Spiral antenna with reconfigurable HIS using liquid crystals for monopulse radar application

• المؤلفون الرئيسيون: Mohamad, Sarah Yasmin, Cahill, Robert
• التنسيق: Conference or Workshop Item
• اللغة: English; English
• منشور في: Institute of Electrical and Electronics Engineers Inc. 2017
• الموضوعات: TK5101 Telecommunication. Including telegraphy, radio, radar, television
• الوصول للمادة أونلاين: http://irep.iium.edu.my/61407/1/merged%20-%20CAMA%202017.pdf; http://irep.iium.edu.my/61407/7/61407_Spiral%20antenna%20with%20reconfigurable%20HIS%20using%20liquid%20crystals_SCOPUS.pdf; http://irep.iium.edu.my/61407/; http://www.2017ieeecama.org/final-program/
• المؤسسة: Universiti Islam Antarabangsa Malaysia

In this paper, the design of an electronically reconfigurable ground plane composed of a high impedance surface (HIS) based on liquid crystals is presented and used as a backing structure for a two-arm Archimedean spiral antenna. The structure is used to provide electronic switching of two different shaped radiation patterns for monopulse radar application; 1) sum-pattern (Σ-pattern), and 2) difference pattern (Δ-pattern). The antenna arrangement is shown to exhibit either the Σ- or the Δ-beam by changing the permittivity (and hence reflection phase) of the HIS reflector when a bias voltage is applied between the periodic array and ground plane. The HIS is demonstrated to resonate at 6 GHz, and numerical results are employed to investigate the performance of the HIS-backed spiral arrangement, i.e. radiation pattern, impedance match, realized gain (Σ-pattern), and null depth (Δ-pattern).