Sampling Clock Offset Estimation Algorithm Based on IEEE 802.11n

The next generation wireless LAN standard IEEE 802.1 In adopts MIMO-OFDM (multi-input multi-output orthogonal frequency division multiplexing) as a key technology in physical layer. In this paper, the effect of sampling clock offset is analyzed, an algorithm of sampling clock offset estimation is proposed on the system in presence of sampling clock offset. The algorithm is based on the long training field of the preamble, utilizing the correlation between the two same long training symbols. It can perform the sampling clock synchronization efficiently and quickly. The simulation results show that when the SNR (Signal-to-Noise) is 25dB, the MSE (mean square error) of 1IMO (one-input multi-output) system is about 0.5e-4 lower in AWGN channel than in multi-path channel; each receiver antenna is added, the MSE will decline about 0.1e-4; the performance of 2IMO (two-input multi-output) system is worse than HMO system, the MSE is about 0.3e-4 lower.