Patent · US Expired

Adaptive equalizer capable of linear and nonlinear weighting

US4435823A · kind A · utility

33Cited by
11References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateDec 29, 1980
Grant dateMar 6, 1984
Priority date
Expiry dateDec 29, 2000

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L25/03057
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Equalizers are commonly used in digital data signaling systems to reduce the effects of intersymbol interference on a signal received over a transmission channel. However, conventional equalizers are relatively slow due to their use of multipliers. Also, generally such equalizers are limited to providing a linear response to the received input signal samples. Accordingly, to provide a high-speed equalizer which is capable of both linear and nonlinear response, a transmission channel signal containing intersymbol interference is passed through a delay means which provides sequential Q-bit samples of said transmission channel signal. These Q-bit samples are then applied to a weighting means which includes a memory having stored equalizing weighting values which are accessed in accordance with the Q-bit samples to provide predetermined weighted output words in response to the Q-bit samples. These output words can be either linear or nonlinear with respect to the Q-bit samples. This technique serves to reduce intersymbol interference in the received signal thereby equalizing this signal. Also, since no multipliers are necessary, the equalizing operation can be carried out at a very hig…

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