Carrier detect and automatic loopback circuit

Details Carrier detect and automatic loopback circuit Carrier detect and automatic loopback circuit

1976-08-02

1978-11-28

Griffin, Robert L.

1791753R, H04B 1700

Patent

active

041278160

ABSTRACT:
A master station communicates with remote stations by respective transmit-receive pairs. Quadra-phase modulation is utilized, involving a carrier having two characteristic frequencies not present during bursts of a communicated signal, which bursts are known to last for a fixed duration. Signals on a receive pair are detected, and phase locked loops are tuned to the characteristic frequencies of the carrier and produce logical signals to indicate whether the characteristic frequencies are present. If not, a timer is energized to inhibit institution of a loopback condition for the duration of a data burst, after which the phase locked loops are permitted to enable the loopback.

REFERENCES:
patent: 3519935 (1970-07-01), Hochgraf
patent: 3843848 (1974-10-01), Cox
patent: 3952163 (1976-04-01), Couturier et al.

Affiliated with

Also associated with

Rating

Carrier detect and automatic loopback circuit 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 detect and automatic loopback circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Carrier detect and automatic loopback circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-979590