Multiband antenna design with high gain and robust spherical coverage using a new 3D phased array structure for 5G mobile phone MM-wave applications

This manuscript presents a compact multi-band antenna with simple and small geometry dedicated to the millimeter-wave 5G wireless systems. The single antenna has been carefully designed on Rogers RT5880 laminate with a full dimension of 5 x 6 x 0.8 mm(3) and studied using CST microwave studio software. A fabricated prototype has been made and tested to assess the simulation results where a very good agreement has been noted. The measurement revealed that the antenna covers the frequency bands of 23.99-24.187, 25.712-26.218 and 27.761-28.361 GHz resonating at 24.1, 26 and 28 GHz, where their corresponding gain are 6.4, 6.72 and 6.65 dB respectively. In addition, the antenna is featured with a stable radiation patterns and a maximum efficiency of 93%, which express high radiation performance. The antenna equivalent circuit has been also studied where the reflection coefficient achieved is in good accord with the simulated one. Furthermore, to fight the strong path loss at the mmWave spectrum, the single antenna element has been employed to propose a new three-dimensional phased array for 5G mobile phones using four edge-mounted subarrays each is composed of 10-elements and exhibits high gain of 16.1 dB. The subarrays altogether provide a robust coverage of 180 degrees in both elevation and azimuth planes, while a full-coverage of 360 degrees has been attained in the phi-plane using beamsteering technique. Besides, an extreme isolation greater than 50 dB is attained between the subarrays. The attained results prove that the proposed antenna could highly fit the 5G mobile phone applications.