This paper proposes a dual-tree complex wavelet transform (DTCWT) based adaptive rake receiver for Ultra-Wideband (UWB) systems. Advantage of using dual tree complex wavelet transform is that instead of capturing the signal energy in different multipath components at different delays, it captures them at different frequency components. LMS equalizer used in the receiver structure reduces the ISI. This adaptive scheme does not require all the parameters of the multipath components, but a short training period is only required to adjust the tap weights. The performance of the proposed receiver is evaluated and compared with existing conventional adaptive rake receiver and adaptive continuous wavelet transform rake receiver. All possible rake combinations such as ARAKE, SRAKE and PRAKE are considered, and it is found that the performance of the proposed system has shown a significant SNR improvement of 5-6 dB over conventional adaptive rake receiver.
UWB system, Rake receiver, Wavelet transform, DTCWT
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