Patent · US Expired

Efficient methods for filtering to avoid inter-symbol interference and processing digital signals having large frequency guard bands

US7113559B2 · kind B2 · utility

20Cited by
5References
52Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 24, 2001
Grant dateSep 26, 2006
Priority date
Expiry dateJan 25, 2024

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2025/03414
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A circular filtering system that prevents the problem of inter-symbol interference. The circular filtering system utilizes a buffer memory to store samples of a given symbol and provide only these samples to a linear filter such that the output of the filter, for any given symbol is formed by filtering only samples of that input symbol. Each symbol being filtered independent of other symbols hence eliminating inter-symbol interference caused by filtering. Where symbols are tolerant to a fixed phase shift for each symbol, the circular filtering system can be simplified by reducing the size of the buffer and introducing a multiplexer.

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