ICI Self – Cancellation for FFT-OFDM System

Orthogonal frequency division multiplexing (OFDM) is the projected modulation of choice for fourth-generation broadband multimedia wireless systems. OFDM based wireless systems are spectrally efficient but they are vulnerable to Inter carrier interference (ICI). The rapid variation of the channel can induce ICI. ICI will significantly increase the difficulty of OFDM channel estimation. ICI due to carrier frequency offset can be mitigated by accurate frequency synchronization but ICI due to fast fading channel is more difficult to handle. ICI can be easily reduced by increasing the subcarrier spacing. However, a special problem in OFDM is its vulnerability to frequency offset errors due to which the orthogonality is destroyed that result in ICI. ICI causes power leakage among subcarriers thus degrading the system performance it suffers from ICI in the absence of precise frequency synchronization. In this paper, the OFDM system is modeled and simulated under AWGN channel. The interesting with combating the effects of ICI induced by carrier frequency offsets (CFO), where presented the ICI Self- Cancellation Scheme algorithm to combat ICI effect