Low-Complexity Blind Equalization for OFDM Systems With General Constellations
Tareq Y. Al-Naffouri, Ala A. Dahman, Muhammad Saqib Sohail, Weiyu Xu, Babak Hassibi · IEEE Transactions on Signal Processing · 2012
This paper proposes a low-complexity algorithm for blind equalization of data in orthogonal frequency division multiplexing (OFDM)-based wireless systems with general constellations. The proposed algorithm is able to recover the transmitted data even when the channel changes on a symbol-by-symbol basis, making it suitable for fast fading channels. The proposed algorithm does not require any statistical information about the channel and thus does not suffer from latency normally associated with blind methods. The paper demonstrates how to reduce the complexity of the algorithm, which becomes especially low at high signal-to-noise ratio (SNR). Specifically, it is shown that in the high SNR regime, the number of operations is of the orderO(LN), whereLis the cyclic prefix length andNis the total number of subcarriers. Simulation results confirm the favorable performance of the proposed algorithm.