Better wavelet packet tree structures for PAPR reduction in WOFDM systems

This paper presents a proper way to reduce the peak-to-average power ratio (PAPR) in Daubechies (Db) wavelet-based OFDM (WOFDM) by searching better wavelet packet tree (BWPT) structures. These BWPT structures are obtained by using a brute force search algorithm. Numerical and simulation results also show that BWPT structures have lower PAPR values than conventional Mallat structures without any degradation in bit error rate (BER) performance for the same bandwidth occupancy. In addition, this PAPR reduction method does not introduce any additional complexity to WOFDM system since BWPT structures are obtained by selecting the proper ones from wavelet packet tree space.