Single-Layer Dual-Polarized Endfire Phased Array Antenna for 5G mm-Wave Mobile Terminals

Abstract

A single-layer dual-polarized end-fire phased array antenna is proposed for 5G millimeter-wave (mm-wave) mobile terminals. Unlike most current implementations based on multi-layer processes, only a single substrate layer with a profile of 0.14 <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">λ</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0</sub> is required in this work. Substrate integrated waveguides and tapered grounded coplanar waveguides are constructed to feed the vertical and horizontal polarizations, respectively. Two-stage grating strips and V-shaped dipoles loading provide wide bandwidth, high end-fire gain, and high front to back ratio for the two polarizations. The array exhibits a measured –10-dB impedance bandwidth of 24%, spanning the frequency range from 23.69 to 30.15 GHz. Within this operation band, the port isolation exceeds 19.5 dB and the gain fluctuations are below 4.8 dB and 6.3 dB for both polarizations, with a peak realized gain above 13 dBi. The steerable dual-polarized beam is capable of covering from –41° to +39° at 27 GHz.