基于混沌的通信系统中的信道均衡

Channel Equalization in Chaos-based Communication Systems

1 引言由于Pecora和Carroll开拓性的研究[1](两个耦合的混沌系统可能实现同步,从而确定了基于混沌的通信中达到相干检波的可能性),基于混沌的通信的研究己取得迅速进展,业已提出了若干概念性的通信方法,诸如混沌遮掩、混沌相移键控[2]等.然而,这些通信系统,特别是使用相干检波类型的系统的性能要受到带宽限制、失真和噪声之类的信道物理特性的影响[3].为了让基于混沌的通信系统运行良好,信道的影响必须最小化,从而使接收机能够准确地恢复消息信号.本文的目的在于为实际通信环境下的基于混沌的通信系统设计信道均衡器.

The performance of chaos-based communication systems is greatly affected by non-ideal channel characteristics such as bandwidth limitation, distortion and additive noise. Systems that rely on coherent detection methods are particularly vulnerable because the process of regenerating the chaos basis signals in the detector involves a rather fragile process known as 'chaos synchronisation'. If channel effects can be minimized, the performance of chaos-based communication systems can be enhanced. In this paper, we study the equalization of the channel for chaotic communication systems. A channel equalizer is designed and realized by a modified recurrent neural network(RNN) for eliminating channel distortions. Results from computer simulations demonstrate the effectiveness of the equalizer as applied to a chaotic communication system.