An Ultrathin Transmitarray Antenna With High Frequency Selectivity Using Antenna–Filter–Antenna Structure
Tian Hu, Tao Su, Yutong Zhao, Jianzhong Chen, Bian Wu
Abstract
In this letter, an ultrathin transmitarray antenna (TA) using an antenna–filter–antenna structure with high frequency selectivity is proposed. The high frequency selective TA element consists of a receiving (Rx) patch, a transmitting (Tx) patch, and three half-wavelength stripline resonators, which together form a fifth-order filtering response. By overturning the stub connected to the Tx patch, the 1-bit phase shift is achieved to form a desired beam. For demonstration, the equivalent circuit of the TA element is illustrated in detail. A 15 × 15-element TA prototype based on the high frequency selectivity element is designed, fabricated, and measured. The measured gain is 19.8 dBi at 5.8 GHz with 22.4% aperture efficiency. The ratio of 10 and 3 dB gain bandwidth is 1.08, corresponding to high frequency selectivity. The proposed TA is useful for improving the electromagnetic compatibility of the communication system.