Performance of space-time block coding and space-time trellis coding for impulse radio

Ultra Wide Band (UWB) systems have attracted a lot of research interest lately, owing to their appealing features in short-range mobile communications. These features include low power peer-to-peer transmissions, multiple access communications, high data rates, and precise positioning capabilities. Space-Time Coding (STC) techniques, such as the block coding scheme, or the trellis coding scheme, are known to be simple and practical ways to increase the spectral efficiency in wireless communications. In this paper, we aim to combine Pulse Position Modulation (PPM) - Impulse Radio Multiple Access (IRMA) system with two different space-time coding techniques. Thus, we developed a space-time block codes and adapted a space-time trellis codes scheme to UWB signalling, relying on the Channel State Information (CSI) at the receiver side. Then the added diversity produces by these techniques is exploited to enhance the performance of UWB systems. Analysis is conducted in a typical UWB environment, with Fractionally-Spaced (FS) coherent Rake detection.