An oversampled channelized UWB receiver with transmitted reference modulation

摘要

To digitize the ultra-wideband (UWB) signal at its Nyquist rate, a frequency channelized receiver for UWB radio based on hybrid filter banks (HFB) is presented. Among the challenges of such receivers are the uncertainties of the analog analysis filters and the slow convergence speed. To overcome these problems, a channelized receiver operating at slightly above the critically sampling rate is presented. The proposed receiver, which is designed for use in transmitted reference (TR) systems, combines the synthesis filters and the matched filter so that the joint response of the analysis filter and the propagation channel can be estimated independently in each subband. When the input noise is colored or a narrowband interference (NBI) is present, the weighting in each subband can be adaptively adjusted so to approximate the noise whitening and matched filtering operation for near optimal detection. The adaptive performance of the proposed receiver is slightly better than an ideal full-band receiver when the input noise is white and significantly better when a NBI is present. The effect of the automatic gain controller (AGC) and the analog-to-digital converter (ADC) are also considered. The proposed receiver with 3-bit ADC seems sufficient to achieve performance comparable to an infinite bit channelized receiver even in the presence of large NBI.