Method and apparatus for equalization for transmission over a band-limited channel
US5412691A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 15, 1994 |
| Grant date | May 2, 1995 |
| Priority date | — |
| Expiry date | Jun 15, 2014 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/03834
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A technique for compensating for frequency distortion in a band-limited communication channel, using a random-access memory (RAM) to store successive samples of a signal pulse, the samples having been precalculated to perform an equalization function prior to transmission of the pulse. The signal samples are retrieved, converted to analog form, and filtered to produce a precompensated analog pulse signal. In one embodiment of the invention, equalized profiles of a limited number of pulses of different shapes are stored in the RAM, and are retrieved as needed for transmittal through the band-limited channel. Thus the invention can perform its equalization function while facilitating encoding of the signal into a different form, such as modified duobinary code.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.