Abstract: Different types of position fixes may be used to determine the location of a mobile station in a wireless communication system. The position fixes include terrestrial, or network, based techniques, and non-network based techniques, such as satellite, based techniques. An apparatus and method are presented by which different position fixes may be selected, based on the performance of a particular position fix in a particular mobile remote unit.

Abstract: Methods and apparatuses are provided that may be implemented in various electronic devices to identify suspect measurements for use in a position/velocity/time estimation filter and provide corresponding validated measurements that may be either operatively re-weighted in some manner or operatively one-sided isolated in some manner when subsequently considered by the position/velocity/time estimation filter.

Abstract: Methods and apparatuses are provided that may be implemented various electronic devices to affect application of a filtering model used for obtaining a navigation solution. In particular, signal characteristics of one or more received signals are used for selecting application of a particular filtering model from a plurality of filtering models.

Abstract: A method and apparatus to utilize a set of measurements (either partial or compete) to improve the accuracy of an initial position estimate for a wireless terminal. The initial position estimate for the terminal is first obtained (e.g., based on a cell-ID or an enhanced cell-ID solution). Measurements are obtained for the terminal. The initial position estimate is then updated with the measurements to obtain a revised position estimate for the terminal. The updating may be performed by (1) deriving a measurement vector based on the initial position estimate and the measurements, (2) forming an observation matrix for the measurements, (3) determining a matrix of weights, (4) deriving a correction vector based on the measurement vector, the observation matrix, and the weight matrix, and (5) updating the initial position estimate with the correction vector.

Abstract: Methods and apparatuses are provided which may be enabled within and/or for use with a Satellite Positioning System (SPS) receiver and/or other like apparatuses or device(s) to perform a rapid search startup process.

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: In a wireless mobile communication system having a position determination service, base station information is stored in a base station almanac. In addition to the position of the base station antenna, forward link delay calibration, and base station identification information, a base station almanac record includes the center location of the base station sector coverage area, the maximum range of the base station antenna, the terrain average height over the sector coverage area, the terrain height standard deviation over the sector coverage area, round-trip delay (RTD) calibration information, repeater information, pseudo-random noise (PN) increments, uncertainty in the base station antenna position, uncertainty in the forward-link delay calibration, and uncertainty in the round-trip delay calibration.

Abstract: A method and apparatus to utilize a set of measurements (either partial or compete) to improve the accuracy of an initial position estimate for a wireless terminal. The initial position estimate for the terminal is first obtained (e.g., based on a cell-ID or an enhanced cell-ID solution). Measurements are obtained for the terminal. The initial position estimate is then updated with the measurements to obtain a revised position estimate for the terminal. The updating may be performed by (1) deriving a measurement vector based on the initial position estimate and the measurements, (2) forming an observation matrix for the measurements, (3) determining a matrix of weights, (4) deriving a correction vector based on the measurement vector, the observation matrix, and the weight matrix, and (5) updating the initial position estimate with the correction vector.

Abstract: Methods and apparatuses are provided for use with mode switchable navigation radios and the like. The methods and apparatuses may be implemented to selectively switch between certain operating modes based, at least in part, a mode-switching test that takes into consideration one or more non-timed test conditions to determine if mode-switching may be enabled.

Abstract: A method and apparatus for using a predetermined portion of terrain elevation maps in a database for aiding in computing a three-dimensional position of a wireless station. Instead of using the entire terrain model of the earth or an entire country, the database consists of an incomplete model, which includes only the most populous areas or specific regions. This reduces the size of the information in the database, which in turn reduces the amount of time to compute the positions of the wireless device.

Abstract: In general, this disclosure is directed to techniques for computing a positioning solution for a mobile unit based on signals received from the satellite navigation system and the wireless communication system. The techniques allow for, and resolve, a synchronization bias that constrains a system time for the satellite navigation system and a system time for the wireless communication system relative to each other. The mobile unit may utilize the defined constraint to compute a position solution in environments where additional independent measurements would otherwise be required. The mobile unit may incorporate Receiver Autonomous Integrity Monitoring (RAIM) functionality to validate the position and time solutions derived from each of received signals. According to the techniques described herein, the mobile unit may be able to utilize the defined synchronization bias to apply RAIM or similar techniques in environments where such techniques would otherwise be indeterminate.

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: 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: In general, this disclosure is directed to techniques for computing a positioning solution for a mobile unit based on signals received from the satellite navigation system and the wireless communication system. The techniques allow for, and resolve, a synchronization bias that constrains a system time for the satellite navigation system and a system time for the wireless communication system relative to each other. The mobile unit may utilize the defined constraint to compute a position solution in environments where additional independent measurements would otherwise be required. The mobile unit may incorporate Receiver Autonomous Integrity Monitoring (RAIM) functionality to validate the position and time solutions derived from each of received signals. According to the techniques described herein, the mobile unit may be able to utilize the defined synchronization bias to apply RAIM or similar techniques in environments where such techniques would otherwise be indeterminate.

Abstract: In a wireless mobile communication system having a position determination service, base station information is stored in a base station almanac. In addition to the position of the base station antenna, forward link delay calibration, and base station identification information, a base station almanac record includes the center location of the base station sector coverage area, the maximum range of the base station antenna, the terrain average height over the sector coverage area, the terrain height standard deviation over the sector coverage area, round-trip delay (RTD) calibration information, repeater information, pseudo-random noise (PN) increments, uncertainty in the base station antenna position, uncertainty in the forward-link delay calibration, and uncertainty in the round-trip delay calibration.