LAUSR

A waveguide‐fed reflector antenna with high gain and multi‐beam capability is introduced and demonstrated at 220 GHz. Terahertz waves have a very small wavelength, which poses great challenges to the fabrication of terahertz antenna arrays and the connection with the T/R components. In this paper, a horn array with an element spacing less than one wavelength for terahertz frequency is presented and demonstrated, and its excitations are fan‐out using curved waveguides. The horn array is used as a feeding source of an offset parabolic reflector to achieve high‐gain and multi‐beam performance. The reflector antenna achieves four beam positions with θ = −0.7°, −0.2°, 0.2°, and 0.7°, and each beam obtains the gain of about 45 dBi. The experimental reflector antenna is fabricated and tested. Good experimental results further confirm the feasibility of the antenna and the potential application in Terahertz systems.