Performance analysis of CI/OFDM against nonlinearity of the HPA over multipath Rayleigh fading channel

In this paper, we analyze the performance of orthogonal frequency division multiplexing (OFDM) and carrier interferometry OFDM (CI/OFDM) for high-speed data rate wireless communication systems. For CI/OFDM realization, digital implementation of CI/OFDM structure is used in which CI code spreading and carrier allocation are separately processed by simple inverse fast Fourier transform. Based on previous work, a novel design of these systems is studied for multipath Rayleigh fading channel by using minimum mean square error equalization. The performance of OFDM and CI/OFDM wireless communication systems is compared based on peak to average power ratio, operating distance and bit error rate characteristics over independently additive white Gaussian noise and multipath Rayleigh fading channels. Simulation results show that CI/OFDM system is very useful for high-speed data rate wireless communication system and also provides wider operating range even in the presence of nonlinearity of the high power amplifier.