针对现代战争复杂作战环境对卫星导航接收机的应用需求,研究实现GPS抗干扰接收机的关键技术。其步骤为:分析空时零陷和数字波束形成的抗干扰技术,阐述空时零陷与波束形成自适应选择的过程以及天线的布阵策略;对空时零陷和数字波束形成的抗干扰技术分别进行仿真,得出天线增益的3D立体方向图;针对接收机在冷启动时无法获得导航卫星信号的来波方向的问题,提出使用导航卫星历书和惯导模块在接收机启动时进行来波方向估计的方案,实现接收机启动时更强的抗干扰性能。研究结果表明:已知来波方向时,数字波束形成可以比空时零陷获得更强的抗干扰能力;与传统接收机相比,在冷启动时,采用空时零陷坑干扰技术的抗干扰能力至少增加8 dB。
Based on the fact that the robust of satellite navigation receiver in complex electromagnetic environment is very important in military application, the key technology of GPS anti-jamming receiver was proposed. The procedures were as follows: Space-time nulling and digital beam-forming anti-jamming methods were analyzed, then digital space-time nulling and beam-forming adaptive selection process and the antenna array were explained. Space-time nulling and digital beam-forming anti-jamming methods were simulated separately, so 3D antenna gain pattems of the two methods were obtained. Because the receiver cannot get the direction of arrival wave in cold start mode, a method used navigation satellite almanac and inertial navigation module was proposed, which estimates the direction of arrival wave that can make receiver get stronger anti-jamming ability at the initial start time. The results show that if the wave direction is known, digital beam-forming can get a stronger anti-jamming ability than space-time nulling. The method lets receiver using digital beam-forming at the start time increase more than 8 dB anti-jamming capability than the original receiver which only starts with nulling technology.