Synchronization-Free Data Detection for UWB Communications

The dense multipath scattering typical of ultra-wideband (UWB) wireless channels provides very large multipath diversity, but from the other side makes the receiver design a demanding task as far as channel estimation and timing recovery are concerned. The contribution of this paper is to derive a novel receiver structure based on the multiple symbols differential detection (MSDD) framework with particular emphasis on bypassing costly channel estimation and relaxing the stringent requirements imposed on timing recovery. The computational complexity of the proposed detection scheme, that becomes quite impractical as the data block size increases, is then circumvented by resorting to an efficient implementation based on the sphere decoding (SD) algorithm. Simulation results carried out in typical multipath propagation scenarios verify that appealing detection performance is achieved at affordable receiver complexity.