A Novel Center-Fed SIW Inclined Slot Antenna for Active Phased Array

TLDR: In this article, a center-fed substrate integrated waveguide (SIW) inclined slot array antenna is designed for a one-dimensional active phased array and a novel coaxial-to-SIW transition is employed to realize the central feed for enhancing bandwidth.

Abstract: In this paper, a center-fed substrate integrated waveguide (SIW) inclined slot array antenna is designed for a one-dimensional active phased array. A novel coaxial-to-SIW transition is employed to realize the central feed for enhancing bandwidth. The antenna prototype printed onto a single-layer Rogers 5870 is composed of 32 × 16 inclined slots working at Ku-band. As shown in measured result, the bandwidth with return loss < −10 dB is from 16.6 to 17.1 GHz, and the sidelobe levels of arrays are below −24.8 dB at 16.8 GHz in H planes. The measured gain is 31.8 dB at 16.8 GHz with the aperture efficiency of 65%. The active phased array is assembled by an antenna and 32 Tx/Rx modules, and the measured results show that the main lobe can obtain a wide-angle scanning from −45 to 45 degrees in E planes. The antenna array is suitable for low profile small active phased array radars and communication systems that require spatial wide-angle scanning.