一种新的水声MIMO空时频编码技术

基于贝尔实验室垂直分层空时编码（Vertical Bell Labs Layered Space-Time,VBLAST）的水声多输入多输出（Multiple-Input Multiple-Output,MIMO）通信技术,通过充分开发空间资源,可在不增加系统带宽的条件下成倍提高数据传输速率,是一种极具潜力的高速水下通信技术。但由于其接收信号中同时含有同频干扰及多径干扰,当信道多径扩展严重时,其性能下降严重。为此,提出一种新的空时频编码技术,该技术通过将各层信号调制到彼此正交的子载波上,不但可在接收端完全消除同频干扰,同时还能获得频率分集增益,从而使水声MIMO通信系统的性能获得极大改善。仿真及湖试结果证明了其有效性。

A novel space-time-frequency coding for underwater MIMO communication system

As a potential high speed underwater acoustic communication technique,the MIMO technique based on VBLAST coding can realize spatial multiplexing to greatly increase data rate without increasing the system bandwidth.But the received signal includes intersymbol interference and co-channel interference simultaneously,so the per-formance of system is descended seriously and especially by the seriously multipath spreading.A novel space-time-frequency coding technique is proposed to improve the MIMO system performance.It modulates every substream by orthogonal subcarrier to avoid co-channel interference and obtain frequency diversity gain.Thereby,the performance of underwater acoustic MIMO communication system can be greatly improved.Good performance of MIMO communication system based on the novel space-time-frequency coding technique is demonstrated by simula-tion and lake trial results.