Performance comparison of RLS and LMS channel estimation techniques with optimum training sequences for MIMO-OFDM systems

Abstract

Channel compensation has been considered as a major problem from the advent of wireless communications, but recent progresses in this realm has made the old problem more challenging. Especially by introducing Space-Time codes and using Array Antennas exploiting an equalization method which can track the changing channel condition with higher accuracy and lower computations is a challenging demand. This paper analyses a suggested new method for channel estimation in a MIMO-OFDM Receiver. In the proposed method, optimum training sequences are derived base on calculated MSE for LS channel estimation, utilizing these training sequences adaptive methods based on LMS and RLS are applied to estimate the channel for a system which emits independent data streams from transmitter antennas. Proposed method is capable of computing all sub-channel coefficients between a receiver antenna and all transmitters. Finally, performances of RLS and LMS algorithms are simulated and compared with LS algorithm.