Designing and Performance Analysis of Low Insertion Loss with Polarization-Insensitive FSS-antenna-radome system for Airbome Applications

In this paper, an X-band frequency selective surface (FSS)-antenna-radome system has been studied for airborne applications. In order to examine the electromagnetic (EM) behavior after traversing the system, a dipole unit cell FSS and A-sandwich radome wall are developed and simulated in the first step. The -10dB relative bandwidth (BW) of the suggested single element is from 9.6 - 10.7 GHz and with a very good insertion loss (IL) of 0.1 dB. Moreover, the single element Asandwich radome wall structure has a dual band with better IL of 0.1dB and 0. 05dB from the two bands respectively. Both the suggested FSS and radome wall is analyzed for polarization-insensitivity. In the second step, we take a high directional horn antenna, which is then covered with 5 × 6 FSS array on the broadside for secure communication. Then, we design a full radome having same thickness as the unit cell radome wall. The radome is placed on the broadside covering the entire horn antenna and check the EM characteristic at X-band after passing the suggested system. We witness that $S_{11}\leq-10dB$ covering entire X-band with a high gain for the respective structures, making it applicable for airborne radome.