In this paper, the performance of Asymmetrically Clipped Optical Wavelet based Orthogonal Frequency Division Multiplexing (ACO WOFDM) system is compared to the performance of Asymmetrically Clipped Optical Orthogonal Frequency Division Multiplexing (ACO OFDM) system. Then a Coded ACO WOFDM (CACO WOFDM) communication system over a multimode optical channel is investigated. The used wavelet transform is the Wavelet Packet Transform (WPT). Quadrature Amplitude Modulation (QAM) is used as the modulation format. The simulation results show a considerable performance improvement of ACO WOFDM system in terms of BER and slight performance improvement of ACO WOFDM system in terms of OSNR Compared to the ACO OFDM system. Also, from the simulation results, we find that the CACO WOFDM considerably improves the BER and OSNR performance of the communication system.