Design and Fabrication of A Sub-THz Co-Reflectively Curved Patch-Reflector Antenna Array for Gain Enhancement and Near Field Focusing

This paper presents a sub-THz co-reflectively curved patch-reflector antenna array, which is a co-reflecting surface stage made by 3D stereolithography-SLA printing technology to integrate a 160 GHz, 1x4 curved patch antenna array. The co-reflecting surface stage is applied for supporting the patch antenna array made of a micromachined flexible Kapton substrate to achieve gain enhancement and near-field focusing functions. In the near-field measurement of the antenna array, - 9.34 dBm@ 160 GHz signal power is measured at a 3 mm distance to the patch array, which is consistent with the simulation results. According to the simulation results, the co-reflecting antenna array can accomplish an antenna gain of 13.3 dB, an increase of 2.4dB as compared to that without co-reflection surface design for far-field radiation. In addition, for a -19dBm power input into the antenna array, a maximum radiated energy of -11.95 dBm with 82% half-radiated energy area reduction at a distance of 4 mm to the patch array and depth of focus (DOF) of 3.05 mm can be obtained indicating the proposed antenna scheme can exhibit near-field focusing ability.