3819920 is referenced by 21 patents and cites 6 patents.

A digital frequency tracker for a Doppler navigation system in which the input is sampled, autocorrelation function values computed therefrom, and the values used in a Fourier series computation to obtain powers bracketing a center frequency. From these computations tracking and acquisition is provided by shifting the center frequency as a function of the computation until equal power occurs on both sides of the center frequency. Also shown are means to compute altitude by sampling at the FM modulation rate.

Title
Digital frequency tracker
Application Number
05/327,596
Publication Number
3819920
Application Date
January 29, 1973
Publication Date
June 25, 1974
Inventor
Goldfischer Lester I
Agent
Kennedy T W
Assignee
The Singer Company
IPC
G01r 23/02
G06f 15/34
G06F 17/15
G01S 13/58
G01S 13/34
G01S 13/00
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