Synchronization in MB-OFDM-based UWB Systems

This paper presents a preamble-based low complexity synchronization method for MB-OFDM based UWB systems. The proposed synchronization method consists of sync detection, coarse timing estimation, fine timing estimation, and oscillator frequency offset estimation. The distinctive features of MB-OFDM systems and the interplay between the timing and carrier frequency hopping at the receiver are judiciously incorporated in the proposed synchronization method. We also derive the probability density functions (pdfs) of the delays of the UWB channel paths which are used in optimizing our synchronization method. These pdfs are also useful in evaluating or optimizing the energy capture of other UWB systems. The effectiveness of our proposed synchronization method and optimization criteria are confirmed by computer simulation results.

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