Efficient Performance Modelling of a Broadband Sparse-Regular Aperture Array Antenna Element

摘要

A broadband dual-polarised antenna element is presented for a sparse-regular aperture array, for the Square Kilometre Array’s Mid-frequency Aperture Array (MFAA). The element is required to operate not only under MFAA’s specifications but also in the challenging sparse-regular array environment, where grating lobes can detrimentally affect the element’s impedance and radiation responses at numerous scan angles and frequencies. The element’s performance is modelled for a range of pertinent responses and figures-of-merit, including active reflection coefficient, intrinsic cross-polarisation ratio (IXR) and per-element receiving sensitivity. A global modelling method is also proposed to efficiently estimate the element’s sensitivity performance across the full scan and frequency range. It is shown that the proposed design has several attractive qualities for MFAA, while also possessing sufficient degrees of design freedom to improve the element’s overall performance beyond this first iteration.