摘要

We propose a new approach for timing synchronization estimation with polarity comparison for multi-band orthogonal frequency division multiplexing (MB-OFDM)-based UWB systems. We attempt to locate the start sample of frame sequences by calculating difference of the two cross-correlation functions, between received symbols, the successive received symbols, and predefined preamble sequence. It makes sense to propose polarity comparison and identification ideas to the scenario, the cross-correlation difference exceeding predefined threshold is not unique. If polarities of selected symbols are not all the same, the estimator is put forward to find out a peak of correlation summation to figure out the unique timing point and promote synchronization accuracy. Uniqueness and accuracy of timing synchronization, therefore, could be guaranteed. The performance of the proposed estimator is evaluated by mean square error (MSE) and synchronization probability. The proposed estimator could carry out timing synchronization for MB-OFDM-based UWB systems and make the uniqueness of timing index for sure. The MSEs of the proposed estimator are evidently lower than the reference method for a great deal. Total and exact synchronization probability could get as much as 100 and 96%.

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