Slot Matching for Substrate Integrated Waveguide Circularly Polarized Slot Array Antenna

Abstract

In this paper, based on the research of substrate integrated waveguide slot antenna, a new method of terminal matching by short-circuit pin and matching slot is proposed, which changes the original traveling wave array into standing wave array, and realizes a new substrate integrated waveguide (SIW) circularly polarized slot array antenna. The radiation unit of the antenna is composed of two, including an inclined angle of 45, an "octagonal" slot pair structure. The coplanar waveguide is used to feed the antenna, and the dielectric substrate with a dielectric constant of 2.2 is selected. The structure of SIW is changed from traveling wave excitation to standing wave excitation. The simulated results of 8-element line array show that VSWR≤2 and axial ratio 3dB are achieved in the frequency band of 12.32GHz~12.84GHz, and the gain is 14.8dBi at 12.55GHz near the center frequency point.