Abstract: A method for estimating the pressure measurement bias of a barometric sensor in a wireless terminal. A location engine using the method generates an enhanced estimate of the measurement bias. The location engine generates the enhanced estimate based in part on Global Navigation Satellite System (GNSS)-based estimates of the elevation of the wireless terminal, which the terminal generates as it concurrently makes barometric pressure measurements. Each GNSS-based estimate of elevation is often generated from noisy measurements and has an associated uncertainty. The location engine accounts for the uncertainty in the GNSS estimates of elevation by applying an optimal estimation technique, such as Kalman filtering, on the biased pressure measurements and the GNSS-based estimates.

Abstract: A wireless telecommunication system is described that denies wireless telecommunication service to a wireless terminal in a proscribed area (e.g., prison, military installation, academic testing center, school, etc.). The system comprises an adjunct called a “service sentry.” The service sentry uses measurements of the location-dependent traits of the radio signals transmitted to, and received from, each wireless terminal in its purview to generate an estimate of the location of the wireless terminal. When the service sentry estimates that the wireless terminal has entered the proscribed area, it requests that the wireless switching center that services the proscribed area deny service to the wireless terminal. When the service sentry estimates that the wireless terminal has exited the proscribed area, it requests that the wireless switching center that services the proscribed area provide service to the wireless terminal.

Abstract: A wireless telecommunication system is described that denies wireless telecommunication service to a wireless terminal in a proscribed area (e.g., prison, military installation, academic testing center, school, etc.). The system comprises an adjunct called a “service sentry.” The service sentry uses measurements of the location-dependent traits of the radio signals transmitted to, and received from, each wireless terminal in its purview to generate an estimate of the location of the wireless terminal. When the service sentry estimates that the wireless terminal has entered the proscribed area, it requests that the wireless switching center that services the proscribed area deny service to the wireless terminal. When the service sentry estimates that the wireless terminal has exited the proscribed area, it requests that the wireless switching center that services the proscribed area provide service to the wireless terminal.

Abstract: A location engine uses the empirical measurements made by a scouting wireless terminal (i) to discover the existence of a reference radio within a geographic region; (ii) to generate an estimate of the location of the newly-discovered reference radio, and (iii) to generate an estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio. The location engine then uses: (i) the estimate of the location of the newly-discovered reference radio, and (ii) the estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio, and (iii) measurements, made by a user wireless terminal, of the power of each of the downlink control channel radio signals transmitted by each of the reference radios to generate an estimate of the location of the user wireless terminal.

Abstract: A location engine uses the empirical measurements made by a scouting wireless terminal (i) to discover the existence of a reference radio within a geographic region; (ii) to generate an estimate of the location of the newly-discovered reference radio, and (iii) to generate an estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio. The location engine then uses: (i) the estimate of the location of the newly-discovered reference radio, and (ii) the estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio, and (iii) measurements, made by a user wireless terminal, of the power of each of the downlink control channel radio signals transmitted by each of the reference radios to generate an estimate of the location of the user wireless terminal.

Abstract: A location engine uses the empirical measurements made by a scouting wireless terminal (i) to discover the existence of a reference radio within a geographic region; (ii) to generate an estimate of the location of the newly-discovered reference radio, and (iii) to generate an estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio. The location engine then uses: (i) the estimate of the location of the newly-discovered reference radio, and (ii) the estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio, and (iii) measurements, made by a user wireless terminal, of the power of each of the downlink control channel radio signals transmitted by each of the reference radios to generate an estimate of the location of the user wireless terminal.

Abstract: A wireless telecommunication system is described that denies wireless telecommunication service to a wireless terminal in a proscribed area (e.g., prison, military installation, academic testing center, school, etc.). The system comprises an adjunct called a “service sentry.” The service sentry uses measurements of the location-dependent traits of the radio signals transmitted to, and received from, each wireless terminal in its purview to generate an estimate of the location of the wireless terminal. When the service sentry estimates that the wireless terminal has entered the proscribed area, it requests that the wireless switching center that services the proscribed area deny service to the wireless terminal. When the service sentry estimates that the wireless terminal has exited the proscribed area, it requests that the wireless switching center that services the proscribed area restore service to the wireless terminal.

