【摘要】 正交频分复用(OFDM)与多天线(MIMO)技术的结合可以有效提高系统的性能。为了研究自适应比特分配对MIMO-OFDM系统性能的影响,首先介绍了MIMO-OFDM的系统结构和MIMO信道的奇异值分解(SVD)过程。将多载波系统中的Hughes-Hartogs自适应分配算法应用于天线数为2×2的MIMO-OFDM系统中。仿真结果表明,采用Hughes-Har-togs算法的MIMO-OFDM系统的数据速率达到甚至超过了单天线OFDM(SISO-OFDM)系统的2倍,但SVD分解也带来了巨大的运算量,提出了在MIMO-OFDM系统中使用自适应分配算法的策略。更多还原

【Abstract】 Orthogonal Frequency Division Multiplexing(OFDM) can be combined with multiple antennas to enhance the performance of wireless systems.In order to research the effects of the adaptive allocation on the performance of MIMO-OFDM system,the implementation of MIMO-OFDM system and the singular value decomposition(SVD) of MIMO channels are introduced.Based on SVD,the Hughes-Hartogs algorithm is applied in a 2×2 MIMO-OFDM system,which is an adaptive bit allocation algorithm of multiple carriers system.The simulation results show that the data rate of MIMO-OFDM system with Hughes-Hartogs algorithm is the twice or more as much as that of the SISO-OFDM system,but the SVD results in huge computational complexity.So the strategy of the applying the adaptive allocation algorithm in MIMO-OFDM system is provided.更多还原