基于MM算法的稀疏无线信道估计

Orthogonal Frequency-Division Multiplexing (OFDM) is a key technique of modern wireless communication system. The performance of OFDM is greatly impacted by the Inter-Carrier Interference (ICI). To eliminate the impact caused by ICI, estimation of Channel Impulse Response (CIR) is crucial. In this paper, a Majorization-Minimization （MM）algorithm based channel estimation method for OFDM system is proposed. By exploiting the intrinsic sparsity of wireless channel in delay-Doppler shift domain, sparse representation of wireless channel for OFDM system is obtained. MM algorithm based sparse signal recovery method is used to estimate this sparse representation. Estimation of original wireless channel is further obtained. Compared with conventional method, the proposed MM-based sparse channel estimation method promotes stronger sparsity to improve performance of wireless channel estimation. The simulation results show that the proposed method yields more accurate wireless channel estimation for OFDM system with smaller pilots overhead.