Stable Gain With Frequency Selective Surface in Planar and Conformal Structure: For Radome Application

With the increase of complexity in the filter design for the structure related to the airborne platform it is best to opt for the simple solution. Thus, in this paper performance of the antenna with the stable gain for the airborne platform is analyzed when frequency selective surfaces (FSS) are inserted as a band-pass filter, both for planar and conformal structure. The analysis is performed keeping in mind the radome application. Unit cell analysis is performed using floquet boundary in CST software. Surface current distribution and s-parameters of the frequency selective surface (FSS) is observed. Designed unit cell FSS presents good angular stability and is polarization independent. Additionally, the frequency selective surface element is replicated on the planar and conformal structure as 3×3 FSS element array to observe the gain of the antenna with FSS as a performance parameter by simulating through a horn antenna. For observing the effectiveness of the filter throughout the frequency band of interest, the Insertion loss and gain of the antenna with FSS are analyzed. Comparative performance analysis at a normal incidence angle of an antenna with and without FSS structure in terms of a gain parameter is presented.