Broadband Phased Array Spectral Domain Moment Method Analysis

With the rapid development of modern wireless electronic technology, broadband phased arrays are widely used in radar, electronic countermeasures and communication systems. The design of broadband phased arrays usually encounters the difficulties such as the large number of simulated frequency points, huge memory requirement and long CPU time. Thus, studies on the electromagnetic full wave simulation approach of broadband phased arrays have special values in terms of both the academic study and practical applications. This thesis presents some studies on a kind of broadband phased arrays based on mutual coupling, using the spectral method of moments (MoM). The thesis mainly contains the following several parts:Firstly, the thesis presents the derivation of the spectral Green's functions (GFs) for multi-layered media, based on the basic theory of spectral-domain approach. The GFs are then extended to the MOM analysis of an infinite array. Two numerical examples show the accuracy and efficiency of the method proposed in the thesis.Secondly, an optimal design of the infinite array elements for the broadband phased array with strong mutual coupling is carried out, using the combination of the spectral MoM and differential evolution algorithm. An optimized wideband phased array element with large scan angle is eventually obtained.Finally, numerical simulations on the finite broadband phased arrays are presented. By combining the Green's functions of the finite array and the spectral MoM, the computational efficiency for the analysis of relatively large arrays is improved effectively. Numerical results of the array elements in different positions are compared to those simulated by HFSS, and good agreement is obtained.