Space-Frequency Codes for Multiband UWB Communication Systems

This paper proposes a SF coding scheme that can achieve rate-M_t pcu in MIMO-multiband UWB system. This code is constructed based on the principle of unitary matrix precoder so that information symbols are spread across adjacent subcarriers, allowing effective exploitation of frequency diversity. By using maximum likelihood decoder, the performance of this SF code for two transmit antennas over the IEEE 802.15.SG3a channel models is shown to outperform well known repetition codes and full rate SF codes, which guarantee full diversity. In addition, we devise a random interleaving to incorporate into the proposed code and the simulation results show that further gains can be achieved depending on the level of SNR. All SF codes examined appear to perform well under extreme NLOS multipath channel as compared to LOS lower delay spread channel