A Dual-Band Leaky Wave Antenna Fed by Dual-Mode-Composite Waveguide for Microwave and Millimeter-Wave Applications

A novel dual-band leaky wave antenna with a large frequency ratio of 3.4 is presented. The antenna is fed by an air-filled dual-mode-composite waveguide with a high structure reuse ratio in the two bands where only the TE10-like mode is supported. A transverse slot array reused in the two bands with a simple geometry is elaborately designed to realize the dual-band single-harmonic radiation. A compact mode-composite waveguide to coaxial connector transition is investigated, which provides a convenient feed scheme for the dual-band antenna. The fabricated prototype verifies the implementation of forward frequency-scanning radiation in the low-frequency band of 8.7–10.5 GHz with a radiation efficiency of around 79% and in the high frequency band of 26–39.5 GHz with an efficiency of around 92%, respectively. Benefitting from the simple configurable and promising performance, the proposed antenna would be attractive for dual-band wireless applications operating at both microwave and millimeter-wave frequencies.