Abstract: Techniques for using measurements made by UEs to improve network performance are described. In one aspect, RF parameters of cells may be determined by taking into account mobility of the UEs. Mobility information for the UEs may be determined based on measurement report messages (MRMs) sent by these UEs for handover. RF parameters such as antenna down-tilt, antenna orientation, antenna pattern, and/or pilot power of the cells may be determined based on the mobility information for the UEs. In another aspect, the RF parameters of cells may be dynamically adjusted based on loading conditions of cells. In yet another aspect, the location of a UE may be determined based on an MRM sent by the UE for handover. The MRM may include timing measurements for multiple cells. The location of the UE may be determined based on the timing measurements.

Abstract: Different types of position solutions may be used to determine the position of a mobile station (104) in a wireless communication system (101). The position solutions include terrestrial, or network (102, 103), based techniques and non-network, such as satellite (160), based techniques. An apparatus and method whereby different position solutions are selected based on a figure of merit of the different solutions in determining a position of a mobile remote unit (104).

Abstract: A method performs an update for a first device that consumes information with a known expiration time. The first device operates within a network that accommodates other devices also consuming the information. The method includes setting a time for the first device to refresh the information, the time to refresh being based on a pseudorandom time offset. The method also includes sending a refresh request to a resource for the data during the set time.

Abstract: Methods and apparatuses to generate and to access compressed and indexed elevations of Digital Elevation Models. In one aspect of the invention, a method to store elevation data includes: compressing elevation data of a first portion of a Digital Elevation Model (DEM) to generate first compressed elevation data; storing the first compressed elevation data in a storage location pointed to by a first index; and storing the first index. In another aspect of the invention, a method to retrieve elevation data includes: locating a first compressed portion of a Digital Elevation Model (DEM) using a first index; and decompressing the first compressed portion to retrieve first elevation data for at least one sample point in the Digital Elevation Model. The Digital Elevation Model has a plurality of compressed portions which includes the first compressed portion; and the first index points to a storage location where the first compressed portion is stored.

Abstract: A method and system for assisting mobile stations to locate a satellite use an efficient messaging format. A server computes a correction between coarse orbit data of a satellite and precise orbit data of the satellite. A coordinate system is chosen such that variation of the correction is substantially smooth over time. The server further approximates the correction with mathematical functions to reduce the number of bits necessary for transmission to a mobile station. The mobile station, upon receiving the coefficients, evaluates the mathematical functions using the coefficients and a time of applicability (e.g., the current time), converts the evaluated result to a standard coordinate system, and applies the conversion result to the coarse orbit data to obtain the precise orbit data.

Abstract: A system and method of preprocessing reference data in a reference assisted location technology are disclosed. A plurality of reference stations each provides reference data over a network to a preprocessing. The preprocessor analyzes the data from the multiple reference stations and eliminates multiples sets of redundant data. In addition, the preprocessor can perform quality assurance checks on the data as well as the status of the reference stations themselves. Non-redundant data may also be preprocessed to perform differential GPS calculations. The preprocessed data is transmitted to one or more position servers for additional processing and position determination.

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: Techniques for using measurements made by UEs to improve network performance are described. In one aspect, RF parameters of cells may be determined by taking into account mobility of the UEs. Mobility information for the UEs may be determined based on measurement report messages (MRMs) sent by these UEs for handover. RF parameters such as antenna down-tilt, antenna orientation, antenna pattern, and/or pilot power of the cells may be determined based on the mobility information for the UEs. In another aspect, the RF parameters of cells may be dynamically adjusted based on loading conditions of cells. In yet another aspect, the location of a UE may be determined based on an MRM sent by the UE for handover. The MRM may include timing measurements for multiple cells. The location of the UE may be determined based on the timing measurements.

Abstract: Different types of position solutions may be used to determine the position of a mobile station (104) in a wireless communication system (101). The position solutions include terrestrial, or network (102, 103), based techniques and non-network, such as satellite (160), based techniques. An apparatus and method whereby different position solutions are selected based on a figure of merit of the different solutions in determining a position of a mobile remote unit (104).

