Pulse or digital communications – Synchronizers – Phase displacement – slip or jitter correction
Reexamination Certificate
2005-11-01
2005-11-01
Chin, Stephen (Department: 2634)
Pulse or digital communications
Synchronizers
Phase displacement, slip or jitter correction
Reexamination Certificate
active
06961400
ABSTRACT:
A frequency shift keyed (FSK) receiver for demodulating an incoming transmitted signal comprising: 1) a phase-locked loop for receiving an oscillator reference signal having a frequency F1 and generating a reference carrier frequency signal having a desired frequency N1(F1), wherein N1 may be a non-integer value, the phase-locked loop comprising: a) a phase detector having a first input for receiving the oscillator reference signal and a second input; and b) a frequency divider circuit for dividing an actual frequency of the reference carrier frequency signal by an adjustable integer value N2 applied to a control input of the frequency divider circuit to generate a feedback signal applied to the second input of the phase detector. The FSK receiver further comprises: 2) a frequency discriminator that receives the incoming transmitted signal and the reference carrier frequency signal and generates a correction signal corresponding to a difference between a center frequency of the incoming transmitted signal and the actual frequency of the reference carrier frequency signal; and 3) a delta-sigma modulator controlled by the correction signal operable to generate a sequence of integers having an average value of N2 over a defined time period, wherein the sequence of integers are applied to the control input of the frequency divider circuit.
REFERENCES:
patent: 5170131 (1992-12-01), Takahiro et al.
patent: 6011815 (2000-01-01), Eriksson et al.
patent: 6208211 (2001-03-01), Zipper et al.
patent: 6219397 (2001-04-01), Park
patent: 6236703 (2001-05-01), Riley
patent: 6249238 (2001-06-01), Steinlechner
Huff William J.
Malone Lawrence J.
Chin Stephen
Joseph Jaison
National Semiconductor Corporation
LandOfFree
Automatic frequency correction apparatus and method of... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Automatic frequency correction apparatus and method of..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Automatic frequency correction apparatus and method of... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3481441