Terahertz Array-Feed Reflector Antenna for Wide-Angle Retrodirective and Adaptive Tracking Communication System

This letter proposes a retrodirective array-feed reflector antenna for terahertz adaptive tracking communication systems. The gain reaches 35.3 dB at 216 GHz when the antenna works in single-horn-feed mode with receiving, and the side lobe level (SLL) is lower than −25 dB. And for the retrodirective mode with transmitting, it automatically forms a reflected wave pointing to the direction of the incident wave. At vertical incidence, the retrodirective gain reaches 41.2 dB, and the scanning coverage corresponding to a 3 dB gain drop reaches ±22.5º. Measured results show that the proposed antenna is well matched, with reflections below −14.5 dB from 172 to 260 GHz. This antenna is suitable for retrodirective and adaptive tracking systems and terahertz communication systems.