Echo protection tone detection and regeneration for digital tran

Details Echo protection tone detection and regeneration for digital tran Echo protection tone detection and regeneration for digital tran

1992-09-18

1993-06-01

Coles, Sr., Edward L.

Facsimile and static presentation processing

Facsimile

Auxiliary signal

358435, 358436, 358438, 358439, 358402, 379406, 370 321, H04N 100

Patent

active

052165191

ABSTRACT:
A transmission arrangement is disclosed which facilitates compression of modem modulated facsimile signals for transmission on digital facilities. The presence of a facsimile call is detected and facsimile control messages are obtained by demodulating and interpreting the facsimile call control protocol. A controller is responsive to the obtained control messages for controlling a voiceband encoder to encode the control portion of the facsimile call and for controlling a so-called facsimile page demodulator to demodulate any facsimile page portions of the facsimile call to obtain a baseband digital bit stream. The presence of prescribed tone signals, i.e., echo protection tone (EPT) signals, is detected in the facsimile call. EPT control messages representative of the EPT signals are generated. The encoded control portion of the facsimile call and the baseband digital bit stream representative of the demodulated, i.e., compressed, facsimile page portion of the facsimile call are transmitted along with control information (as side information) and the EPT control messages to a receiver. At the receiver, a replica of the original modem modulated facsimile signal is reconstructed in response to the control information and by decoding the control portion of the facsimile call and by remodulating the digital bit stream representative of the facsimile page portion of the facsimile call. If EPT control messages are received, the corresponding echo protection tone signal is regenerated for inclusion in the remodulated facsimile signal.

REFERENCES:
patent: 4353095 (1982-10-01), Tatematsu et al.
patent: 4403298 (1983-09-01), May, Jr.
patent: 4519081 (1985-05-01), Sugie
patent: 4885755 (1989-12-01), Yoshida
patent: 5029204 (1991-07-01), Shenoi et al.
patent: 5041917 (1991-08-01), Koshiishi
patent: 5050160 (1991-09-01), Fuda

Affiliated with

Also associated with

Rating

Echo protection tone detection and regeneration for digital tran does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Echo protection tone detection and regeneration for digital tran, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Echo protection tone detection and regeneration for digital tran will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1818872