基于贪婪算法自适应比特功率分配的MIMO-OFDM系统性能

OFDM技术、MIMO技术和自适应调制技术的结合可以有效的抗无线信道的各种衰落,最大限度提高系统的容量和传输质量。借助于贪婪算法的最佳比特功率分配,本文深人研究了基于贪婪(greedy)算法自适应比特功率分配的MIMO- OFDM系统性能,对贪婪算法、等比特功率分配算法及CHOW算法下的系统误比特率(BER)进行比较,并对不同天线配置下的MIMO-OFDM系统的误比特率(BER)进行比较,推导及仿真结果表明：基于贪婪算法自适应比特功率分配的MIMO-OFDM系统BER要好于采用传统比特功率分配算法的系统BER,其频谱效率也要优于另外两种算法；同时,在采用相同的贪婪算法自适应动态比特分配策略下,MIMO-OFDM系统的BER要好于SISO-OFDM系统的BER。

Performance of Adaptive Bit and Power Allocation MIMO-OFDM System Based on Greedy Algorithm

The combination of OFDM,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 based on greedy algorithm,in this paper,the performance of adaptive bit and power allecation MIMO-OFDM system based on greedy algorithm is completely studied.And the bit error rate(BER)comparison among greedy algorithm,Chow algorithm and average algorithm is represented. We also compare the BER of MIMO-OFDM system under different antennas arrays.It is shown that the BER of MIMO-OFDM system based on greedy algorithm is better than that based on Chow algorithm and average algorithm.And the spectrum efficiency of greedy algorithm is superior to that of Chow and average algorithm.Ultimately,we show that BER of MIMO-OFDM system is also superior to that of SISO- OFDM system which is under the same scheme as the former.