Can a mmWave 5G Handset have Quasi-Omnidirectional Coverage?

This paper presents three handset antenna array configurations when each array is 1x4, with a capability of multiple steering angles at an operating frequency of 28GHz. The purpose is to maximize the overall achievable directivity to provide quasi-omni-directional coverage to the handset in millimeter wave (mmWave) 5G frequency bands. Generally, radiation fields from a mmWave antenna suffer high and low directivity regions that severely impact the mmWave 5G service quality. The main objective of this paper is to investigate thoroughly and provide a practical yet simple solution to this problem and ensure close to 100% coverage of a mmWave 5G handset antenna. Antenna array design and investigation around a mobile handset are studied in MATLAB, where combined (resultant) radiation patterns have been numerically calculated as a response of different antenna positions. As commonly used, a standard patch antenna is considered as the handset antenna array unit-cell while cardioid radiation pattern of the single antenna is used for analysis. An overall directivity larger than 0 dB is targeted all around the handset. The result shows that more than 95% of the spherical region can be covered with as low as 6 or 7 steering angle states when used with the proposed antenna array architecture and placement. This investigation focuses only on the handset in free space, while the same investigative approach can be extended for other scenarios like handset in the hand, or handset close of the head, etc.