Performance analysis of space-time coded in the MB-OFDM communications system

The emerging ultra wideband (UWB) system offers a great potential for the design of high speed short-range wireless communications. In order to satisfy the growing demand for higher data rates and high capacity, one possible solution is to exploit both spatial and multipath diversities via the use of multiple-input multiple-output (MIMO) and proper coding techniques. In this paper, we proposed two kind of special space time (frequency) coded structure to improve the system performance at MB-OFDM system, space-time block coded MB-OFDM (STBC-MB-OFDM) UWB and space-time-frequency coded MB-OFDM (STFC-MB-OFDM) UWB. Then the STFC-MB-OFDM transmission scheme that we propose in this paper is a simple method with low complexity for improving the performance of conventional STBC-MB-OFDM. The simulation result indicated that, under the revision S-V channel model, the system has increased the channel capacity, STBC-MB-OFDM system may obtain the better diversity gain under the low signal to noise ratio, and STFC-MB-OFDM based on orthogonal preceding is more BER performance than the single antenna system.