Abstract: A mobile communications device uses a method for determining position that involves a positioning filter, such as a Kalman filter, which is initialized with measurements from reference stations such as satellite vehicles and/or base stations which may be acquired during different epochs. Accordingly, the positioning filter may be used for position estimation without the need to first acquire at least three different signals during the same measurement epoch.

Abstract: Methods and apparatuses for the processing of false alarms in position determination. At least one embodiment of the present invention estimates and uses measurement false alarm probabilities in the position determination process. In one embodiment, the estimated measurement false alarm probabilities are combined to determine the reliability of the determined position solution or the reliability of the set of measurements as a collection. In one embodiment, the estimated measurement false alarm probabilities are used in the isolation and elimination of faulty measurements. For example, the traditional geometry based metric for identifying a faulty measurement is further weighted according to the measurement false alarm probabilities in order to determine the faulty measurement.

Abstract: A method and apparatus for creating and using a base station almanac for position determination is described. The base station almanac includes a number of records, where each record can describe a sector or a transmitter (e.g., a base station or a repeater) in a wireless communication network. Each record includes a protocol type field that indicates the one or more protocols supported by the record (e.g., IS-801, J-GSM, STD-36, GSM, W-CDMA, and so on). Each record also includes a unique sector identifier for the sector/transmitter for each supported protocol, where each identifier is defined based on the associated protocol. A record may also include multiple maximum antenna ranges (MARs), where each MAR is associated with a respective reference power level. One of the multiple MARs can be selected for use for position determination depending on received signal strength. The base station almanac further includes other features.

Abstract: A system and method are disclosed by which a base transceiver station (BTS) may be uniquely identified. When attempting to determine the location of a mobile unit using signal from multiple BTSs, it is critical that the BTSs be uniquely identified and their position accurately determined. In many cases, the signals received from the BTSs provide limited identification information and cannot be used to uniquely to identify the BTS from which a signal has been received. The present invention uses available information to generate a candidate list and to determine therefrom the most likely candidates for the Measurement BTSs. Based on this information, the system analyzes cell coverage overlap and relative phase delay to determine the likelihood of a candidate BTS being the actual BTS from which a signal is received. As candidate BTSs are uniquely identified, it is possible to use this additional identification information in an iterative process to further identify additional candidate BTSs.

Abstract: In a wireless communication network, base station antenna positions and time offsets are stored in a base station almanac data base along with other information used for obtaining the most reliable mobile station position fixes under a variety of conditions. The system uses the position fixes of mobile stations and terrestrial ranging information to determine base station antenna positions and base station timing offsets. The base station antenna positions are determined during normal mobile station position determinations, in order to maintain and improve the antenna location data, and to correct for change or relocation of the base station antennas. It is possible to recover quickly from a loss of cell sector identity during relocation of a base station antenna, and to ensure accuracy of mobile station position determination based on ranging from the base stations, and rapid acquisition of position data from mobile stations having global satellite receivers.

Abstract: A method and apparatus for creating and using a base station almanac for position determination is described. The base station almanac includes a number of records, where each record can describe a sector or a transmitter (e.g., a base station or a repeater) in a wireless communication network. Each record includes a protocol type field that indicates the one or more protocols supported by the record (e.g., IS-801, J-STD-36, GSM, W-CDMA, and so on). Each record also includes a unique sector identifier for the sector/transmitter for each supported protocol, where each identifier is defined based on the associated protocol. A record may also include multiple maximum antenna ranges (MARs), where each MAR is associated with a respective reference power level. One of the multiple MARs can be selected for use for position determination depending on received signal strength. The base station almanac further includes other features.

Abstract: A system and method examines the quality of a positioning signal acquisition assistance window of an assisted position location system. The fit of acquisition assistance windows is examined using a posteriori knowledge of specific, or hypothetical, position measurements from a mobile station. A base station almanac manager compares mobile station measurement data to acquisition assistance window data, records an outcome based upon the comparison including a window quality value (WQ), or range of window quality values. Source data used in the generation of acquisition assistance windows is adjusted according to the window quality value.

