摘要:
A system and method for determining whether a wireless device has transmitted one or more forged satellite measurements. An estimated location of a wireless device may be determined as a function of signals from a cellular network. For each one of a first set of satellites from which the wireless device receives a signal, expected frequency information may be determined as a function of the estimated location, actual frequency information may be measured, and the expected frequency information compared with the measured frequency information. One or more satellite measurements received from the wireless device may then be identified as forged if a difference between the expected and measured frequency information is greater than a predetermined threshold.
摘要:
A system and method for determining the location of a wireless device. A boundary for an approximate area in which the wireless device is located is determined and a plurality of satellites may be determined as a function of the boundary. Assistance data is transmitted to the device which includes information from the plurality of satellites, and the location of the wireless device may be determined from the information. In one embodiment, if the number of the plurality of satellites is greater than a predetermined threshold then the number of satellites may be reduced as a function of one or more of the elevation of each satellite above the horizon, a distance between each satellite to one or more other satellites, and an altitude of each satellite.
摘要:
A system and method for detecting one or more forged satellite measurements transmitted from a wireless device. Information may be transmitted to a wireless device, the information including a request that the wireless device provide a portion of a navigation data message from one or more satellites to a location determining system. The one or more satellite measurements and the portion of the navigation data message may be received from the wireless device. The navigation data message may be determined as a function of information from a reference network. The determined navigation data message may then be compared with the received navigation data message portion to thereby determine whether any of the one or more satellite measurements transmitted by the device have been forged.
摘要:
A system and method for determining whether a wireless device has transmitted one or more forged satellite measurements. An estimated location of the wireless device may be determined as a function of information from a cellular network. Acquisition assistance data may be determined for a first set of satellites as a function of the estimated location, the assistance data including an uncertainty window. If measured code phase information in the satellite measurements substantially correlates to the uncertainty window, then the wireless device may be transmitting forged satellite measurements.
摘要:
A system and method for estimating the location of a wireless device. A set of satellites may be determined as a function of an approximate area in which the wireless device is located. Assistance data is transmitted to the device including information from the set of satellites, and a location of the device may be estimated from the information where the assistance data prevents the wireless device from searching for signals from one or more satellites in the set of satellites. The one or more satellites may be an operable satellite but signals therefrom cannot be measured or acquired by the wireless device.
摘要:
A system and method for detecting one or more forged satellite measurements transmitted from a wireless device. Information may be transmitted to a wireless device, the information including a request that the wireless device provide a portion of a navigation data message from one or more satellites to a location determining system. The one or more satellite measurements and the portion of the navigation data message may be received from the wireless device. The navigation data message may be determined as a function of information from a reference network. The determined navigation data message may then be compared with the received navigation data message portion to thereby determine whether any of the one or more satellite measurements transmitted by the device have been forged.
摘要:
A system and method for determining whether a wireless device has transmitted one or more forged satellite measurements. An estimated location of a wireless device may be determined as a function of signals from a cellular network. For each one of a first set of satellites from which the wireless device receives a signal, expected frequency information may be determined as a function of the estimated location, actual frequency information may be measured, and the expected frequency information compared with the measured frequency information. One or more satellite measurements received from the wireless device may then be identified as forged if a difference between the expected and measured frequency information is greater than a predetermined threshold.
摘要:
A system and method for determining the location of a wireless device. A boundary for an approximate area in which the wireless device is located is determined and a plurality of satellites may be determined as a function of the boundary. Assistance data is transmitted to the device which includes information from the plurality of satellites, and the location of the wireless device may be determined from the information. In one embodiment, if the number of the plurality of satellites is greater than a predetermined threshold then the number of satellites may be reduced as a function of one or more of the elevation of each satellite above the horizon, a distance between each satellite to one or more other satellites, and an altitude of each satellite.
摘要:
A system and method for determining whether a wireless device has transmitted one or more forged satellite measurements. An estimated location of the wireless device may be determined as a function of information from a cellular network. Acquisition assistance data may be determined for a first set of satellites as a function of the estimated location, the assistance data including an uncertainty window. If measured code phase information in the satellite measurements substantially correlates to the uncertainty window, then the wireless device may be transmitting forged satellite measurements.
摘要:
A system and method for estimating the position of a mobile device using information from a constellation of satellites. A first set of satellites of the constellation may be selected and then a second set of satellites of the constellation may be selected as a function of signals received from the first set of satellites. Data may be transmitted to the mobile device based on signals received from the second set of satellites, and a location of the device estimated based on the data. One embodiment may select the second set as a function of an intersection of coverage areas of ones of the first set of satellites. Another embodiment may select the second set as a function of one or more satellites that are not occluded by the Earth from one or more of the first set of satellites.