Patent · US Expired

Decision feedback channel estimation and pilot tracking for OFDM systems

US7039004B2 · kind B2 · utility

38Cited by
16References
24Claims
0Family size

Assignee

Inventors

Key dates

Filing dateOct 1, 2002
Grant dateMay 2, 2006
Priority date
Expiry dateMar 24, 2023

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L2025/03522
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Current OFDM systems use a limited number of symbols and/or sub-channels to provide approximations for channel estimations and pilot tracking, i.e. phase estimations. For example, two training symbols in the preamble of a data packet are used to provide channel estimation. Four of the fifty-four sub-channels are reserved for providing phase estimation. However, noise and other imperfections can cause errors in both of these estimations, thereby degrading system performance. Advantageously, decision feedback mechanisms can be provided to significantly improve channel estimation and pilot tracking in OFDM systems. The decision feedback mechanisms can use data symbols in the data packet to improve channel estimation as well as data sub-channels to improve pilot tracking.

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