05119102 is referenced by 228 patents and cites 1 patents.

Signals from a number of NAVSTAR global positioning system (GPS) satellites (11,12,13,14) are received by a receiver (16) in a vehicle (15) and a segment of the signals is stored in a memory (18) prior to retransmission by a transmitter (19). A base station (35) receives these transmissions from the mobile unit using a first receiver (36). The base station also receives signals directly from the NAVSTAR GPS satellites using a second receiver (38). A control and calculating apparatus (37) within the base station can determine the ephemeris (course) information for the satellites and can measure the transmission times or propagation delays of signals between the satellites and the vehicle and with this information the control and calculating apparatus can calculate the position of the vehicle unit.

Title
Vehicle location system
Application Number
7/644792
Publication Number
5119102
Application Date
January 23, 1991
Publication Date
June 2, 1992
Inventor
Michael E Barnard
Reigate
GB
Agent
Lesley Rhyne
Assignee
U S Philips Corporation
NY, US
IPC
G01S 5/02
H04B 7/185
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