摘要
在高速水声通信系统中,由于多径传播而引起的码间串扰ISI是传输误码率增加的主要原因。判决反馈均衡器(DFE)是对抗码间串扰ISI的有效方法。为了获得码间串扰为零的传输,固定遗忘因子的最小二乘递归算法(RLS)通常被用于更新DFE的抽头向量,但是这种算法在非稳定环境中并不能取得最佳表现。该文在获取均衡误差最小的即时过程中推导出一种应用在DFE中的自适应遗忘因子RLS算法。计算机仿真证明此方法对比以往的固定遗忘因子算法或可变遗忘因子算法获得了较好的传输表现。
In a high -rate underwater communication system, the delay spread due to muhipath propagation resuits in intersymbol interference （ISI） which may increase the transmission bit error rate. Decision feedhack equalizer （DFE） is an efficient approach for combating against the ISI. Recursive least squares （R/S） algorithm with a constant forgetting factor is often used to update the tap - coefficient vector of the DFE for ISI - free transmission. However, using a constant forgetting factor may not yield optimal performance in a nonstationary environment. In this paper, an adaptive forgetting factor algorithm is obtained based on on - line equalization error measurements. Computer simulation results demonstrate that better transmission performance will be achieved by using RLS algorithm with the adaptive forgetting factor than that with a constant forgetting factor or a variable forgetting factor previously proposed.
出处
《计算机仿真》
CSCD
2006年第11期102-104,共3页
Computer Simulation
关键词
递归最小二乘算法
自适应遗忘因子
信道均衡
水声通信
RLS algorithm
Adaptive forgetting factor
Channel equalization
Underwater communications
