Premium
Amplitude‐phase constraints based blind and semi‐blind channel estimation for OFDM systems
Author(s) -
Chen Wei,
Liu Guanghui,
Zhu Weile
Publication year - 2012
Publication title -
transactions on emerging telecommunications technologies
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.366
H-Index - 47
ISSN - 2161-3915
DOI - 10.1002/ett.2525
Subject(s) - orthogonal frequency division multiplexing , estimator , channel (broadcasting) , algorithm , blind equalization , amplitude , phase (matter) , computer science , mathematics , phase shift keying , control theory (sociology) , telecommunications , statistics , bit error rate , equalization (audio) , artificial intelligence , physics , chemistry , organic chemistry , control (management) , quantum mechanics
In this paper, a new blind channel estimation method for orthogonal frequency division multiplexing systems is presented. The proposed approach based on the amplitude‐phase constraints of the channel frequency response first estimates the channel amplitude‐frequency response, and then calculates the channel‐frequency response of the equivalent minimum phase system by its amplitude‐frequency response. The zeros of the actual system and its equivalent minimum phase system are symmetric about the unit circle, and the symmetric relationships are easily determined according to the finite alphabet property of information symbols. A semi‐blind estimation method based on the blind estimation method is also proposed in this paper, and it greatly reduces the numerical complexity of the blind method. Unlike existing statistical blind channel estimators, the proposed method requires short data records especially for phase‐shift keying modulation. Compared with the existing finite alphabet based method, the proposed method has a lower numerical complexity. Comparison of the proposed method with training based estimation method, which is presented by computer simulations, show the effectiveness of the proposed method. Copyright © 2012 John Wiley & Sons, Ltd.