OFDM在高速移动下的载波间干扰消除

针对正交频分复用系统的信道时变会破坏载波间的正交性而导致载波间干扰，提出了一种分段均衡有效的载波间干扰消除方法，其优点是：当采用两段和四段均衡时，在M1225信道模型下，可分别提高接收信噪比6 dB和12 dB，且与标准的均衡方法具有相同的频谱效率。性能分析与仿真验证表明，分段均衡方法能有效地消除频率偏移与信道时变而产生的载波间干扰。
关 键 词 正交频分复用; 时变信道; 载波间干扰; 分段均衡

Abstract For orthogonal frequency-division multiplexing (OFDM) communication systems, a loss of subcarrier orthogonality due to time-variant multipath channel leads to intercarrier interference (ICI).This paper studies an efficient ICI cancellation method termed segment equalization schemes.The signal-to-interference power rate can be increase 6 dB and 12 dB when the segment size is two or four, and the system has the same spectrum efficiency with standard equalization. Simulations and performance analysis show that OFDM system using the proposed segment equalization can effectively reduce the ICI cause by frequency offset and large doppler frequency shifts in mobile radio channels.
Key words orthogonal frequency-division multiplexing; time-vary channel; intercarrier interference; segment equalization