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: Methods and apparatuses to generate and to access compressed and indexed elevations of Digital Elevation Models. In one aspect of the invention, a method to store elevation data includes: compressing elevation data of a first portion of a Digital Elevation Model (DEM) to generate first compressed elevation data; storing the first compressed elevation data in a storage location pointed to by a first index; and storing the first index. In another aspect of the invention, a method to retrieve elevation data includes: locating a first compressed portion of a Digital Elevation Model (DEM) using a first index; and decompressing the first compressed portion to retrieve first elevation data for at least one sample point in the Digital Elevation Model. The Digital Elevation Model has a plurality of compressed portions which includes the first compressed portion; and the first index points to a storage location where the first compressed portion is stored.

Abstract: Methods and apparatuses to generate and to access compressed and indexed elevations of Digital Elevation Models. In one aspect of the invention, a method to store elevation data includes: compressing elevation data of a first portion of a Digital Elevation Model (DEM) to generate first compressed elevation data; storing the first compressed elevation data in a storage location pointed to by a first index; and storing the first index. In another aspect of the invention, a method to retrieve elevation data includes: locating a first compressed portion of a Digital Elevation Model (DEM) using a first index; and decompressing the first compressed portion to retrieve first elevation data for at least one sample point in the Digital Elevation Model. The Digital Elevation Model has a plurality of compressed portions which includes the first compressed portion; and the first index points to a storage location where the first compressed portion is stored.

Abstract: A system and method of preprocessing reference data in a reference assisted location technology are disclosed. A plurality of reference stations each provides reference data over a network to a preprocessing. The preprocessor analyzes the data from the multiple reference stations and eliminates multiples sets of redundant data. In addition, the preprocessor can perform quality assurance checks on the data as well as the status of the reference stations themselves. Non-redundant data may also be preprocessed to perform differential GPS calculations. The preprocessed data is transmitted to one or more position servers for additional processing and position determination.

Abstract: Methods and apparatuses to generate and to access compressed and indexed elevations of Digital Elevation Models. In one aspect of the invention, a method to store elevation data includes: compressing elevation data of a first portion of a Digital Elevation Model (DEM) to generate first compressed elevation data; storing the first compressed elevation data in a storage location pointed to by a first index; and storing the first index. In another aspect of the invention, a method to retrieve elevation data includes: locating a first compressed portion of a Digital Elevation Model (DEM) using a first index; and decompressing the first compressed portion to retrieve first elevation data for at least one sample point in the Digital Elevation Model. The Digital Elevation Model has a plurality of compressed portions which includes the first compressed portion; and the first index points to a storage location where the first compressed portion is stored.

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: 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: A method and system for rapidly initializing a rover unit in a networked system. In one embodiment, the present invention acquires rover unit initialization data at a reference station. In one embodiment, the rover unit initialization data is selected from the group consisting of: ephemeris data, almanac data, satellite health data, ionospheric data, UTC and GPS time and approximate rover position information. In the present embodiment, the present invention then communicatively couples the reference station to a server station having memory for storing the rover unit initialization data. After communicatively coupling the reference station to the server station, the present embodiment transfers the rover unit initialization data from the reference station to the server station. The present embodiment then communicatively couples the rover unit to the server station. Next, the present embodiment supplies the rover unit initialization data from the server station to the rover unit.

Abstract: A method for determining an improved position fix by performing postprocessing on a realtime differentially corrected GPS position. A remote rover unit containing a GPS receiver is used to determine a differentially corrected position according to measured pseudoranges and realtime pseudorange correction vectors is broadcast by a base station. The rover unit applies realtime corrections to measurements to determine a more accurate realtime differential position. It then stores the realtime differential position and the realtime pseudorange correction vector. Subsequently, postprocessing is performed to determine a postprocessed pseudorange correction vector. A difference vector representing the difference between the realtime pseudorange correction vector and the postprocessed pseudorange correction vector is then determined. This difference vector is applied to the realtime differential position to calculate a more accurate, improved position fix.

Abstract: A method for determining an improved position fix by performing postprocessing on a realtime differentially corrected GPS position. A remote rover unit containing a GPS receiver is used to determine a differentially corrected position according to measured pseudoranges and realtime pseudorange correction vectors is broadcast by a base station. The rover unit applies realtime corrections to measurements to determine a more accurate realtime differential position. It then stores the realtime differential position and the realtime pseudorange correction vector. Subsequently, postprocessing is performed to determine a postprocessed pseudorange correction vector. A difference vector representing the difference between the realtime pseudorange correction vector and the postprocessed pseudorange correction vector is then determined. This difference vector is applied to the realtime differential position to calculate a more accurate, improved position fix.