Method and apparatus for efficient GPS assistance in a communication system
First Claim
1. A server for calculating information that assists in locating the position of satellites, including:
- a) an output port capable of outputting an Almanac and satellite location information, including information regarding the difference between satellite clock corrections and locations computed based upon Almanac and Ephemeris data; and
b) a processor, coupled to an output port, capable of;
1) computing the location of a satellite based upon the Almanac;
2) computing the satellite clock correction based upon the Almanac;
3) computing the location of the satellite based upon the Ephemeris;
4) computing the satellite clock correction based upon the Ephemeris; and
5) computing the difference between the location and satellite clock corrections which were computed based upon the Almanac and the Ephemeris.
1 Assignment
0 Petitions
Accused Products
Abstract
A method and apparatus for efficiently transmitting location assistance information to a mobile communication device over a control channel with a minimal impact on the capacity of the control channel. A position location server provides a difference between satellite locations which have been computed using Almanac data and then Ephemeris data. Sending only the difference between the locations and satellite clock corrections computed using the two different data types, the total amount of information to be transmitted to a mobile communication device is significantly reduced. Furthermore, by providing rate of change information, the method and apparatus allows the location assistance information to remain valid for a relatively long time after it is has been received by the mobile communication device.
230 Citations
33 Claims
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1. A server for calculating information that assists in locating the position of satellites, including:
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a) an output port capable of outputting an Almanac and satellite location information, including information regarding the difference between satellite clock corrections and locations computed based upon Almanac and Ephemeris data; and b) a processor, coupled to an output port, capable of; 1) computing the location of a satellite based upon the Almanac; 2) computing the satellite clock correction based upon the Almanac; 3) computing the location of the satellite based upon the Ephemeris; 4) computing the satellite clock correction based upon the Ephemeris; and 5) computing the difference between the location and satellite clock corrections which were computed based upon the Almanac and the Ephemeris.
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2. A method for calculating the position of a satellite at a first location time, including the steps of:
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a) transmitting Almanac data to a mobile communication device; b) calculating remotely from the mobile communication device, the location of the satellite at the first location time using the transmitted Almanac data; c) calculating remotely from the mobile communication device, the satellite clock correction for the satellite at the first location time using the transmitted Almanac data; d) calculating remotely from the mobile communication device, the location of the satellite at the first location time using Ephemeris data; e) calculating remotely from the mobile communication device, the satellite clock correction for the satellite at the first location time using the Ephemeris data; f) calculating remotely from the mobile communication device, location differences as the difference between the location determined from the transmitted Almanac data and the location computed using the Ephemeris data; and g) calculating remotely from the mobile communication device, satellite clock differences as the difference between the satellite clock correction determined from the transmitted Almanac data and the satellite clock correction determined from the Ephemeris data. - View Dependent Claims (3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33)
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Specification