Phased Array Antenna Design with Improved Radiation Characteristics for Mobile Handset Applications

This paper presents a low-profile 5G phased array with improved radiation properties for smartphone applications. By modifying the structure of antenna elements from conventional slots to air-filled slot-loop resonators (with the same thickness of the substrate), the array is capable to provide high-performance radiation beams at different scanning angles, even though it is designed on an FR-4 substrate. The array contains eight slot-loop radiators. The employed elements have low profiles with discrete-feeding ports and they operate at 21-23.5 GHz. Moreover, the coupling of the radiators is less than −15 dB at the centre frequency. Well-defined and quasi end-fire radiation, good efficiency and gain levels, wide beam-steering wide operation band are the promising characteristics of the introduced array.