Patent · US Expired

Apparatus and methods for coding, decoding, analyzing and synthesizing a signal

US4672670A · kind A · utility

67Cited by
3References
43Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 26, 1983
Grant dateJun 9, 1987
Priority date
Expiry dateJul 26, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG10L25/27
  • WIPO fieldTelecommunications
  • WIPO sectorElectrical engineering

Abstract

In an ADPCM (Adaptive Differential PCM) system, in which the signal is commonly coded in C.sub.i, Q.sub.n, and .sigma. parameters, a lower sampling rate which normally causes distortion is made possible by deriving additional parameters A.sub.k, B.sub.k as a function of the error (distortion) between the original signal S.sub.n and the sampled signal Y.sub.n. The A.sub.k, B.sub.k coefficients control a distortion filter at the receiver.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.