A Microwave/Millimeter-Wave Dual-Band Shared-Aperture Antenna for S/V-Bands Applications

This paper presents a microwave/millimeter-wave dual-band shared-aperture antenna. It is designed based on a transmitarray antenna (TA) operating in the V-band, and the transmitting surface (TS) of the TA is structurally reused as a dipole antenna in the S-band. This study found that due to the large frequency ratio of the two bands, the unit cells (U Cs) of the TS are extremely small in electric size (S-band), and thus the TS can be equivalent to two metal sheets playing roles of dipole arms in the S-band. Benefiting from the spatial feeding architecture of the TA, the proposed antenna eliminates the need of complicated feeding network and features low feeding loss and high gain in the V-band. In addition, because of the efficient integration of the two kinds of antennas, the proposed antenna features a high structure reuse efficiency over the existing studies. The numerical results show that it can achieve −10 dB impedance bandwidth of 47.3% (1.84-2.98 GHz) and 3-dB gain bandwidth of 18.7% (54.8-66.1 GHz), and the peak gain in the S- and V-bands are 8.35 dBi and 28.2 dBi, respectively.