Digital circuit for determining the envelope frequency of PCM en

Details Digital circuit for determining the envelope frequency of PCM en Digital circuit for determining the envelope frequency of PCM en

1983-08-31

1985-08-06

Safourek, Benedict V.

Pulse or digital communications

Repeaters

Testing

364724, 328134, 34082548, 179 84VF, G06F 1536

Patent

active

045340412

ABSTRACT:
A digital tone detector circuit characterizes the received PCM encoded signals as one of a plurality of call progress tones, voice signals or silence. The PCM signal is linearized and normalized to a predetermined level in a digital automatic gain control circuit which also provides a signal corresponding to the level of the input signal. A first circuit is responsive to the linear signal for providing a count of the zero level traversals incurred by the linear signal. An envelope detector circuit is also responsive to the linear signal for providing a signal representing the envelope frequency thereof. The composite results corresponding to the signal level, the zero-level traversal count, and the envelope frequency are translated in an evaluation logic circuit to provide an output signal representing the identity of the input PCM signal. A microprocessor is responsive to a plurality of the output signals from the evaluation logic circuit for determining the cadence of the received PCM signals.

REFERENCES:
patent: 3961167 (1976-06-01), Mills
patent: 4109109 (1978-08-01), Molleron
patent: 4216463 (1980-08-01), Backof, Jr. et al.
patent: 4302817 (1981-11-01), Labedz
patent: 4354248 (1982-10-01), Conger
patent: 4484354 (1984-11-01), Bennett

Affiliated with

Also associated with

Rating

Digital circuit for determining the envelope frequency of PCM en does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Digital circuit for determining the envelope frequency of PCM en, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Digital circuit for determining the envelope frequency of PCM en will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-516832