Application of the hybrid butterfly mating optimization for mutual coupling suppression of tightly-coupled VLF vertical arrays

A novel method of mutual coupling suppression is proposed for mutual coupling suppression of array antennas. The proposed method is based on hybrid butterfly mating optimization(BMO). Firstly, a nonlinear optimization model is established. The optimization variables are grouped and sorted. Binary BMO (BBMO) algorithm is used to optimize the sparse of the model feeders. Then, in order to balance global search and local optimization, butterflies in standard BMO algorithm are empowered by the even chaos initialization and adaptive movement mechanism. The structure of the antenna is further optimized. The proposed method is employed to the model of the tightly two-element umbrella arrays. Results show that this method can improve the radiation resistance of phased array elements. The array gains are close to the theoretical optimum. The beam forming performance of the array antenna is improved effectively. This method provides a novel idea for mutual coupling suppression of large array antennas.