Abstract: Adaptive OFDM(Orthogonal Frequency Division Multiplexing) system can allocate the data rates and transmit power among subcarriers adaptively, it has better BER(Bit Error Rate) performance than the traditional OFDM system in frequency selective fading channel. This article combines the adaptive OFDM system with MIMO(Multiple-input Multiple-output) technology, and utilizes the channel state information known at the transmitter, thus proposes a multi-antenna adaptive OFDM system. The simulation result shows that the system outperforms the multi-antenna OFDM system in BER performance.

Key words: adaptive OFDM, MIMO, singular value decomposition

摘要： 自适应OFDM(Orthogonal Frequency Division Multiplexing)系统根据信道情况自适应地分配各个子载波发送的比特和功率，在频率选择性衰落信道条件下，它比传统的OFDM系统有更好的误比特性能。将自适应OFDM系统与MIMO(Multiple-input Multiple-output)技术相结合，并充分利用发送端知道信道信息的条件，提出了一种多天线自适应OFDM系统，仿真结果表明，该系统与没有采用自适应算法的多天线OFDM系统相比，误比特性能有了显著提高。

关键词: 自适应OFDM, MIMO, 奇异值分解