A Wideband C-shaped Open Slot Array for Millimeter-wave Applications

In this paper, we propose a wideband and high-gain planar antenna array for millimeter-wave applications. In this array, the slot radiator with a C-shaped and open structure is used as the antenna element. Due to the travelling-wave radiation of the open slot, the slot radiator can produce a wideband radiation and have an impedance bandwidth of 40% with the |S11| below –10dB from 21.6 GHz to 32.6 GHz. The gain of the proposed antenna element is up to 12.5 dBi owning to its large radiation aperture formed by two C-shaped open slot. Based on this wideband and high-gain antenna element, we design an 8 × 8 antenna array with a 1-to-64 SIW full-corporate feed network. The proposed array is fabricated in a two-layer substrate using standard printed circuit board (PCB) technology. The measured results show that the proposed antenna array has an impedance bandwidth of 37% from 21.4 to 31GHz. The measured gain of the proposed array is from 26.3 to 28.4 dBi over the operating bandwidth, with an average radiation efficiency of 70%. With wide bandwidth and the high directive gain, the proposed antenna array is a good candidate for long-distance millimeter-wave communications.