Low-noise digitally tunable phase-locked loop frequency generato

Details Low-noise digitally tunable phase-locked loop frequency generato Low-noise digitally tunable phase-locked loop frequency generato

1981-12-08

1985-04-30

LaRoche, Eugene R.

Oscillators

Automatic frequency stabilization using a phase or frequency...

Plural oscillators controlled

331 10, 331 11, 331 16, 331 17, H03L 708, H03L 718

Patent

active

045147051

ABSTRACT:
A variable-frequency main oscillator of digitally tunable high output frequency f.sub.A is controlled by the integrated output voltage of a phase discriminator receiving on the one hand a relatively low comparison frequency and on the other hand a matching feedback frequency stepped down from output frequency f.sub.A by frequency division or by heterodyning with an auxiliary frequency f.sub.H of the same order of magnitude from an ancillary oscillator, a difference frequency f.sub.D =f.sub.A -f.sub.H is fed to a frequency discriminator delivering a corrective voltage, independent of that emitted by the phase discriminator through a filter network, to the control input of the main oscillator. A pair of frequency selectors varying the feedback frequency and/or the comparison frequency enable the output frequency f.sub.A to be adjusted in coarse and fine tuning steps, the coarse adjustments being also applied to the auxiliary frequency f.sub.H to limit the excursions of the difference frequency f.sub.D. In order to minimize shifts in the corrective voltage due to changes in the setting of the fine-tuning selector, a digital command generated by that selector is converted into an analog compensating voltage subtracted from the output voltage of the frequency discriminator.

REFERENCES:
patent: 3840822 (1974-10-01), Hoffmann
patent: 3872397 (1975-03-01), Hanneman
patent: 3875524 (1975-04-01), Harzer et al.
patent: 3956703 (1976-05-01), Noordanus et al.
patent: 4191930 (1980-03-01), Harzer
patent: 4318055 (1982-03-01), Hopwood et al.

Affiliated with

Also associated with

Rating

Low-noise digitally tunable phase-locked loop frequency generato does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Low-noise digitally tunable phase-locked loop frequency generato, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Low-noise digitally tunable phase-locked loop frequency generato will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1970742