A Study on Electromagnetic Scattering Characteristics of 4-D Antenna Arrays

A theoretical study on electromagnetic scattering mechanism of 4-D antenna arrays is performed for the first time. First, the scattering fields of one antenna element within an infinite 4-D array are derived under periodic boundary conditions. In order to estimate the scattering performances of 4-D antenna arrays, numerical models of the scattering fields are then established based on the traditional scattering pattern multiplication theory. Moreover, an effective time-domain full-wave approach is proposed for the scattering cross section (SCS) simulation of 4-D arrays. Finally, to verify the feasibility for SCS reduction through 4-D arrays, the differential evolution (DE) algorithm is adopted to synthesize a 14-element microstrip patch antenna array for the optimization of radiation and scattering performances. Numerical results show that 4-D arrays are capable of scattering the incident waves in both space domain and frequency domain simultaneously, thus accomplishing remarkable in-band SCS reduction.