Performance improvement of wavelet packet transform over fast Fourier transform in multiple-input multiple-output orthogonal frequency division multiplexing systems
This study presents a proper way to improve the multiple-input multiple-output orthogonal frequency division multiplexing (OFDM) system by proposing a new tackling method to reduce the peak-to-average power ratio (PAPR). It is attained by reconstructing the fast Fourier transform block in the OFDM based on the wavelet packet transform, called forward wavelet frequency division multiplexing. In addition, a new pre-processing technique has been introduced to increase the orthogonality among the tested data which is based on imposing the eigenvalues/eigenvector extracting features. Numerical and simulation results show that the combination between the new structure of OFDM transceivers and the pre-processing block has lower PAPR values. It is compared with the conventional OFDM structures and showed that the bit error rate performance has been improved for the same bandwidth occupancy, which is attained at the cost of introducing additional complexity to the transceiver's structure. The simulation results show that 6–60% reduction in PAPR over current values in the literature can be achieved depending on the system type.