BER Performance of Clipped and Filtered OFDM/TDM with Pilot-assisted Channel Estimation

Abstract: Orthogonal frequency division multiplexing combined with time division multiplexing (OFDM/TDM) was proposed to overcome the high peak-to-average-power ratio (PAPR) of conventional OFDM. Clipping and filtering can be used to further reduce the PAPR. OFDM/TDM with minimum mean square error (MMSE) frequency-domain equalization (FDE) requires accurate channel estimation (CE). In this paper, pilot-assisted CE with frequency-domain interpolation for clipped and filtered OFDM/TDM with MMSE-FDE is presented. We consider frequency-domain polynomial (i.e., linear and second-order) and delay time-domain interpolation techniques. In the frequency-selective fading channel, frequency-domain linear and second-order polynomial interpolation gives poor performance while good performance is obtained with delay time-domain interpolation. It is shown that as the channel frequency-selectivity increases, OFDM/TDM with MMSE-FDE can obtain larger frequency diversity gain and improve the bit error rate (BER) performance.