Space-time coding options for OFDM-based WLANs

Space-time block codes and space-time trellis codes have recently been introduced to improve the performance of wireless systems. In this paper, we reconsider first the design criteria for space-time trellis codes in our context of application that is OFDM-based WLAN. We show by simulations that the rapid Rayleigh fast fading criteria are appropriate and we propose a code optimized accordingly. Then, we compare space-time block coding solutions with trellis-based ones, both including convolutional coding and interleaving. For that purpose, we also designed and simulated a rate 1/2 space-time trellis code, in which the channel and space-time coding are jointly optimized.