Multiplex communications – Wide area network – Packet switching
Patent
1979-12-28
1981-10-13
Olms, Douglas W.
Multiplex communications
Wide area network
Packet switching
370 79, 370104, H04J 316
Patent
active
042952174
ABSTRACT:
In reconstructing the analog waveform from a syllabically companded delta modulated digital signal transmitted over a TDMA communication channel operating at near its maximum channel capacity, the noise created in a mid-talkspurt freeze-out is greatly reduced by interpolating the amplitude of the waveform during the freeze-out at the receiver as that of the waveform in the previous period. This makes the quality of voice transmissions in the face of freeze-outs substantially better than prior art techniques which induce background noise during freeze-outs, without the necessity of transmitting a voice activity compression (VAC) mask to control the operation of the interpolation apparatus in the receiver. The interpolation occurs for the first 15 msec sampling period following either a freeze-out or a true VAC operation. The interpolation operation is supplied only once so that if two or more consecutive sampling periods occur at the receiver where no channels are received for a particular voice port, the background noise is injected into the voice port. This prevents the uncontrolled repetition of the interpolation at the end of a talkspurt.
REFERENCES:
patent: 3927268 (1975-12-01), Sciulli et al.
patent: 3975686 (1976-08-01), Appel
patent: 4005276 (1977-01-01), Abramson et al.
Fennel, Jr. John W.
Hallett Robert J.
Head Stanley M.
Melas Constantine M.
IBM Corporation
Klitzman M. H.
Olms Douglas W.
LandOfFree
Apparatus to reduce the effect of a mid-talkspurt freeze-out does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Apparatus to reduce the effect of a mid-talkspurt freeze-out, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Apparatus to reduce the effect of a mid-talkspurt freeze-out will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-934706