Continuous Beam-Scanning Leaky-Wave Antenna With Circular Polarization Based on Modified Half-Mode SIW

A compact half-mode substrate integrated waveguide (HMSIW) leaky-wave antenna (LWA) with circular polarization (CP) is proposed in this paper. The LWA is periodically loaded with series interdigital capacitors and additional shunt branch lines as grounded stubs. This novel design is able to provide continuous beam scanning with CP by sweeping the frequency. Within the operating frequency region from 4.08 GHz to 5.16 GHz, the LWA steers CP beam ranging from -22 deg to 36 deg in the measurement.