Error reduction due to carrier frequency offset in OFDM system using turbo codes

Orthogonal Frequency Division Multiplexing (OFDM) has been suggested and standardized for highspeed communications because of its ability to mitigate frequency dependent distortion across the channel bandwidth. One of the most important drawbacks of OFDM that it is very sensitive to inaccurate frequency references. A carrier offset at the receiver can cause losses in sub carrier orthogonality, introducing inter carrier interference (ICI) degrading the system performance. In this paper, coded OFDM is used to decrease the effect of carrier frequency offsett on OFDM system performance. The simulated TCOFDM was tested under fading AWGN channel, The simulation results show that the TCOFDM system achieves large coding gain with lower BER and reduced decoding iterations, therefore offering higher data rate in wireless mobile communications and also increasing the frequency offset range allowing for higher mobility.