基于 Matlab／Simulink 的天线系统自适应滤波器的仿真实现

基于 Matlab／Simulink 的天线系统自适应滤波器的仿真实现

内容简介：为了使天线系统接收和显示的信号更清晰，达到消除系统噪声和电磁干扰的目的，针对中国科学院新疆天文台南山观测基地对射电天文观测和深空探测（探月工程和火星探测）的特殊要求，利用Matlab/Simulink强大的数值计算与仿真功能实现了一种依据自适应方法滤除噪声的滤波器。首先选择脉冲星1910＋0728和1913-0440的观测信号为滤波参考信号。在Matlab上通过编写M文件设计了滤波算法并有效滤除了噪声。然后运用Simulink进行建模仿真，通过不断改变系统阶数与步长找到了滤波效果最好的自适应滤波器，确定了其最优参数为8阶，迭代步长为0.005。实验表明在这种阶数和步长下，滤波器能在保证快速滤波的前提下有效地还原接收信号的轮廓，将偏差降到最小。仿真最终结果表明自适应滤波器滤波效果良好，实用性强，满足了射电天文观测和探月的需求。

Abstract：In order to make signals received by radio-telescope antenna systems more clearly recognizable , i.e.with system noise and electromagnetic interferences reduced to desired levels , we design a type of adaptive filters and numerically simulate their performances using the powerful Matlab /Simulink tools .Ouradaptive filters are to meet the special requirements on radio-astronomy observations and deep-space explorations ( of the Moon and Mars ) at the Nanshan Station of the Xinjiang Astronomical Observatory , Chinese Academy of Sciences .In an earlier section of this paper we present signals from the pulsars 1910+0728 and 1913-0440 ( Liu Qi, private communication ) , which serve as reference signals for testing the filters.We write an algorithm in a Matlab M-file realizing the adaptive filtering .The file is easily understandable and allows other people to study .Our simulation tests with the pulsar signals show that the filters can effectively reduce the noise .In addition , we use the Simulink in the Matlab for modeling and simulating antenna systems ( including the filtering ) .By extensively changing the order and the iteration step size of a modeled filter , we find the optimal parameters for our adaptive filter:an order of eight and a step size of 0.005 .In the process , we have also verified that filters of this type can effectively restore profiles of received signals and minimize errors while fast processing signals .The simulation results and subsequent analyses of these ( particularly the results with the Simulink ) show that our adaptive filters can practically result in fine outputs and meet the needs of radio astronomy .With the rapid development of radio astronomy in China and the progress of building the 110m radio telescope in Xinjiang , filters as ours will be widely used for deep-space explorations and astronomical observations .

作者：胡开宇, 艾力·玉苏甫, 刘奇,

关键词：天线, 自适应滤波器, 脉冲星, 仿真,