An Electronically Controlled Leaky-Wave Antenna Based on Corrugated SIW Structure With Fixed-Frequency Beam Scanning

A novel electronically controlled (EC) leaky-wave antenna (LWA) based on corrugated substrate integrated waveguide (CSIW) with fixed-frequency beam-steerable capability is presented in this letter. This structure is based on a CSIW structure with rectangular ring slots and metallic vias to the ground, which realizes two isolated dc equipotential planes. Each slot of the rectangular ring is loaded with a varactor diode, and thus the series and shunt capacitance are tunable by adjusting the dc bias voltage, which eventually results in beam scanning at a fixed frequency. The proposed antenna is a single-layer structure and has a simplified dc bias network, which merely needs an inductor and a short microstrip line. An EC beam-steerable CSIW LWA is designed and experimentally validated. It is experimentally demonstrated that the radiation angle ranges from −40.66° to 31.32° as the bias voltage is tuned from 32 V to 7.5 V at 4.5 GHz.