Wideband Reduction of the Metal-Frame Blockage to mm-Wave Antennas

In this paper, a method to reduce the metal-frame obstruction to the radiation of endfire mm-wave arrays with wideband operation is presented. A 7 mm-wide frame is chosen to emulate the current commercial bezel thickness. Slots of three different sizes are etched on the frame to ensure the wideband endfire behavior. The proposed solution allows the mm-wave array to radiate through the metal frame from 27.27 GHz to 37.43 GHz, which corresponds to a fractional bandwidth of 31.4 %. The presented design is compared with the free space mm-array and with the array with a normal unmodified frame. The results show that the proposed solution provides similar performance to the free space counterpart, while a 15 dBi gain improvement of the antenna array comparing to a normal frame is obtained. A good beam-steering performance can also be supported with the proposed slotted-frame structure of the mm-wave array.