Performance of adaptive bit and power allocation MIMO-OFDM system based on greedy algorithm

In this paper, the combination of orthogonal frequency-division multiplexed (OFDM), multi-input multi-output (MIMO) and adaptive modulation can effectively eliminate or resist various fading in wireless channels, thus it can improve the capacity of system and transmission quality. Depending on the optimal bit and power allocation strategy based on greedy algorithm, in this paper, the performance of adaptive bit and power allocation MIMO-OFDM system based on greedy algorithm is completely studied. And the performance comparison among greedy algorithm, Chow algorithm and average algorithm is represented. We also compare the performance of MIMO-OFDM system under different antennas numbers. It is shown that the bit error rate (BER) of MIMO-OFDM system based on greedy algorithm is better than that based on Chow algorithm and average algorithm. And the spectral efficiency of greedy algorithm is superior to that of Chow and average algorithm. Ultimately, we show that the performance of MIMO-OFDM system is also superior to that of OFDM system with single transmit antenna and receive antenna which is under the same scheme as the former.