A Low-Cost Wideband Dual Circularly Polarized Aperiodic 2-D Phased Array

Abstract

In this article, an aperiodic wideband high isolation dual circularly polarized (CP) scanning array is introduced. A novel aperiodic array optimization method based on the perturbation principle is proposed to solve the grating lobes of large spacing scanning array and thinning the number of array elements, thereby saving energy and reducing cost. The impedance bandwidth (IBW) of the proposed array element is 58%. Meanwhile, the bandwidth of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\vert S_{21}\vert &lt; -15$ </tex-math></inline-formula> dB is 42.5%, and the bandwidth of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\vert S_{21}\vert &lt; -20$ </tex-math></inline-formula> dB is 27.5%, which is better than previous reports. The 3 dB axial ratio bandwidth (ARBW) of both the left-hand circular polarization and the right-hand circular polarization is 55.4%. Furthermore, the formed 16-element aperiodic array can achieve a 2-D low side lobe level (SLL) with ±45° beam scanning across the entire operating band, improving the system’s ability to avoid interference. Compared with a 25-element compact uniform array of the same aperture, 36% transmitter and receiver components are saved. The proposed scanning array not only has high scanning performance but also has engineering versatility due to its low-cost implementation scheme.