A Universal MMSE-DFE Equalizer with its Application to WLAN Receiver

Time-domain equalizer (Proakis in Digital communications, McGraw-Hill, New York, 2001) is one of most promising approaches to combat the interference caused by the mulitpath effect, and important for many applications in the wireless communication. We therefore investigate a simple universal time-domain minimum mean square error-decision feedback equalizer with a simple adaptive channel estimator to approach the near-optimal performance for mobile users. Furthermore, the method can be readily extended to the receivers incorporating with time-domain equalizers in other wireless communication scenarios such as OFDM systems over doubly selective channels. Using the Givens rotation based Cholesky factorization, the optimum feedforward and feedback coefficients can be easily derived with very low complexity. The simulation results demonstrate that the proposed method can approach the near-optimum performance using LMS channel estimation, and is suitable for the mobile terminals.