Performance analysis of Alamouti STBC MIMO OFDM for different transceiver system

Multiple-input, multiple-output orthogonal frequency-division multiplexing (MIMO-OFDM) is the dominant air interface for 4G and 5G broadband wireless communications. It combines MIMO technology, which multiplies capacity by transmitting different signals over multiple antennas, and OFDM which divides a radio channel into a large number of closely spaced sub-channels to provide more reliable communications at high speeds. Nevertheless, MIMO system experiences the inter-symbol interference (ISI) effects particularly in high data rate transmissions in which the system performance is extremely degraded. Thus far, Space Time Block coded (STBC) orthogonal frequency division multiplexing is a most reliable technique to attain bandwidth efficiency and ISI suppression ability. In our present work, the performance of different adaptive modulation scheme is analyzed. Also the theoretical and simulated result of BER (Bit error rate) is analyzed for different antenna configuration and finally it is investigated that the simulation result for MIMO-OFDM configuration with Alamouti STBC gives better performance where the SNR gain is 10dB at the BER value 10
⁻⁴
and 7dB at the BER value of 10
⁻³
. The effective SNR gain increases with increasing number of receiving antenna.