Abstract: A system, method and device are provided which determine the position of a mobile station in connection with consulting signal delay transmission data from an almanac for the purpose of identifying the nearest set of base stations. Thereafter, the position of the mobile station is determined using multilateration.

Abstract: A system and method are disclosed by which a base transceiver station (BTS) may be uniquely identified. When attempting to determine the location of a mobile unit using signal from multiple BTSs, it is critical that the BTSs be uniquely identified and their position accurately determined. In many cases, the signals received from the BTSs provide limited identification information and cannot be used to uniquely to identify the BTS from which a signal has been received. The present invention uses available information to generate a candidate list and to determine therefrom the most likely candidates for the Measurement BTSs. Based on this information, the system analyzes cell coverage overlap and relative phase delay to determine the likelihood of a candidate BTS being the actual BTS from which a signal is received. As candidate BTSs are uniquely identified, it is possible to use this additional identification information in an iterative process to further identify additional candidate BTSs.

Abstract: Techniques to estimate the position of a wireless terminal. In a method, the identities of a number of transmitters (e.g., BTSs) to be used to estimate the position are initially received. Expected areas for these transmitters are then determined. The expected area associated with each transmitter is indicative of an area where the terminal is likely to be located given that the signal from the transmitter is received by the terminal. Each expected area may comprise a location (e.g., the expected area center) to be used as an estimated position of the terminal and an uncertainty (or error estimate) associated with that estimated position. The expected areas for the transmitters are then combined (e.g., based on a weighted average) to determine a combined expected area, which is then provided as the estimate of the position of the terminal.

Abstract: Methods and apparatuses for position determination and other operations. In one embodiment of the present invention, a mobile station uses wireless signals from a plurality of wireless networks (e.g., with different air interfaces and/or operated by different service providers) for position determination (e.g., for data communication, for obtaining time and/or frequency information, for range measurement, for sector or altitude estimation). In one embodiment of the present invention, mobile stations are used to harvest statistical data about wireless access points (e.g., the locations of mobile stations that have received signals from the wireless access points, such as from cellular base stations, wireless local area network access points, repeaters for positioning signals, or other wireless communication transmitters) and to derive location information (e.g., position and coverage area of the wireless access points) for the wireless networks from the collected statistical data.

Abstract: A method and apparatus for creating and using a base station almanac for position determination is described. The base station almanac includes a number of records, where each record can describe a sector or a transmitter (e.g., a base station or a repeater) in a wireless communication network. Each record includes a protocol type field that indicates the one or more protocols supported by the record (e.g., IS-801, J-STD-36, GSM, W-CDMA, and so on). Each record also includes a unique sector identifier for the sector/transmitter for each supported protocol, where each identifier is defined based on the associated protocol. A record may also include multiple maximum antenna ranges (MARs), where each MAR is associated with a respective reference power level. One of the multiple MARs can be selected for use for position determination depending on received signal strength. The base station almanac further includes other features.

Abstract: A system and method are disclosed by which a base transceiver station (BTS) may be uniquely identified. When attempting to determine the location of a mobile unit using signal from multiple BTSs, it is critical that the BTSs be uniquely identified and their position accurately determined. In many cases, the signals received from the BTSs provide limited identification information and cannot be used to uniquely to identify the BTS from which a signal has been received. The present invention uses available information to generate a candidate list and to determine therefrom the most likely candidates for the Measurement BTSs. Based on this information, the system analyzes cell coverage overlap and relative phase delay to determine the likelihood of a candidate BTS being the actual BTS from which a signal is received. As candidate BTSs are uniquely identified, it is possible to use this additional identification information in an iterative process to further identify additional candidate BTSs.

Abstract: Techniques to estimate the position of a wireless terminal. In a method, the identities of a number of transmitters (e.g., BTSs) to be used to estimate the position are initially received. Expected areas for these transmitters are then determined. The expected area associated with each transmitter is indicative of an area where the terminal is likely to be located given that the signal from the transmitter is received by the terminal. Each expected area may comprise a location (e.g., the expected area center) to be used as an estimated position of the terminal and an uncertainty (or error estimate) associated with that estimated position. The expected areas for the transmitters are then combined (e.g., based on a weighted average) to determine a combined expected area, which is then provided as the estimate of the position of the terminal.

