The Performance of Turbo Coded Orthogonal Frequency Division Multiplexing System over Flat Rayleigh Fading Channel


This work investigates the effectiveness of Turbo Codes and Orthogonal Frequency Division Multiplexing (OFDM) system, for communication over the flat Rayleigh fading additive white Gaussian noise (AWGN) channel. The Fast Fourier Transform (FFT) is used in the transmitter and receiver to satisfy the orthogonality between sub-carriers and reduce the implementation complexity. The system performance is investigated for various Doppler frequencies for channel. To reduce the interference at receiver, a guard time with cyclic extension is used. The simulation results show that the turbo code orthogonal frequency division multiplexing (TCOFDM) system achieves large coding gain with lower BER and reduced decoding iterations, where the Turbo code improves the performance of OFDM system by a factor of 5-8 dB, therefore offering higher data rate in wireless mobile communications. الخلاصة