04L 5/00 - Arrangements affording multiple use of the transmission path
• H01Q 1/24 - Supports; Mounting means by structural association with other equipment or articles with receiving set
• H04L 1/06 - Arrangements for detecting or preventing errors in the information received by diversity reception using space diversity

Abstract

Estimating a position of a mobile device. Particular systems and methods for estimating a position of a mobile device using information from two positioning technologies determine different position estimates for the mobile device using different positioning technologies, and determine a final position estimate for the mobile device using a weighted combination of the different position estimates. In some implementations, the weighted combination is a weighted average or a weighted median of the different position estimates. Weights may be determined using respective uncertainty metrics corresponding to the respective position estimates.

IPC Classes  ?

• H04W 4/02 - Services making use of location information
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01S 19/31 - Acquisition or tracking of other signals for positioning
• G01S 19/24 - Acquisition or tracking of signals transmitted by the system
• G01S 5/14 - Determining absolute distances from a plurality of spaced points of known location
• G01S 19/48 - Determining position by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• G06F 17/18 - Complex mathematical operations for evaluating statistical data
• G01S 19/20 - Integrity monitoring, fault detection or fault isolation of space segment

Abstract

A receiver capable of receiving and a transmitter capable of transmitting LTE (Long-Term Evolution) signals. The receiver is capable of executing firmware to determine position location from a received LTE-like position waveform over signals modulated on a carrier in a positioning frequency band. In one embodiment the positioning signals are transmitted in a positioning band continuously for up to 100 ms, allowing the receiver to integrate the received positioning signals over a period of up to 100 ms. In one such embodiment, the signals can be integrated coherently for up to 60 ms, assuming acceptable stability of the clock in the receiver and further assuming that less than a predetermined amount of Doppler shift has been introduced in the received signal. The number of physical resource blocks (PRB) can be determined to optimize the signal allocation for the available bandwidth.

IPC Classes  ?

• H04W 72/04 - Wireless resource allocation
• H04W 4/02 - Services making use of location information
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• H04L 5/00 - Arrangements affording multiple use of the transmission path
• H04W 88/02 - Terminal devices
• H04W 84/04 - Large scale networks; Deep hierarchical networks
• H04L 27/26 - Systems using multi-frequency codes

Abstract

Positioning systems and methods for estimating an altitude of a receiver. In some embodiments, pressure and temperature information from a network of sensors is received by the receiver, and the pressure and temperature information from the network of sensors is used along with pressure information measured at a position of the receiver to estimate the altitude of the receiver.

IPC Classes  ?

• G01S 19/06 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing aiding data employing an initial estimate of the location of the receiver as aiding data or in generating aiding data
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01S 5/14 - Determining absolute distances from a plurality of spaced points of known location
• G01S 19/10 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals
• G01S 19/46 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement the supplementary measurement being of a radio-wave signal type
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means

Abstract

Embodiments describe determining position by selecting a set of digital pseudorandom sequences. The magnitudes of the cross-correlation between any two sequences of the chosen set are below a specified threshold. A subset of digital pseudorandom sequences are selected from the set such that the magnitudes of the autocorrelation function of each member of the subset, within a specified region adjacent to the peak of the autocorrelation function, are equal to or less than a prescribed value. Each transmitter transmits a positioning signal, and at least a portion of the positioning signal is modulated with at least one member of the subset. At least two transmitters of the plurality of transmitters modulate respective positioning signals with different members of the subset of digital pseudorandom sequences.

IPC Classes  ?

• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• G01S 19/45 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement
• G01S 19/48 - Determining position by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system
• H04B 1/709 - Correlator structure

Abstract

Devices, systems, and methods for sending positional information from transmitters/beacons. In one implementation a transmitter generates a range block including a ranging signal and a hybrid block including positioning data, and sends the range block and hybrid block at different times. A user device may receive signals from a plurality of transmitters and generates position/location information using trilateration and measured altitude information in comparison with transmitter altitude information.

IPC Classes  ?

• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• G01S 1/04 - Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmitters; Receivers co-operating therewith using radio waves - Details
• G01S 19/46 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement the supplementary measurement being of a radio-wave signal type
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management

Abstract

Calibrating an unstable sensor of a mobile device. Systems and methods for calibrating a sensor of a mobile device determine a first estimated position of the mobile device without using any measurement from the sensor of the mobile device, generate a second estimated position of the mobile device using a measurement from the sensor, estimate a sensor error of the sensor using the first estimated position and the second estimated position, and use the sensor error to determine a calibration value for adjusting one or more measurements from the sensor.

