Carrier lock detector

Details Carrier lock detector Carrier lock detector

1976-10-13

1978-05-02

Curtis, Marshall M.

Telegraphy

Code transmitters

Rotary contact

325341, 329111, 329122, 340207P, 340253Y, G08B 2100

Patent

active

040876284

ABSTRACT:
Apparatus for indicating a phase lock condition between an incoming multiphase carrier signal and a local oscillator in a phase-locked loop demodulator. A phase error signal is generated by phase comparing the carrier signal and the local oscillator signal. The phase error signal is rectified and the result detected for a range of values that indicate a phase lock condition. Phase lock exists when the phase error signal is within selected voltage ranges. After detection, the error signal is low-pass filtered and compared to a predetermined threshold value to generate a phase-lock indication signal. In the last two steps, an indication signal is generated to signify that the phase error signal is in the range of voltage values corresponding to phase lock for a greater percentage of time than it is within this range with the loop is not phase locked.

REFERENCES:
patent: 2926344 (1960-02-01), Koehler
patent: 3758852 (1973-09-01), Nowell et al.
patent: 3838294 (1974-09-01), Leete
Phase-Locked Loop Includes Lock Indicator; Connelly et al. Electronics; vol. 47, #18, pp. 112-113; 9/74; McGraw-Hill.
How Phase-Locked Loops Work; Cohen; Popular Electronics vol. 7, #2; pp. 32-34; 2/75; Ziff-Davis Publ.

Affiliated with

Also associated with

Rating

Carrier lock detector does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Carrier lock detector, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Carrier lock detector will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2159540