加权STF在频率选择性信道中的性能分析

Performance Analysis of Weighted-STF in Frequency-selective Fading Channels

空时频编码是一种有效的编码方案,在频率选择性衰落信道中,空时频编码应用在多输入多输出正交频分复用系统中可以获得最大分集增益和编码增益。文中提出了一种新型加权空时频编码方案,该方案首先对符号进行酉星座旋转预编码,然后进行空时分组编码,根据从接收端获得的信道状态信息计算加权因子,对码字进行加权。并对采用不同加权方案的系统性能进行了仿真分析。

Space-time-frequency （STF） code is an efficient coding strategy for multi-input multi-output orthogonal frequency division multiplexing （MIMO-OFDM） systems, which could achieve both maximum diversity and coding gains over frequencyselective channels. In this paper, a new scheme Weighted-STF-OFDM （WSTF-OFDM） was proposed, which combined OFDM with unitary constellation-rotating pre-codlng, space-time block coding and weighting. The weight factors derive from the channel state information （CSI）, which was obtained from the receivers. The performance merits of our design was confirmed by corroborating simulations, and compared with existing alternatives.