一种基于FCGA的GPS自适应抗干扰算法

针对GPS卫星信号功率微弱易受干扰的特点,提出了一种基于浮点数编码遗传算法(Floating point number Coded Genetic Algorithm,FCGA)的GPS自适应抗干扰算法。首先分析了自适应阵的输出信号,给出了自适应阵方向图与加权矢量的关系式。然后根据线性约束最小方差准则,得到了一个有约束的多参量目标函数,并采用浮点数编码遗传算法对其进行了优化。最后为了验证该算法的有效性,以22单元改进的均匀圆形阵为研究对象,分别对自适应阵的方向图和输出信号干扰噪声比(SINR)进行了计算机仿真。结果证明,该方法能够在多个期望信号方向保持较高波束增益,同时在干扰信号方向形成很深的波束凹陷。在强干扰情况下,输出信号干扰噪声比SINR能够保持在定值附近,而不随着输入干扰功率的增加而降低,达到了抑制干扰的设计目的。

An Adaptive Algorithm Based on FCGA for GPS Interference Cancellation

Focusing on the problem that the GPS signal is susceptible to interference,an adaptive anti-jamming algorithm based on FCGA(Floating point number Coded Genetic Algorithm)is presented.First,according to the analysis of the output signal of the adaptive array,the relation formula between the radiation pattern of the adaptive array and the weighted vectors is induced.Then,the objective function with constraint conditions is obtained by LCMV criteria(Linear Constrained Minimum Variance criteria)and optimized by using the FCGA.Finally,the simulation experiment of 22-unit uniform circular array is carried out for its radiation pattern and output SINR.The results show that,by using this method,the main beam can be kept in the directions of the desired signal,and simultaneously the hollow beam is formed in the directions of the interference signal.Thus,the output SINR is not depressed,but kept constant.The goal of interference cancellation is achieved.