摘要：全球卫星导航系统（GPS）卫星距离地面非常远，导航信号微弱，比噪声功率还小，当接收机天线受到干扰时，导航精度变差甚至无法正常工作。压制式干扰是其中一种较为常见的干扰类型，空时联合自适应抗干扰是卫星对抗压制式干扰的有效途径，本文以此为背景开展空时联合抗干扰算法的设计。
论文根据C/A码产生原理完成了GPS卫星信号的建模；在掌握常规压制式干扰的产生方法的基础上，使用Matlab软件建立了多种压制式干扰信号模型；建立方阵阵列天线接收信号的模型；针对GPS卫星信号空间信息未知的场景，选择基于线性约束最小方差（LCMV）准则的空时联合抗干扰算法，分析LCMV准则权重系数计算方法，并使用Matlab软件设计了基于LCMV准则的空时联合抗干扰算法对GPS系统的抗干扰性能仿真软件，包括正交数字下变频、FIR滤波器、协方差计算和权重系数计算等模块，最后完成空时抗干扰算法设计，仿真分析天线阵元数、时延抽头数、采样快拍数和干扰方向对算法抗干扰性能的影响。
关键词：GPS信号，压制式干扰，LCMV，空时联合自适应抗干扰
毕业设计说明书外文摘要
Title：Analysis of the Effect of Space-time Adaptive Anti-jamming Algorithm for GPS Satellite Signal
Abstract：Global satellite navigation system (GPS) satellite is very far from the ground, the navigation signal received is weak and less than the power of noise. When the GPS receiver is jammed, the navigation accuracy becomes worse and even can not work properly. Jamming is one of the most common types of interference. Space-time joint adaptive anti-jamming method is an effective way to surpress the jamming of satellites.
In this thesis, for the array antenna, based on the C/A code generation principle, the received GPS satellite signal is modeled. Variety of suppression jamming signal, such as LFM jaming, BPSK jamming are also modeled and analyzed by using Matlab. A space-time joint anti-jamming algorithm based on linear constrained minimum variance (LCMV) criterion is applied for GPS satellite system. The weight coefficient calculation method is detailed based on the LCMV criterion. The LCMV space-time joint anti-jamming algorithm is implemented by using Matlab software, includeing orthogonal digital down-conversion, FIR filter, covariance matrix calculation and weight coefficient calculation. At last, the influence of the number of delay taps, the number of sampling shots and the direction of interference on the anti-jamming efficienty of the LCMV algorithm is simulated and summaried.
Keywords: GPS signal, Suppressive jamming, Space-time joint adaptive anti- jamming
目 次
1 绪论 2
1.1 研究背景及意义 2
1.3 本文主要内容 3
2 阵列天线GPS卫星信号与干扰建模 4
2.1 GPS卫星信号建模 4
2.1.1 GPS信号结构 4
2.1.2 C/A 伪随机扩频码 4
2.1.3 GPS信号仿真 5
2.2 压制式干扰信号建模 6
2.2.1概述 6
2.2.2点频干扰 6
2.2.3 线性调频干扰 7
2.2.4带限高斯白噪声干扰 7
2.2.5 二进制伪随机码相位调制干扰 空时联合自适应抗干扰算法对GPS卫星信号影响分析:http://www.chuibin.com/tongxin/lunwen_205967.html