Improved cyclic prefix reconstruction and its application to space-time block coded orthogonal frequency division multiplexing transmission

In this paper, we describe a new technique to restore the cyclicity of the received signal when the cyclic prefix (CP) is not sufficient for OFDM systems. The proposed technique efficiently restores the cyclicity of the ith received symbol by adding the weighted (i + 1)th received symbol to the ith received symbol. The iterative CP reconstruction (CPR) procedure is obtained using the proposed technique and the residual intersymbol interference cancellation (RISIC) algorithm. In addition, we apply the CPR method to the Alamouti space-time block coded (STBC) OFDM system. It is shown that in the STBC OFDM, tail cancellation as well as cyclic reconstruction of the CPR procedure should be repeated. Simulation results show that the proposed CPR algorithm outperforms the conventional RISIC in the symbol error rate even when the channel impulse response is longer than a half of the symbol duration, for multiple antenna applications.