A multi-wavelet packet modulation in wireless communications

This paper introduces a multi-wavelet packet modulation (MWPM) which is a multi-band multi-dimensional modulation scheme with a flexible dyadic time-frequency tiling. The proposed MWPM can be considered as a generalization of orthogonal frequency division multiplexing (OFDM) or wavelet packet multiplexing (WPM). Compared to OFDM, the bandwidth efficiency of MWPM is increased r times for the multi-wavelet packets with multiplicity of r. In addition, the effects of frequency-selective wireless channels and high peak to average power ratio (PAPR) in OFDM can be mitigated in the new scheme by properly designing the MWPM dyadic structure. The implementation based on r×r matrix filters for MWPM is also presented in which the fast Mallat algorithm is extended into the vector form. To demonstrate MWPM effectiveness in wireless communication systems, this paper investigates the performance of M-ary QAM signaling combined with MWPM in different sub-bands for the additive white Gaussian noise (AWGN) channel, the slow flat Rayleigh fading channel and the Nakagami-m fading channel. With its advantages, the MWPM is a potential candidate for adaptive implementations in time varying and time dispersive fading channels.