Low complexity partial sampled MMSE channel estimation for downlink OFDMA IEEE 802.16e system

Channel estimation is one of key problems in IEEE 802.16e Orthogonal Frequency Division Multiplexing Access (OFDMA) downlink system. Minimum Mean Square Error (MMSE) channel estimation has been known as a superior performance channel estimation. However, this algorithm has high computational complexity. In this paper, we present low complexity partial-sampled MMSE channel estimation for compromising between complexity and performance. We reduced MMSE channel estimation complexity by partially sampling the MMSE weight matrix. The simulation results show that the bit error rate (BER) performance significantly improved over the least square channel estimation and has comparable BER performance with MMSE channel estimation at low SNR. Depending the sixze of sampling, significant decrease 57 % to 64 % in computational complexity can be achieved.