Tunable slot antenna backed by substrate integrated waveguide cavity

In this article, we present a new frequency reconfigurable SIW cavity antenna feed with a GCPW transmission line. The studied design consists of a slotted cavity backed antenna tuned by the integration of three varactor diodes in the radiating slot. The antenna has a compact size with an overall dimensions of 29.6 x 34.8 x 0.508 mm(3). By changing the DC biasing voltages of the three diodes, the resonant frequency vary within a wide range of 0.9 GHz while maintaining stable radiation patterns oriented in the broadside direction. Besides, the antenna gain remains greater than 4.5 dBi in the frequency range of agility. The proposed antenna was fabricated and tested in an anechoic chamber and the measured results were well correlated with the simulation. The proposed antenna can offer a significant income for many applications such as the radars and the satellite communications.