Wavelet Packet based Multicarrier Modulation for Cognitive UWB Systems

Orthogonal frequency division multiplexing (OFDM) is a multi-carrier modulation(MCM) scheme where the sub carriers are orthogonal waves. The mainadvantages of OFDM are robustness against multi-path fading, frequencyselective fading, narrowband interference, and efficient use of spectrum.Recently it is proved that MCM system optimization can be achieved by applyingwavelet bases instead of conventional fourier bases. Wavelet packet based MCM(WPMCM) systems have overall the same capabilities as OFDM systems withsome improved features. In this research the literature and analytic schemes ofWPMCM system is addressed, a wavelet packet based cognitive ultra wideband(UWB) transceiver is proposed, and performance analysis of WPMCM in differentwireless multipath channels is investigated. Simulation results show a significantenhancement in terms of spectral efficiency, side-lobes suppression and BERcomparing to conventional OFDM.