Compact Dual-Polarized End-Fire Phased Array Antenna With Zero Ground Clearance for 5G mm-Wave Mobile Terminals

A compact dual-polarized end-fire phased array antenna with zero ground clearance is presented for 5G mm-wave mobile terminals. A double-layer twisted substrate integrated waveguide with a plated through hole fence is developed for vertical polarization, and the microstrip line-fed dipole is further integrated to produce horizontal polarization. Both are capable of covering the n257 and n261 bands, while no ground clearance is required. A compact 1 × 4 phased array is constructed with the antenna length and element spacing of only 2.65 mm and 5.5 mm. The realized gain reaches 9.7 dBi for both polarizations and the 3-dB beam steering range is ±45°.