Abstract: Methods and apparatuses for location determination in wireless assisted positioning systems. In one aspect of the disclosed method and apparatus, a method to determine a position of a mobile device in a positioning system includes: computing a second estimated position of a mobile device using a first assumed geometric relationship for a location of the mobile device in relation to a navigational transmitter (e.g., a basestation, a pseudolite, or a Satellite Positioning System (SPS) satellite). The first geometric relationship is linearly independent from the altitude of the mobile device (e.g., obtained from an altitude aiding) and a second geometric relationship based on range information (e.g., a range from the mobile device to the navigational transmitter, a pseudorange, an arrival time, or a round trip time) measured with respect to the navigational transmitter.

Abstract: In a wireless telecommunication network, hybrid (GPS and AFLT) mobile stations provide redundant position information, which is used for time base calibration and/or correction of position measurements. Every mobile station (i.e., handset or cellular phone) can be used as a test instrument, and data from regular wireless phone calls can be supplemented by data from drive-around field test units. The time base and/or position offsets are stored in a base station almanac data base along with other information used for obtaining the most reliable position fixes under a variety of conditions. An automatic system is provided for creating, updating, and maintaining the base station almanac data base. The automatic system not only characterizes the performance of the wireless network but also characterizes the performance of the position determination system. The automatic system provides performance feedback to system operators and customers.

Abstract: In a wireless communication network, base station antenna positions and time offsets are stored in a base station almanac data base along with other information used for obtaining the most reliable mobile station position fixes under a variety of conditions. The system uses the position fixes of mobile stations and terrestrial ranging information to determine base station antenna positions and base station timing offsets. The base station antenna positions are determined during normal mobile station position determinations, in order to maintain and improve the antenna location data, and to correct for change or relocation of the base station antennas. It is possible to recover quickly from a loss of cell sector identity during relocation of a base station antenna, and to ensure accuracy of mobile station position determination based on ranging from the base stations, and rapid acquisition of position data from mobile stations having global satellite receivers.

Abstract: A system and method are disclosed by which a base transceiver station (BTS) may be uniquely identified. When attempting to determine the location of a mobile unit using signal from multiple BTSs, it is critical that the BTSs be uniquely identified and their position accurately determined. In many cases, the signals received from the BTSs provide limited identification information and cannot be used to uniquely to identify the BTS from which a signal has been received. The present invention uses available information to generate a candidate list and to determine therefrom the most likely candidates for the Measurement BTSs. Based on this information, the system analyzes cell coverage overlap and relative phase delay to determine the likelihood of a candidate BTS being the actual BTS from which a signal is received. As candidate BTSs are uniquely identified, it is possible to use this additional identification information in an iterative process to further identify additional candidate BTSs.

Abstract: A method and system for performing attitude determination for an array of receivers in a navigational positioning system are described. A navigational positioning system includes an array of receiver antennas that simultaneously receive signals emitted from satellites or other fixed or moving sources. A first set of potential solutions for a first baseline vector and a second set of potential solutions for a second baseline vector determined. Each baseline vector corresponds to any pair of receiver antennas in the array. The baseline vector comprises both the scalar distance between the antennas and the orientation of the line between the antennas in a geospatial coordinate frame. In one embodiment, test results are obtained for at least two tests performed on each potential solution in a set of potential solution. Each potential solution in the sets of potential solutions is evaluated as a candidate for a correct solution for the corresponding baseline vector.

Abstract: A method and system for performing integer ambiguity resolution for navigational positioning systems are described. A navigational positioning system includes a pair of receivers with antennas that simultaneously receive signals emitted from satellites or other moving or fixed sources. Potential solutions for the baseline vector between the antennas are determined. Test results are obtained for at least two tests performed on each potential solution. Examples of such tests include comparing a code double difference with each carrier phase double difference and comparing each potential solution with information known about the antennas. Each one of the potential solutions is evaluated as a candidate for a correct solution for the baseline vector. The evaluation of each potential solution is based on every test result obtained for that potential solution without disqualifying any one of the potential solutions as a candidate for the correct solution based on any one test result.