Shared Aperture 4G LTE and 5G mm-Wave Antenna in Mobile Phones With Enhanced mm-Wave Radiation in the Display Direction

Radiation in the display direction of the 5G millimeter-wave (mm-wave) antenna in mobile phones is challenging due to the obstruction from the display. In this article, a shared aperture 4G LTE and 5G mm-wave antenna in mobile phones with enhanced mm-wave radiation in the display direction is studied. The 5G mm-wave array, consisting of four slot elements, is constructed in the clearance of a 4G LTE antenna. For the shared aperture design, the interdigital coupling (IDC) structure, which has a slight effect on the 4G LTE antenna, is used as the ground of the slot element. To enhance the mmwave radiation in the display direction, two groups of floating patches are applied. For the 4G LTE antenna, the measured -6 dB impedance bandwidths are 280 MHz (700-980 MHz) and 1220 MHz (1700-2920 MHz). The measured efficiency is higher than 40%. For the 5G mm-wave array, the measured overlapped -10 dB impedance bandwidth is 2.7 GHz (25.1-27.8 GHz). The measured mutual coupling among each element is lower than -16 dB. Within the 25.5-27.5 GHz, in the display direction, the measured peak gain is 10.4 dBi, and the 3 dB beam steering range reaches 90. (45.-135.) with a gain higher than 7.5 dBi.

Automated summary

This article studies a shared aperture 4G LTE and 5G mm-wave antenna in mobile phones with enhanced mm-wave radiation in the display direction. A 5G mm-wave array, consisting of four slot elements, is constructed in the clearance of a 4G LTE antenna. To enhance the mm-wave radiation in the display direction, two groups of floating patches are applied. For the 4G LTE antenna, the measured -6 dB impedance bandwidths are 280 MHz (700-980 MHz) and 1220 MHz (1700-2920 MHz). For the 5G mm-wave array, the measured overlapped -10 dB impedance bandwidth is 2.7 GHz (25.1-27.8 GHz), and the measured mutual coupling among each element is lower than -16 dB. The measured peak gain in the display direction is 10.4 dBi within the 25.5-27.5 GHz range, and the 3 dB beam steering range reaches 90 degrees (45.-135.) with a gain higher than 7.5 dBi.