Broadband Fixed-Beam Leaky-Wave Antennas Based on Tilted Radiation Apertures

In some broadband wireless communication systems, antennas need to radiate in a fixed direction with broadband property. In this paper, a broadband fixed-beam leaky-wave antenna (LWA) is proposed. When operating, the input power of the antenna is transmitted along a ridge gap waveguide (RGW), and coupled up to a series of microstrip phase delay lines through the slots, and then radiated by the printed dipoles as the radiators. Using the free bending characteristic of microstrip phase delay line, the radiation aperture direction of the antenna is changed. By designing the appropriate microstrip branch and radiation aperture direction, the antennas achieve fixed beams at ±30° in a wide frequency range from 24 to 39 GHz (a bandwidth of 47.6%).