基于改进遗传算法的短波圆环阵列方向图综合

Synthesis of Short Wave Circular Array Direction Pattern based on Modified Genetic Algorithm

短波作为军民不可或缺的通信手段,存在着工作频带窄、抗干扰性能差等不足,而相控阵波束控制技术能够有效解决上述问题,为有效的设计短波相控阵方向图,降低副瓣电平以及提高增益,提出了一种改进遗传算法,将入侵野草算法的种子产生过程与遗传算法个体选择算子结合,计算群体适应值,适应值较高的20%以及适应值较低的10%的个体产生产生种子并随机散布到种群中,这样保留适应值较高的个体的同时也对遗传算法存在的早熟现象起到了抑制效果。并以短波四元相控阵列为模型进行了仿真,结果显示改进后的遗传算法较原遗传算法有更好的优化效果,副瓣相比于传统遗传算法降低0.7 dB的同时3 dB宽度也减少了3°,实现了很好的副瓣抑制效果,同时由适应度曲线看出,改进后的算法相比于传统算法较好的避免了早熟现象。

As an indispensable communication means for military and civilian, short-waves have some shortcomings, such as narrow working frequency band and poor anti-jamming performance. Phased array beam control technology can effectively solve the above problems. In order to effectively design the short-wave phased array pattern, reduce the sidelobe level and increase the gain, a modified genetic algorithm is proposed. By combining the seed production process of the invasive weed algorithm with the individual selection operator of the genetic algorithm, the population fitness value is calculated, and 20% individuals with higher fitness value and 10% individuals with lower fitness produce seeds and distribute them randomly into the population, which can inhibit the premature phenomena of genetic algorithm while retaining the individuals with higher fitness value. Simultaneously, the simulation with short-wave quaternary phased array done on the model indicates that the modified genetic algorithm has better optimization effect than the original genetic algorithm, the side lobes are reduced by 0.7 dB as compared with the traditional genetic algorithm, while the 3 dB width is also reduced by 3°, thus achieving good sidelobe suppression. Meanwhile, it can be seen from the fitness curve that the modified algorithm could avoid the premature phenomenon better than the traditional algorithm.