Pulse or digital communications – Pulse code modulation
Patent
1994-10-07
1998-04-07
Bocure, Tesfaldet
Pulse or digital communications
Pulse code modulation
375240, H04B 1404, H04B 166
Patent
active
057373671
ABSTRACT:
An audio signal digital transmission system wherein the signal is sampled and successive segments each of N samples are digitally encoded. Encoding has heretofore been effected by vector quantization, whereby a memory stores a book of a large number of codewords corresponding to possible segments of successive signal samples, and the best matching stored segment is determined by calculation. The present invention bases encoding on comparison of the envelope of a signal segment with a limited number of reference envelopes. The best matching reference envelope is selected, and an identifying codeword therefore is transmitted along with related parameters. A receiver reproduces the signal from the reference envelope and the related parameters. Since identified envelopes of the signal segments are less variable and simpler to evaluate than the signal samples in the segments, a considerable reduction of memory capacity and calculation complexity is achieved.
REFERENCES:
patent: 3621397 (1971-11-01), Murotani
patent: 3715512 (1973-02-01), Kelly
patent: 4216354 (1980-08-01), Esteban et al.
patent: 4569075 (1986-02-01), Nussbaumer
patent: 4677671 (1987-06-01), Galand et al.
patent: 4979188 (1990-12-01), Kotzin et al.
patent: 5150387 (1992-09-01), Yoshikawa et al.
patent: 5384793 (1995-01-01), Zinser
patent: 5490170 (1996-02-01), Akagiri et al.
CITT Recommendation G. 728 "Coding of speech at 16 kbit/x using low delay code excited linear prediction".
"Bit Rates in Audio Source Coding" by R.N.J. Veldhuis in IEEE Journal on Selected Areas in Communications, vol. 10, No. 1, Jan. 1992.
"Predictive Coding of Speech at Low Bit Rates" by B.S. Atal in IEEE Transactions on Communications, vol. COM-30, No. 4, Apr. 1984.
"Information technology--Coding of moving pictures and associated audio for digital storage media up to about 1.5 Mbit/s", section 3, pp. 174-337.
De Bont Franciscus M. J.
Wuppermann Friedhelm
Bocure Tesfaldet
Eason Leroy
U.S. Philips Corporation
LandOfFree
Transmission system with simplified source coding does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Transmission system with simplified source coding, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Transmission system with simplified source coding will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-20679