Handset Frame Blockage Reduction of 5G mm-Wave Phased Arrays Using Hard Surface Inspired Structure

In this paper, the propagating characteristics of hard surfaces are employed to reduce the main beam blockage of the handset frame to horizontally polarized endfire millimeter-wave (mm-wave) arrays. To prove the concept, a quad-element vivaldi array is located at the top part of the handset and the frame with grooves is placed in front of it. The groove dimensions that form the hard surface inspired structure are studied to provide the best gain and reflection coefficient performance. The impedance bandwidth achieved is 25.3-27.5 GHz. The radiation pattern plots show that the main beam direction corresponds to endfire, the same as the original array without the frame. The mm-wave array provides beam-steering properties with a scanning angle of +-65 degrees for a realized gain higher than 7 dBi.