Channel Equalization in Wavelet Packet Modulation by Minimization of Peak Distortion

Wavelet Packet Modulation (WPM) is a multicarrier modulation technique like the well-established Orthogonal Frequency Division Multiplexing (OFDM). The channel equalization of WPM is important and unique due to the symbol overlap in time. In this article we present a time-domain equalizer for the compensation of channel induced distortions on the WPM transmission. The equalizer applies the principle of peak distortion criterion where the maximum inter-symbol interference caused by the channel is minimized. The operation of the equalizer is tested under different realistic channels with different taps and characteristics. Furthermore, investigations to understand the impact of the wavelet family, length of the wavelet filters, and the number of equalizer taps on the performance of the equalizer are carried out. The operation of the proposed algorithm is demonstrated through numerical simulations. Results of the simulation studies illustrate notable performance gains including better Bit Error Rate (BER) performance and lower Inter symbol interference (ISI).