Ku-Band Radial-Line Continuous Transverse Stub Antenna With Transmit-Array Lens for High-Power Microwave Application

An antenna operating at Ku -band for high-power microwave (HPM) applications is presented in this article. The antenna can realize directional radiation of the coaxial transverse electromagnetic (TEM) mode and form a pencil beam in the desired direction. The antenna contains two parts: a radial-line continuous transverse stub antenna (RL-CTSA) as a feed antenna and two transmit-array (T-A) lenses. The RL-CTSA is designed to be a standing wave antenna, and the CTSA is step sized and arranged concentrically on the antenna aperture. The T-A lens consists of numerous elliptical-hole elements and can achieve a full transmission phase of 360° by rotating the elliptical-hole elements. An antenna prototype operating at 14.25 GHz has been designed and fabricated with an aperture radius of 300 mm. The experimental results show that the antenna has a gain of 37.9 dBi with a 21° deflection in elevation plane. The aperture efficiency reaches 75.1%, the reflectance is below −20 dB, and the radiation efficiency is more than 94.0%. Furthermore, high-power tests indicate that the power handling capacity of the antenna is higher than 250 MW.