Apparatus for frequency correction in a frequency synthesizer

Details Apparatus for frequency correction in a frequency synthesizer Apparatus for frequency correction in a frequency synthesizer

1984-06-24

1986-07-22

LaRoche, Eugene R.

Modulators

Amplitude modulator

Nonlinear device controlled by modulating signal

331 1A, 331 2, 331 14, 331 16, 331 77, 331 25, 455 76, H03C 300

Patent

active

046022252

ABSTRACT:
The present invention provides apparatus and a method for determining and correcting frequency offset for use in a frequency synthesizer to provide external control and DC frequency modulation of the synthesizer output frequency. The technique provides DCFM capability by unlocking a phase-lock loop (PLL) which provides the synthesizer reference frequency and making the PLL oscillator (VCO) tune line available for external inputs. Utilizing a frequency counting circuit, the exact output frequency of the VCO is determined. The desired VCO frequency is compared with the actual VCO frequency to derive an error signal proportional to any offset in the VCO frequency resulting from unlocking the PLL. The error signal is then utilized to compensate (the synthesizer output signal) for any frequency change as a result of unlocking the PLL.

REFERENCES:
patent: 4105946 (1978-08-01), Ikeda
patent: 4105948 (1978-08-01), Wolkstein
patent: 4320357 (1982-03-01), Wulfsberg et al.

Affiliated with

Also associated with

Rating

Apparatus for frequency correction in a frequency synthesizer does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Apparatus for frequency correction in a frequency synthesizer, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus for frequency correction in a frequency synthesizer will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-868019