Optimum frequency-domain partial response encoding in OFDM system

Time variance of wireless channels destroys the orthogonality among subchannels in orthogonal frequency-division multiplexing (OFDM) systems and causes interchannel interference (ICI), which results in an error floor. In this paper, we study frequencydomain partial-response coding (PRC) for reducing the effect of the ICI. Based on the general expression of the ICI power for OFDM with PRC, the optimum weights for PRC that minimize the ICI power are derived. From the numerical and simulation results, optimum PRC for OFDM can reduce the ICI effectively by 4.0 dB for two-tap PRC and 6.2 dB for three-tap PRC, respectively.