Enhanced FCME Thresholding for Wavelet-Based Cognitive UWB Over Fading Channels
The cognitive Ultra-WideBand (UWB) network detects interfering narrowband systems and adapts its configuration accordingly. An inherently adaptive and flexible candidate for cognitive UWB transmission is the Wavelet Packet Multi-Carrier Modulation (WPMCM). In this paper, the authors use an enhanced forward consecutive mean excision thresholding algorithm to tackle the noise uncertainty in the wavelet-based sensing of WPMCM systems, and mathematical analysis is performed for primary user channel fading. As a benchmark, they compare the proposed system with a conventional fast Fourier transformation-based system, and performance investigation proves significant improvements when primary and secondary links are subjected to multipath fading and noise.