Abstract: A method for performing contact tracing. An analysis system performing the method receives geo-temporal data comprising location data points for various wireless terminals, including the wireless terminals being used by people diagnosed as having a specified disease and the wireless terminals of others, one of whom having possibly infected those diagnosed with the disease. Based on filtering the geo-temporal data, the analysis system generates relatively-condensed mobility profiles that are representative of each person's locations and movements, and analyzes the mobility profiles. Through careful selections of various parameters based on the disease that is being analyzed, the mobility profiles are used instead of the relatively large amounts of geo-temporal data, to represent users of wireless terminals and to determine their interactions in regard to disease transmission.

Abstract: A wireless telecommunication system is described that denies wireless telecommunication service to a wireless terminal in a proscribed area (e.g., prison, military installation, academic testing center, school, etc.). The system comprises an adjunct called a “service sentry.” The service sentry uses measurements of the location-dependent traits of the radio signals transmitted to, and received from, each wireless terminal in its purview to generate an estimate of the location of the wireless terminal. When the service sentry estimates that the wireless terminal has entered the proscribed area, it requests that the wireless switching center that services the proscribed area deny service to the wireless terminal. When the service sentry estimates that the wireless terminal has exited the proscribed area, it requests that the wireless switching center that services the proscribed area restore service to the wireless terminal.

Abstract: A method for performing contact tracing. An analysis system performing the method receives geo-temporal data comprising location data points for various wireless terminals, including the wireless terminal being used by a person diagnosed as having a specified disease and the wireless terminals of people who possibly have come in contact with the infected person. Based on filtering the geo-temporal data, the analysis system generates relatively-condensed mobility profiles that are representative of each person's locations and movements, and analyzes the mobility profiles. Through careful selections of various parameters based on the disease that is being analyzed, the mobility profiles are used instead of the relatively large amounts of geo-temporal data, to represent users of wireless terminals and to determine their interactions in regard to disease transmission.

Abstract: A method for estimating the pressure measurement bias of a barometric sensor in a wireless terminal. A location engine using the method generates an enhanced estimate of the measurement bias. The location engine generates the enhanced estimate based in part on relatively coarse estimates of the elevation of the wireless terminal. Each coarse estimate of elevation is often generated from noisy measurements, such as measurements of signals transmitted by Global Positioning System (GPS) satellites, and has an associated uncertainty. The location engine accounts for the uncertainty in these estimates of elevation by applying an optimal estimation technique, such as Kalman filtering, and by compensating for environment-related effects. Compensating Includes filtering across a plurality of lateral locations and imposing a lower bound of bias uncertainty at the lateral locations.

Abstract: A method for estimating the pressure measurement bias of a barometric sensor in a wireless terminal. A location engine using the method generates an enhanced estimate of the measurement bias. The location engine generates the enhanced estimate based in part on relatively coarse estimates of the elevation of the wireless terminal. The coarse estimates are used to generate instantaneous estimates of measurement bias and bias uncertainty. As needed, the location engine adjusts the instantaneous estimate of bias uncertainty, in order to reflect an instantaneous estimate of measurement bias that is recognized as being in error. The adjustment is based on what is expected as a probable measurement bias value for the particular wireless terminal. Once the location engine generates the enhanced estimate of measurement bias, it can generate improved estimates of elevation of the wireless terminal.

Abstract: A location engine uses the empirical measurements made by a scouting wireless terminal (i) to discover the existence of a reference radio within a geographic region; (ii) to generate an estimate of the location of the newly-discovered reference radio, and (iii) to generate an estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio. The location engine then uses: (i) the estimate of the location of the newly-discovered reference radio, and (ii) the estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio, and (iii) measurements, made by a user wireless terminal, of the power of each of the downlink control channel radio signals transmitted by each of the reference radios to generate an estimate of the location of the user wireless terminal.

Abstract: A location engine uses the empirical measurements made by a scouting wireless terminal (i) to discover the existence of a reference radio within a geographic region; (ii) to generate an estimate of the location of the newly-discovered reference radio, and (iii) to generate an estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio. The location engine then uses: (i) the estimate of the location of the newly-discovered reference radio, and (ii) the estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio, and (iii) measurements, made by a user wireless terminal, of the power of each of the downlink control channel radio signals transmitted by each of the reference radios to generate an estimate of the location of the user wireless terminal.

