Adaptive prediction differential PCM-type transmission apparatus and process with shaping of the quantization noise
US4385393A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 10, 1981 |
| Grant date | May 24, 1983 |
| Priority date | — |
| Expiry date | Apr 10, 2001 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M3/042
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
A coding process for the adaptive prediction differential PCM type. An error signal e.sub.t is formed between a sample of signal y.sub.t to be coded and a prediction signal p.sub.t of said signal. The prediction signal p.sub.t is formed from restored signals y.sub.t and e.sub.t by two linear filtering operations, the first relating to N successive samples of y.sub.t and using coefficients A1.sub.t, A2.sub.t, . . . , AN.sub.t and the second relating to P successive samples of e.sub.t and using coefficients B1.sub.t, B2.sub.t, . . . , BP.sub.t, the coefficients A1.sub.t, A2.sub.t, . . . , AN.sub.t and B1.sub.t, B2.sub.t, . . . , BP.sub.t being sequentially adjusted at each time t so that the mean power of error signal e.sub.t is minimal. Instead of carrying out the prediction on the basis of signals y.sub.t and e.sub.t only according to the invention, use is also made of the real signal y.sub.t and the real error e.sub.t. A linear filtering of y.sub.t using the coefficients A1.sub.t, A2.sub.t, . . . , AN.sub.t, these coefficients affecting N successive samples of the signal y.sub.t, a linear filtering of e.sub.t using the coefficients B1.sub.t, B2.sub.t, . . . , BP.sub.t are performe…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.