2D Double Semi Circular Goblet Shaped Angular Stable Dual Band Reflection Type Polarization Converter And Its Application in Radar Cross Section Reduction

Abstract

In this paper, the design and simulation of a new compact unit cell of reflection-type linear co to cross-polarization converter is proposed for C and X band applications. The unit cell consists of double semi-circular goblet shaped resonators printed on a perfect conductor-backed dielectric substrate. Periodicity of the unit cell is <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$0.243 \lambda_{0}$</tex> , where <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\lambda_{0}$</tex> is the free space wavelength at the lowest resonant frequency. The polarization conversion efficiency and its mechanism are studied carefully on the basis of surface current wave characteristics at all the three resonant frequencies within the operating bands. The structure exhibits dual band linear cross conversion from 4.71–5.68 GHz and 10.0–11.99 GHz with a polarization conversion ratio (PCR) > 90 %. Moreover, the PCR at the first and third resonant frequencies (5.2 and 11.75 GHz) shows the ideal 100 % polarization conversion efficiency while the PCR for second resonant frequency at 10.4 GHz is > 99%. The simulation results demonstrate that the proposed converter response is found to be stable at a high incidence angle of >30°. Furthermore, this proposed converter finds its potential application in enhancing the stealth ability of the modern electronic and information warfare technologies by radar cross-section (RCS) reduction. At frequencies 5.2, 10.4 and 11.75 GHz, the <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$4\times 4$</tex> array of the converter reduces the RCS by more than 12, 10 and 9 dB for both monostatic and bistatic conditions.