IPC Classes  ?

• G01C 17/38 - Testing, calibrating, or compensating of compasses
• G01C 21/10 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration
• G01C 25/00 - Manufacturing, calibrating, cleaning, or repairing instruments or devices referred to in the other groups of this subclass
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01C 21/16 - Navigation; Navigational instruments not provided for in groups by using measurement of speed or acceleration executed aboard the object being navigated; Dead reckoning by integrating acceleration or speed, i.e. inertial navigation
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01S 19/14 - Receivers specially adapted for specific applications
• G01S 19/40 - Correcting position, velocity or attitude

Abstract

Systems and methods for improving correlation. In at least one system and method, a signal is received and divided into a plurality of slices. Each of the slices is divided into a plurality of sub-slices. A plurality of chips of a PN code are generated, and sub-slice correlation results are generated in parallel. Summation of the sub-slice correlation results generates a slice correlation results, and the accumulated slice correlation results provide a correlation result.

IPC Classes  ?

• H04B 1/00 - TRANSMISSION - Details of transmission systems not characterised by the medium used for transmission
• G06F 7/52 - Multiplying; Dividing
• H04B 1/7075 - Synchronisation aspects with code phase acquisition

Abstract

Systems and methods are described for determining position of a receiver. The positioning system comprises a transmitter network including transmitters that broadcast positioning signals. The positioning system comprises a remote receiver that acquires and tracks the positioning signals and/or satellite signals. The satellite signals are signals of a satellite-based positioning system. A first mode of the remote receiver uses terminal-based positioning in which the remote receiver computes a position using the positioning signals and/or the satellite signals. The positioning system comprises a server coupled to the remote receiver. A second operating mode of the remote receiver comprises network-based positioning in which the server computes a position of the remote receiver from the positioning signals and/or satellite signals, where the remote receiver receives and transfers to the server the positioning signals and/or satellite signals.

IPC Classes  ?

• H04B 1/7087 - Carrier synchronisation aspects
• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• G01S 19/46 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement the supplementary measurement being of a radio-wave signal type
• G01S 5/10 - Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements
• G01S 1/08 - Systems for determining direction or position line
• G01S 19/24 - Acquisition or tracking of signals transmitted by the system
• G01S 19/42 - Determining position
• H04B 7/26 - Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
• H04W 72/00 - Local resource management
• H04W 72/04 - Wireless resource allocation
• H04B 1/709 - Correlator structure
• H04W 56/00 - Synchronisation arrangements

Abstract

Reducing power consumption of a receiver in association with estimating the receiver's position using ranging signals. Systems and methods may determine power reduction strategy information, identify a power reduction strategy using the determined power reduction strategy information, and place one or more modules of the receiver into a reduced power state using the identified power reduction strategy. The power reduction strategy may result in powering off different circuitry of the receiver at different times, and under different circumstances.

IPC Classes  ?

• H04W 52/02 - Power saving arrangements
• H04B 17/373 - Predicting channel quality parameters
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01S 5/10 - Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements
• H04B 7/26 - Radio transmission systems, i.e. using radiation field for communication between two or more posts at least one of which is mobile
• H04B 17/318 - Received signal strength

Abstract

An interference removal filter that includes a combination of a first filter and a second filter, where the first filter passes signals over a frequency range of size B with a variation of less than +/−3 dB, where the peak value of the impulse response of the second filter is displaced in time from the peak value of the impulse response of the first filter by at least 2/B time units, and where the combination of the first filter and the second filter produces a notch in frequency at a frequency location within the frequency range.

IPC Classes  ?

• H04B 1/10 - Means associated with receiver for limiting or suppressing noise or interference
• G01S 7/02 - RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES - Details of systems according to groups , , of systems according to group
• G01S 19/21 - Interference related issues
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• H04K 3/00 - Jamming of communication; Counter-measures
• H04B 1/71 - Interference-related aspects the interference being narrowband interference
• H04B 1/7107 - Subtractive interference cancellation
• H03H 17/02 - Frequency-selective networks

Abstract

Determining an altitude error value associated with an estimated altitude of a mobile device. In certain disclosed systems and methods for determining an altitude error value associated with an estimated altitude of a mobile device, a first error value related to systematic error and a second error value related to statistical error are determined, and the altitude error value is determined using the first error value and the second error value.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• H04W 4/02 - Services making use of location information

Abstract

Interference detection and mitigation using maximal ratio combining in the correlation domain. Systems and methods for interference detection and mitigation using maximal ratio combining in the correlation domain may receive a plurality of copies of a positioning signal, compute a plurality of correlation functions using the received positioning signals; weight the plurality of correlation functions using a plurality of weights that are proportional to the quality of the plurality of correlation functions, and generate a combined correlation function by combining the weighted correlation functions.

