Design of Video NLOS Communication System Using MIMO-OFDM Based on IEEE802.16a Standard

Rapid development in the area of broadband wireless communications demands wireless video services. The maximal challenges of transmitting video over wireless channels are non-line-of-sight (NLOS) fading deteriorate and higher data rates requirement. Fortunately, the 802.16a standard supports licensed and license-exempt spectra between 2 and 11 GHz, which is especially useful for NLOS cases. On the other hand, multiple-input multiple-output (MIMO) systems provide higher capacity, higher data rates and lower error rate than standard single-input single-output (SISO) systems. So in order to solve the problem of video signal transmission on NLOS wireless channels, this paper presents the design of MIMO-OFDM system based on IEEE 802.16a standard. By using Alamouti´s ST block code (STBC) transmission diversity at transmit antennas and (maximum ratio combing) MRC diversity at receive antennas, high data rates can be gotten. Experiment results showed that our proposed system can achieve very good performance, and the system with more antennas got a significant PSNR improvement over none diversity situation