04578678 is referenced by 161 patents and cites 2 patents.

A GPS receiver having a number of channels, one for each of a plurality of satellites, receives an aggregate of pseudorange code time division modulated signals from some or all satellites and converts the aggregate to baseband and then to digital form for separate processing in the separate channels, each of which includes a complex mixer for adjustment of the baseband signal to a smooth estimate of frequency, .omega., for the next measurement interval, and an N-lag cross correlator which receives a replica of the pseudorange code adjusted for a smoothed estimate of the pseudorange (delay), .tau.. A fast Fourier transform processor computes the signal energy as a function of Doppler frequency for each correlation lag, and a range and frequency estimator computes estimates of pseudorange, .tau., and frequency, .omega.. These raw estimates from all channels are used to estimate receiver position, velocity, clock offset and clock rate offset in a conventional navigation and control unit, and based on the total solution, that unit computes smoothed estimates, .tau. and .omega., for the next measurement interval. The smoothed estimates are thus based on the total solution, and not just on the separate estimates of the satellites, all without the use of any phase-locked loop.

Title
High dynamic global positioning system receiver
Application Number
6/551536
Publication Number
4578678
Application Date
November 14, 1983
Publication Date
March 25, 1986
Inventor
William J Hurd
La Canada
CA, US
Agent
Thomas H Jones
John R Manning
Paul F McCaul
Assignee
The United States of America represented by the United States National Aeronautics and Space Administration
DC, US
IPC
H04B 7/185
G01S 5/02
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