IPC Classes  ?

• H04B 1/7115 - Constructive combining of multi-path signals, i.e. RAKE receivers
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• H04B 17/336 - Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• H04L 5/00 - Arrangements affording multiple use of the transmission path
• H04L 25/08 - Modifications for reducing interference; Modifications for reducing effects due to line faults

Abstract

Detecting and mitigating the effects of interference in a positioning system. A received signal is divided into a plurality of receive signal time/frequency (RSTF) values. A plurality of threshold values are determined based on expected energy values for the received signal. In one implementation, if a predetermined number of the RSTF values are above the threshold, the received signal is determined to be corrupt.

IPC Classes  ?

• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• H04B 17/336 - Signal-to-interference ratio [SIR] or carrier-to-interference ratio [CIR]
• H04L 5/00 - Arrangements affording multiple use of the transmission path
• H04L 25/08 - Modifications for reducing interference; Modifications for reducing effects due to line faults
• H04W 52/24 - TPC being performed according to specific parameters using SIR [Signal to Interference Ratio] or other wireless path parameters
• H04W 52/28 - TPC being performed according to specific parameters using user profile, e.g. mobile speed, priority or network state, e.g. standby, idle or non-transmission
• H04B 17/318 - Received signal strength
• H04B 17/345 - Interference values

Abstract

Synchronizing the local time of beacons. Systems and methods discipline a high-stability local clock of a designated beacon within a geographic region to a network time, and synchronize a local clock of another beacon within the geographic region to the network time.

IPC Classes  ?

• H04W 56/00 - Synchronisation arrangements
• H04W 40/24 - Connectivity information management, e.g. connectivity discovery or connectivity update
• H04B 7/185 - Space-based or airborne stations

Abstract

Determining building weather profile parameters, and correcting an estimated altitude of a receiver using the building weather profile parameters. Systems and methods for estimating an altitude of a receiver using building weather profile parameters may identify one or more weather profile parameters for a building, determine an initial estimate of a receiver's altitude at a floor inside the building, and use the initial estimate and the identified weather profile parameters to determine a corrected estimate of the receiver's altitude at the floor.

IPC Classes  ?

• H04W 4/04 - in a dedicated environment, e.g. buildings or vehicles
• G01W 1/06 - Instruments for indicating weather conditions by measuring two or more variables, e.g. humidity, pressure, temperature, cloud cover or wind speed giving a combined indication of weather conditions
• G01C 5/00 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels

Abstract

Estimating range bias in a timing-based radio positioning network. Systems and methods estimate range bias, and use the estimated bias to adjust an estimated range measurement for use in estimating a position of a receiver. Estimated range bias may be based on surveyed range errors associated with locations near the position of the receiver, or may alternatively be based on comparisons of different range measurements.

IPC Classes  ?

• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01S 5/14 - Determining absolute distances from a plurality of spaced points of known location

Abstract

Systems and methods for improving performance in terrestrial and satellite positioning systems. Signal processing systems and methods are described for selecting, from among a set of codes, certain codes having desired autocorrelation and/or cross-correlation properties. Systems and methods for generating, encoding, transmitting, and receiving signals using the selected codes are also described.

IPC Classes  ?

• H04B 1/00 - TRANSMISSION - Details of transmission systems not characterised by the medium used for transmission
• H04B 1/709 - Correlator structure
• G01S 19/46 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement the supplementary measurement being of a radio-wave signal type
• G01S 19/10 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals
• H04B 1/711 - Interference-related aspects the interference being multi-path interference
• H04W 4/02 - Services making use of location information

Abstract

Improving an estimated altitude of a receiver by mitigating the effects of transmitter heating. Systems and methods for improving estimates of a receiver's altitude determine a reference pressure at a reference altitude using a temperature measured at a transmitter or another temperature value, an altitude of the transmitter, and a pressure measured by the transmitter or another pressure value. A local reference pressure for a receiver is determined using the reference pressure and other reference pressures from other transmitters. Reference pressures from overheating transmitters may be weighted less than reference pressures from other transmitters when determining the local reference pressure. The local reference pressure is then used to estimate the altitude of the receiver.

IPC Classes  ?

• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management

Abstract

Transmitting information used to estimate a position of a mobile device. This disclosure describes NEAD-based and external location server (ELS)-based positioning systems and methods that determine when an identifier of a mobile device is not known or when the identifier of the mobile device is known but cannot be detected during a search by reference points, and to then provide a location of a reference point that had previous contact with the mobile device instead of an estimated position of the mobile device. The provided location of the reference point can be used by a location server to generate an estimate of mobile device position.

IPC Classes  ?

• H04W 24/00 - Supervisory, monitoring or testing arrangements
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• H04W 4/04 - in a dedicated environment, e.g. buildings or vehicles
• H04W 4/22 - Emergency connection handling

Abstract

Generating signals from non-GNSS transmitters, and processing the signals using a GNSS positioning module. Systems and methods identify a chipping rate, identify a PN code length, generate a PN code that has a length equal to the identified PN code length, generate a positioning signal using the identified chipping rate and the generated PN code, and transmit the positioning signal from the transmitter. The PN code length may produce, at the identified chipping rate, a PN code duration that is equal to or is a multiple of a PN code duration used in a GNSS system, the identified chipping rate may be equal to or a multiple of a chipping rate used in a GNSS system, and the identified PN code length may be equal to or a multiple of a PN code length used in a GNSS system.

IPC Classes  ?

• G01S 19/11 - Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers providing dedicated supplementary positioning signals wherein the cooperating elements are pseudolites or satellite radio beacon positioning system signal repeaters
• H04J 13/00 - Code division multiplex systems
• H04J 13/14 - Generation of codes with a zero correlation zone
• G01S 19/25 - Acquisition or tracking of signals transmitted by the system involving aiding data received from a cooperating element, e.g. assisted GPS

Abstract

Using estimates of a receiver's altitude to determine where a receiver is located and to refine a positioning system's estimate of a receiver's position. Systems and methods determine whether a receiver is inside or outside a building, and may use the determination to confirm or adjust an initial estimate of the receiver's position. Various approaches for making the determination and for assessing the initial estimate of the receiver's position are described.

IPC Classes  ?

• H04W 4/02 - Services making use of location information
• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• H04W 4/04 - in a dedicated environment, e.g. buildings or vehicles
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01S 19/42 - Determining position

Abstract

Estimating one or more positions of a receiver using one or more anchor points. Systems and methods for estimating a position of a receiver using a particular anchor point may identify an area of interest that includes anchor points, identify the particular anchor point, and then use information about the particular anchor point to estimate the position of the receiver.

IPC Classes  ?

• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• H04W 64/00 - Locating users or terminals for network management purposes, e.g. mobility management
• G01C 21/20 - Instruments for performing navigational calculations
• G01S 11/02 - Systems for determining distance or velocity not using reflection or reradiation using radio waves
• G01S 1/68 - Marker, boundary, call-sign, or like beacons transmitting signals not carrying directional information

Abstract

Using a calibration sensor to calibrate an unstable sensor from a network of unstable sensors. Approaches for using a calibration sensor to calibrate the unstable sensor initially identify an unstable sensor in a geographic region to be calibrated by a calibration sensor using a model of environmental conditions for the geographic region, and then use the model to determine how to calibrate the unstable sensor using the calibration sensor.

IPC Classes  ?

• G01L 27/02 - Testing or calibrating of apparatus for measuring fluid pressure of indicators
• G01L 27/00 - Testing or calibrating of apparatus for measuring fluid pressure

Abstract

Estimating the position of a receiver using positioning signals and Doppler frequency measurements. Approaches for estimating the position of a receiver using positioning signals and Doppler frequency shift measurements determine an initial estimate of a receiver's position using ranging signals from a first system, generate Doppler frequency shift measurements using the Doppler positioning signals from a second system, and refine the initial estimate using the Doppler frequency shift measurements.

IPC Classes  ?

• H04W 4/02 - Services making use of location information
• G01S 19/48 - Determining position by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system

Abstract

Using atmospheric data from one or more reference nodes to estimate an altitude of a receiver. Assistance data associated with a set of reference nodes within a region is identified, and the assistance data is used to identify atmospheric reference data associated with a subset of selected reference nodes. An estimate of the receiver's altitude is generated using the atmospheric reference data from the subset of reference nodes.

IPC Classes  ?

• G01S 5/02 - Position-fixing by co-ordinating two or more direction or position-line determinations; Position-fixing by co-ordinating two or more distance determinations using radio waves
• G01C 5/06 - Measuring height; Measuring distances transverse to line of sight; Levelling between separated points; Surveyors' levels by using barometric means
• G01S 19/45 - Determining position by combining measurements of signals from the satellite radio beacon positioning system with a supplementary measurement