Abstract:

A channel estimation method of high precision in OFDM system, based on least square (LS) algorithm, is proposed. The valid path taps are effectively chosen from the estimation value of channel impulse response (CIR) gotten by LS algorithm, according to the relationship of channel in time domain and then the time domain estimation results are transformed into frequency domain. To utilize the relationship of channel in frequency domain, a linear minimum mean square error (LMMSE) combiner is used to refine the estimation results. The simulation results in the frequency band of 2.4 GHz show that the proposed method achieves a good bit error rate (BER) performance close to the theoretical bound of ideal channel estimation.

Key words: OFDM, channel estimation, channel impulse response