Frame synchronization at the sound of silence

A novel approach is introduced for the design of the unique word (UW) to be inserted into TDM/TDMA systems for frame synchronization purposes. In particular, the UW is composed by all zero symbols that are distributed along the frame in order to improve the autocorrelation properties. The resulting UW is identified as silent-UW (S-UW). We show in this paper that S-UW leads to an optimum detector with very limited complexity, and with performance that can be significantly better than the classic UW in the presence of frequency offsets or at moderate to high signal-to-noise ratios. A fully analytical performance characterization is presented reporting also comparisons with state-of-the-art alternatives.