Blind v.s. training-based UWB timing acquisition with effective multipath capture

This paper provides comparative assessment of effective timing acquisition algorithms for ultra-wideband (UWB) signals transmitting over dense multipath fading channels. First, we propose a new blind acquisition technique with enhanced timing offset estimation accuracy competitive to that of the training approach. To overcome the difficulty for a blind receiver to perform adequate energy capture in dense multipath, we judiciously choose a segment of the received waveform and use it as a noisy correlation-template in frame-rate sampling, followed by cyclostationarity-based blind acquisition. The resulting schemes enjoy large multipath diversity gain without resorting to cumbersome channel estimation, thus improving the acquisition accuracy at a low cost. We then present a comparative study of blind and training-based UWB acquisition methods, all of which are digitally implemented at very low sampling rates. Comparisons in terms of performance, complexity, and system-level impact are evaluated via simulations.