Efficient Implementation of Robust OFDM Channel Estimation

In this paper an efficient implementation of robust pilot-symbol aided channel estimation (PACE) for OFDM is presented. We propose to cyclically delay the received signal after removal of the cyclic prefix. The purpose of the cyclic delay is to match the received signal after OFDM demodulation to a channel estimation filter with real valued coefficients. Compared to the conventional approach which requires complex valued coefficients, the computational cost is cut by half, without any degradation in performance. Moreover, the impact of a timing synchronization unit on the considered channel estimation filter is examined