کنفرانس مهندسی برق ایران

صفحه اصلی / سی و چهارمین کنفرانس بین المللی مهندسی برق

A Satellite Tracking Monopulse Antenna Based on ‎Modulated Impedance Surfaces

نویسندگان :

Amin Azimi¹ Mohammad Amin Chaychi Zadeh² Efat Nematpour³ Amrollah Amini⁴ Vahid Nayyeri⁵

1- دانشگاه علم و صنعت ایران 2- دانشگاه علم و صنعت ایران 3- دانشگاه علم و صنعت ایران 4- دانشگاه علم و صنعت ایران 5- دانشگاه علم و صنعت ایران

کلمات کلیدی :

modulated impedance surface،monopulse antenna،leaky-wave antenna

چکیده :

This paper presents a compact monopulse leaky-wave antenna ‎based on a modulated metasurface for high-precision angle ‎tracking in spaceborne radar and communication systems. The ‎proposed antenna exploits engineered surface-impedance ‎modulation to simultaneously generate sum (Σ) and difference ‎‎(Δ) radiation patterns using two simple monopole excitations in ‎combination with a pair of parabolic reflectors. The required ‎surface-impedance distribution is realized through an isotropic ‎square patch unit-cell implemented on a grounded RO4003C ‎substrate with 1.5 mm thickness. The surface impedance ‎characteristics of the unit-cell are extracted via eigenmode ‎analysis and incorporated into a holographic synthesis ‎framework, wherein the interference between a guided surface-‎wave reference and the desired object radiation is mapped onto ‎the metasurface aperture. A leaky-wave antenna prototype ‎operating at 18 GHz is designed and numerically evaluated ‎using full-wave electromagnetic simulations. The simulated ‎results demonstrate a peak gain of 27.5 dBi for the Σ beam and ‎‎23.5 dBi for the Δ beam, with a deep null depth of −34 dBi in ‎the E-plane. The antenna achieves an aperture efficiency of ‎approximately 31%, along with excellent impedance matching ‎and high inter-port isolation exceeding 30 dB. These results ‎confirm that the proposed modulated metasurface leaky-wave ‎antenna provides a low-profile, efficient, and hardware-‎efficient solution for monopulse tracking applications.‎