04068199 is referenced by 34 patents and cites 3 patents.

Frequency modulating apparatus employing a phase-locked loop. An analog signal is sampled periodically and each sample is converted to a digital signal by an analog-to-digital converter. A constant is added to the digital signal and the sum is employed as the divisor of a programmable divider connected in the phase-locked loop between the output of the voltage controlled oscillator and an input of a phase detector. The output of the voltage controlled oscillator is also divided by an output divider and then filtered to provide a sinusoidal output signal. The resulting output signal is at a center frequency which is frequency modulated by the analog signal.

Title
Digital phase-locked loop frequency modulator
Application Number
5/753799
Publication Number
4068199
Application Date
December 23, 1976
Publication Date
January 10, 1978
Inventor
Herbert S Madoff
Sudbury
MA, US
Agent
Peter Xiarhos
Norman J O Malley
David M Keay
Assignee
GTE Sylvania Incorporated
CT, US
IPC
H03C 3/00
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