MAP Based Iterative Channel Estimation for OFDM Systems: Approach, Convergence, and Performance Bound

Author

Yinsheng Liu ; Li, Geoffrey Ye ; Hongjie Hu ; Zhenhui Tan

Author_Institution

Inst. of Broadband Wireless Mobile Commun. & State Key Lab. of Rail Traffic Control & Safety, Beijing Jiaotong Univ., Beijing, China

Volume

13

Issue

1

fYear

2014

fDate

Jan-14

Firstpage

476

Lastpage

485

Abstract

Iterative channel estimation (ICE) usually exploits soft information of unknown data symbols as references to improve estimation performance. This paper investigates ICE for orthogonal frequency division multiplexing (OFDM) over wireless channels. The optimum ICE is derived in terms of maximum a posteriori (MAP) criterion, which can be solved using fixed-point iteration (FPI). Furthermore, the derived MAP ICE is closely related to the well-known expectation-maximization (EM) estimation. We also demonstrate that the MAP ICE converges within only one step when the signal-to-noise ratio (SNR) is large through analysis and simulation results.

Keywords

OFDM modulation; channel estimation; expectation-maximisation algorithm; wireless channels; MAP based iterative channel estimation; OFDM systems; estimation performance; expectation-maximization estimation; fixed-point iteration; maximum a posteriori criterion; orthogonal frequency division multiplexing; signal-to-noise ratio; soft information; unknown data symbols; wireless channels; Channel estimation; Convergence; Estimation; Ice; OFDM; Receivers; Vectors; EM algorithm; OFDM; iterative channel estimation; performance bound;

fLanguage

English

Journal_Title

Wireless Communications, IEEE Transactions on

Publisher

ieee

ISSN

1536-1276

Type

jour

DOI

10.1109/TWC.2013.112513.131038

Filename

6678099