Chi-Square Distribution-Based Confidence Measure Channel Estimation Method in OFDM Systems

Abstract

ABSTRACTThere are many channel estimation algorithms for orthogonal frequency division multiplexing (OFDM) system. However, most algorithms cannot suppress the noise effectively, which affects the quality of the final received signal. During wireless channel estimation, the noise has negative impact on channel estimation result. To reduce channel estimation errors, it is necessary to suppress the noise of the channel. In confidence measure (CM) channel estimation, the sampling points are distinguished into multipath and noise, and then the noise is suppressed based on the confidence. However, the performance of CM channel estimation method is not better than that of conventional methods in dynamic channels. Furthermore, to reduce the false alarms effectively, this paper proposes Chi-square distribution-based CM channel estimation method in cyclic prefix OFDM (CP-OFDM) system. Performance comparison is shown to verify the effectiveness of the proposed Chi-square distribution-based CM channel estimation method in multipath propagation conditions.