Removal of cyclic prefix in Adaptive Non-Contiguous OFDM for Dynamic Spectrum Access using DWT and WT
نویسنده
چکیده
Spectrum has valuable resource in wireless communication. In wireless communication some spectrum is waste due to uses of cyclic prefix (cp) in FFT multicarrier sampling. In place of FFT used DFT and wavelet transform function for removal of cyclic prefix. Wavelet based OFDM, particularly using DWT and WPT-OFDM as situations for Fourierbased OFDM with the focus on impulse noise effects. We begin by constructing the models of the inverse and forward transforms. We explain in detail each model and study the BER performance in two scenarios when varying the Poisson recurrence parameter a from small to large. The wavelet based SOFDM (DWT-SOFDM and WPT-SOFDM) are assumed to have other normal bases and perfect reconstruction properties. Results show that a large values of limits the impact of impulsive noise on the system. We also found that the WPT-SOFDM platform is superior in BER to others.
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