Performance of turbo coded OFDM system with comb pilot channel estimation in Rayleigh fading channel

Orthogonal frequency division multiplexing (OFDM) combines the advantage of high achievable rates and relatively easy implementation. In this paper we investigate the combined use of the turbo codes (TC) and the orthogonal frequency division multiplexing in Rayleigh fading channel. The comb-type pilot arrangement with the LS estimator and 1D interpolation are used for channel estimation. The system is called TC-QPSK-OFDM with comb pilot channel estimation. The simulation results of TC-QPSK-OFDM show that three iterations are sufficient to provide good BER performance. Coding gains of 7.5 dB at BER 5*10^-5 in AWGN channel and 5 dB at 10^-5 in Rayleigh Fading channel are achieved.