Patent · US Expired

Preamble design for frequency offset estimation and channel equalization in burst OFDM transmission system

US7554902B2 · kind B2 · utility

25Cited by
10References
34Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 23, 2003
Grant dateJun 30, 2009
Priority date
Expiry dateDec 7, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04L27/2675
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

Provided is a transmission data frame in an orthogonal frequency division multiplexing (OFDM) burst mode transmission, and more particularly, a frequency offset estimating method and a channel equalizing method using a transmission data frame. In the transmission data frame used in the orthogonal frequency division multiplexing burst mode transmission, a length of a guard interval in a preamble area for frequency offset estimation and channel estimation varies depending on a channel environment not being limited in consideration of a size of a data symbol, and only data of ending part of the guard interval in the preamble is used to estimate frequency offset in consideration of intersymbol interference. In the frequency offset estimating method, desired frequency estimation efficiency can be satisfied with the small number of samples. Also, when channel equalization is performed, two symbols are averaged in a time area to reduce the accuracy of channel estimation due to Gaussian random noise. In a frequency area, by referring to weight placed on an adjacent subcarrier, a channel equalization coefficient is obtained to efficiently reduce Gaussian random noise.

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