A Two-Dimensional Fixed-Frequency Beam-Scanning Leaky-Wave Antenna Array for Millimeter-Wave Application

A novel fixed-frequency leaky-wave antenna array (LWAA) in millimeter-wave band that achieves wide-angle scanning in both elevation and azimuth is presented in this paper. The LWAA consists of an electronically controlled holographic surface (ECHS), a gap-waveguide array (GWA), and two 16-ways power dividers. The ECHS consists of 32 rows of 1-bit amplitude modulation elements (1-bit AMEs). By loading PIN diodes, the power amplitude of each element can be independently switched between two states, hence the varying aperture field distribution can be obtained. The GWA consists of 16 parallel-arranged and separated rows of GWs, each row transmits TE ₁₀ mode waves and excites two rows of 1-bit AMEs in the form of traveling waves. A slow wave ridges are introduced in the GWs, and the appropriate phase constants are obtained by optimizing the height of the ridge. A binarized holographic method (BHM) is developed to quickly obtain antenna parameters for wide-angle scanning. An FPGA control module is designed to electrically control the antenna. Measured results verify that the proposed LWAA can achieve a scanning range of -30°~30° in elevation and -60°~60° in azimuth, and a peak gain of 25.8dBi. The developed antenna has potentials to be used in millimeter-wave communication systems.