关键词: 通信技术, 半盲信道估计, OFDM系统, LMMSE, SVD, 非均匀间隔导频

Abstract: In order to overcome the disadvantages of system performance degradation on the condition of pilot numbers smaller than channel impulse length and bad channel environment in many paths, an improved semiblind channel estimation algorithm based on MLE for OFDM system was presented. The proposed algorithm can reach small system mean square error with nonuninformed pilots. And by the reduction of pilot numbers, frequency resource of the system is increased. In addition, with singular value decomposition, the algorithm computational complexity can be simplified. It is known from the simulation results that when full use of channel statistical information, under the condition of small number pilots, long channel impulses and low SNR, the proposed algorithm can achieve better channel estimation with lower computational complexity, which proves the effectiveness and advantage of the algorithm.

Key words: communication, semiblind channel estimation, OFDM system, LMMSE, SVD, nonuniform space pilots