Ultra-Wideband Endfire Long-Slot-Excited Phased Array for Millimeter-Wave Applications

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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Original languageEnglish
Pages (from-to)3284-3293
Journal / PublicationIEEE Transactions on Antennas and Propagation
Issue number6
Online published18 Nov 2020
Publication statusPublished - Jun 2021


An ultra-wideband phased array with endfire radiation is proposed for millimeter wave (mm-wave) applications. This array consists of a linear long slot array (LSA) source and a transverse-electromagnetic (TEM) horn radiator. For each unit, a Г-shaped probe based on a substrate integrated coaxial line (SICL) is adopted to generate a primary slot source. Then, the slot flares in the E-plane with an exponential profile to form a horn unit. The antenna unit is studied with periodical boundaries (PBs) in simulation and operates from 15.4 to 46.4 GHz with active SWR < 3 for a scan angle of up to 45° in H-plane. To verify the design concept, two 1 × 16 finite arrays, Array-1 for 0° scan and Array-2 for 45° scan, are fabricated and tested. Over the operating band of 15.4–46.4 GHz, both arrays obtain good impedance matching in measurements with SWR < 2.3. The measured gain varies from 11.8 to 19.1 dBi for Array-1 and from 10 to 16.9 dBi for Array-2 within 16–40 GHz. Besides, Array-2 exhibits a scan angle of 48° and an average scan loss of 2.4 dB. Moreover, both arrays achieve a radiation efficiency exceeding 73% because of employing the low-loss SICL feed network.

Research Area(s)

  • Antennas, Broadband antennas, endfire radiation, Linear antenna arrays, long slot array (LSA), millimeter wave (mm-wave), Phased arrays, Probes, substrate integrated coaxial line (SICL), Substrates, transverse-electromagnetic (TEM) horn, Wideband, wideband phased array (WPA)