Abstract: A location engine uses the empirical measurements made by a scouting wireless terminal (i) to discover the existence of a reference radio within a geographic region; (ii) to generate an estimate of the location of the newly-discovered reference radio, and (iii) to generate an estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio. The location engine then uses: (i) the estimate of the location of the newly-discovered reference radio, and (ii) the estimate of the transmission power of the downlink control channel radio signal transmitted by the newly-discovered reference radio, and (iii) measurements, made by a user wireless terminal, of the power of each of the downlink control channel radio signals transmitted by each of the reference radios to generate an estimate of the location of the user wireless terminal.

Abstract: A technique for detecting the occurrence of an event, and for estimating other event-related information, by analyzing the barometric pressure in the vicinity of one or more wireless terminals. The disclosed detection technique is based on the recognition that the barometric sensor on various wireless terminals, such as smartphones, is capable of measuring very subtle changes in the atmospheric pressure. The disclosed detection technique is also based on the additional recognition of how some of the changes in the atmospheric pressure, as measured by a wireless terminal, correlate to various events that occur within a building or other defined area. For example, the disclosed technique can detect an entry door opening or closing by analyzing a resultant pressure wave having a particular transient that is perceptible by one or more wireless terminals in the area and analyzed by a detection engine.

Abstract: A method for estimating the pressure measurement bias of a barometric sensor in a wireless terminal. A location engine using the method generates an enhanced estimate of the measurement bias. The location engine generates the enhanced estimate based in part on Global Navigation Satellite System (GNSS)-based estimates of the elevation of the wireless terminal, which the terminal generates as it concurrently makes barometric pressure measurements. Each GNSS-based estimate of elevation is often generated from noisy measurements and has an associated uncertainty. The location engine accounts for the uncertainty in the GNSS estimates of elevation by applying an optimal estimation technique, such as Kalman filtering, on the biased pressure measurements and the GNSS-based estimates.

Abstract: A method for estimating the pressure measurement bias of a barometric sensor in a wireless terminal. A location engine using the method generates an enhanced estimate of the measurement bias. The location engine generates the enhanced estimate based in part on relatively coarse estimates of the elevation of the wireless terminal. Each coarse estimate of elevation is often generated from noisy measurements, such as measurements of signals transmitted by Global Positioning System (GPS) satellites, and has an associated uncertainty. The location engine accounts for the uncertainty in these estimates of elevation by applying an optimal estimation technique, such as Kalman filtering, and by compensating for environment-related effects. Compensating includes filtering across a plurality of lateral locations and imposing a lower bound of bias uncertainty at the lateral locations.

Abstract: A method for estimating the pressure measurement bias of a barometric sensor in a wireless terminal. A location engine using the method generates an enhanced estimate of the measurement bias. The location engine generates the enhanced estimate based in part on relatively coarse estimates of the elevation of the wireless terminal. The coarse estimates are used to generate instantaneous estimates of measurement bias and bias uncertainty. As needed, the location engine adjusts the instantaneous estimate of bias uncertainty, in order to reflect an instantaneous estimate of measurement bias that is recognized as being in error. The adjustment is based on what is expected as a probable measurement bias value for the particular wireless terminal. Once the location engine generates the enhanced estimate of measurement bias, it can generate improved estimates of elevation of the wireless terminal.

Abstract: A method for providing an enhanced estimate of reference barometric pressure. The method uses multiple, dissimilar pressure references, such as in airport weather stations, personal weather stations, and wireless terminals such as smartphones, in order to provide the enhanced estimate of reference barometric pressure. The method generates an enhanced estimate of reference barometric pressure based on a first estimate of reference barometric pressure from a first pressure reference network made up of airport weather stations, for example. The method also uses a second estimate of reference barometric pressure from a second pressure reference network made of up personal weather stations, for example, and a third estimate of reference barometric pressure, also from the second network. The first, second, and third estimates of reference barometric pressure are combined such that both measurement accuracy and timeliness are improved in the resulting, enhanced estimate.