Multiple symbol differential detection for UWB communications

Multiple symbol differential detection (MSDD) offers high-performance symbol recovery and bypasses training or channel estimation, which are highly desired features in low- power ultra-wideband (UWB) communications. However, UWB impulse radios entail distinct signaling structures and stringent performance-complexity requirements, giving rise to the need for a new MSDD scheme capable of coping with dense multipath UWB channels and detecting a large block of symbols at practical complexity. To this end, this paper develops a novel MSDD-based UWB receiver that attains the desired performance advantages by jointly detecting blocks of received symbols based on the autocorrelation principle. To enable practical implementations at desired performance versus complexity tradeoffs, new optimization formulations are introduced to derive fast implementation algorithms inspired by powerful signal processing tools including sphere decoding and Viterbi algorithm, in both soft- and hard-decision versions. Extensive simulations testify the realistic performance of the proposed detectors in the presence of multiple access interference, timing synchronization errors and low-resolution digital-to-analog conversion.