A Broadband Millimeter Wave Fixed-Beam Leaky-Wave Antenna with Stable Broadside Radiation

In point-to-point wireless communication, antennas need to radiate in a fixed direction with broadband property. However, the traditional leaky-wave antenna (LWA) is limited in broadband applications because of the beam squint effect. In this paper, a broadband fixed-beam LWA radiating at broadside is designed. A parallel plate filled with dielectric substrate is loaded on the leakage side of a ridge gap waveguide (RGW), by designing the shape of the loaded dielectric slab, the beam can be fixed at broadside in a wide frequency band of 58% (from 22 to 40 GHz). The radiation angle changes only 2.3°at broadside in the band, and the gain only has a slight deviation of 0.8 dB, which shows a good stability.