Analysis and synthesis of conformal conical surface linear phased array with volume surface integral equation 1 AEP (Active Element Pattern) and INSGA-II

In this study, for the first time, volume-surface integral equation (VSIE) and improved NSGA-II (INSGA-II) algorithms analyse and synthesise a conformal conical surface linear phased array. The antenna element patterns and port characteristic with mutual coupling have been simulated with the VSIE algorithm. Then, the patterns of all the elements terminated by their characteristic impedances, which are called active element patterns, are measured in a microwave chamber for comparison. The results show a good match between the simulated and the measured results. The pattern of the conformal antenna array is a superposition of all these active patterns of the elements with various weights. However, the design objects containing the 3-dB beam width, side lobe levels, and beam direction must be taken into account simultaneously. So, the INSGA-II algorithm is used for a multi-object optimisation here. Moreover, by using this algorithm, the entire optimum solutions, that is, the optimum solutions of the main beam of the conformal-phased array directing to different angles, can be solved by one optimisation. Comparisons between the experimental and the simulated results show the effectiveness of the proposed approach for conformal-phased arrays.