Performance Enhancement of STBC-OFDM from CIOD with Interference Cancellation over Time-Varying Channels

Space-time block coded orthogonal frequency division multiplexing (STBC-OFDM) from coordinate interleaved orthogonal design (CIOD) is considered to be an effective space- time code (STC) to achieve full-rate and full-diversity with a simple maximum-likelihood (SML) decoder. However, the SML decoder cannot prevent the performance degradation completely due to time-varying effects such as co-channel interference (CCI). In this paper, we propose a decoding scheme to reduce the CCI after comparing the performance of the various STCs in time-varying environment. To fully exploit the special characteristic of the CIOD, the proposed decoding scheme consists of two stages: two symbols are decoded in advance and then used for decoding of the rest symbols in the form of interference cancellation. Simulation results demonstrate that the proposed receiver achieves significantly enhanced performance over time-varying channel compared to that of the SML. The complexity analysis of the proposed scheme and the conventional decoding schemes is also delivered.