基于改进差分进化算法的机载分布式阵列栅瓣抑制方法

近年来,分布式天线阵列以其突破传统布阵环境限制的灵活性/ 高增益性成为阵列研究的热点。对于机载雷达系统,应用分布式天线阵列可以充分利用机身布阵空间资源,提高阵列的增益和空间分辨率。现有分布式优化方法多针对单元间大间距阵列与多子阵分散排布阵列,机载环境下双子阵分布式阵列优化研究极少。文章针对机载双子阵分布式阵列孔径栅瓣密集问题,提出利用差分进化算法并加以改进,实现对机载的分布式阵列栅瓣进行抑制。该方法能够在满足约束条件的同时,有效降低双子阵分布式阵列的高栅瓣问题,同时,阵列的副瓣可以被控制在较低的水平。在一定的子阵间距条件下,阵列的最大副瓣电平可以降低到-10 dB 左右。对优化算法的有效性进行蒙特卡洛实验,结果验证了该方法的可行性。

Grating Lobe Suppression of Airborne Distributed Array Based on Improved Differential Evolution Algorithm

Nowadays, distributed antenna array has been widely used due to its high gain and well flexibility of array configuration. Distributed array can be arranged flexibly on the airframe, improving the gain and space resolution of array system. The existing research on distributed array mainly aims on array with large inter-space between units or array with multi-subarray dispersed arranged, but little research focuses on two-subarray distributed array applied on aeroplane. Since the problem of dense grating lobe brought by array distributing, a optimization method based on Differential Evolution Algorithm is presented to suppress grating lobe of distributed array. The method presented can effectively lower the grating lobe level of two-subarray distributed array satisfying the constraints. Meanwhile, the sidelobe level (SLL) can be controlled at low level. In the condition of certain space between two sub-array, the maximum sidelobe level (MSLL) of array can be lowered to -10 dB. By using Monte-Carlo test, the feasibility of method is verified.