Design of a High-Gain E-band Cavity Array Antenna

A high gain cavity array antenna at E-band is presented for millimeter-wave (MMW) application. The proposed antenna array consists of four subarrays and hollow waveguide feeding network. Subsequently, each subarray is composed of a cavity, four radiating apertures, a coupling slot, and four metal blocks. Four metal blocks in the cavity are adapted to achieve high gain and low cross polarization. The simulated result shows an impedance bandwidth (|S11| <; - 10 dB) of 15% between 75 and 87 GHz. Meanwhile, the gain is achieved up to 21.6 dBi with the aperture efficiency of 90% at 81 GHz. In addition, cross polarization lower than -55 dB is obtained over the bandwidth.