Millimeter-Wave Beam-Tilted Phased Array Antenna for 5G-Enabled IoT Devices

In the realm of fifth-generation (5G)-enabled Internet of Things (IoT), the smartphone plays a pivotal role in providing users access to various IoT scenarios. With the emergence of millimeter-wave (mmWave) technology in 5G mobile terminals, it is feasible to realize an ultrabroadband, ultrahigh speed, and ultralow latency communication for advanced IoT applications. However, in a smartphone, the end-fire mmWave radiation is blocked by the metal frame. To solve this problem without altering the industrial design (ID) of the smartphone, we present a new mmWave beam-tilted phased array antenna with multiple hybrid modes operation. Our approach employs a physically oblique radiating aperture to achieve a tilted and frequency-insensitive radiation pattern, effectively addressing the interference from the smartphone platform while preserving the integrity of the ID. To expand the impedance bandwidth, monopole mode, magnetic dipole mode, and stepped patch mode are generated with an effective space utilization. For experimental validation, the proposed prototype is measured in a simplified mobile terminal. The
$1\times 4$
phased array achieves a −10 dB impedance bandwidth of 23.5–30.5 GHz, which covers the 5G n257 and n258 bands, with an in-band realized gain higher than 9.4 dBi. Furthermore, at 27.0 GHz, a wide 3-dB scanning range of 102.5°/72.0° is obtained for vertical/horizontal polarization, along with a peak gain of 9.4/11.0 dBi. The experimental results validate the proposed beam-tilted antenna solution, indicating that it can effectively address impedance mismatching, radiation distortion, low robustness, and other practical issues in 5G smartphones.