Design of Substrate Integrated Waveguide-based Periodically-loaded Archimedean Spiral Slot Leaky Wave Antenna

Abstract

A novel structure of a periodic leaky-wave antenna with continuous beam scanning for Ku-band (12-18 GHz) applications is presented here. The design of a frequency-scanning antenna, which comprises of tapered microstrip line for feed and dual spiral slots as the radiator on the upper metallic plate of substrate integrated waveguide, is discussed. Leakage of electromagnetic energy from the leaky line (SIW) occurs through periodic loading of dual spiral slots. Antenna characteristics and performances are illustrated using full-wave simulation. The proposed LWA has features of a high gain of 13.4 dB (at broadside) with a maximum variation of 2 dB in the desired range of frequency. The designed antenna has 7 unit cells that provide directive comprehensive scanning of -60 deg. to +25 deg. over the operating frequency of 12.73-17.35 GHz with a consistent gain of 12 dB (avg.).