Fast Power Density Assessment of 5G Mobile Handset Using Equivalent Currents Method

Abstract

As the fifth-generation (5G) mobile communication is utilizing millimeter-wave (mmWave) frequency bands, electromagnetic field (EMF) exposure emitted from a 5G mmWave mobile handset should be evaluated and compliant with the relevant EMF exposure limits in terms of peak spatial-average incident power density. In this work, a fast power density (PD) assessment method for a 5G mmWave mobile handset using the equivalent currents (EQC) method is proposed. The EQC method utilizes the intermediate-field (IF) data collected by a spherical measurement system to reconstruct the EQCs over a reconstruction surface, and then computes the PD in close proximity of the mobile handset with acceptable accuracy. The performance of the proposed method is evaluated using a mmWave mobile handset mock-up equipped with four quasi-Yagi antennas. The assessed PD results are compared with those computed using full-wave simulations and also those measured with a planar near-field (NF) scanning system. In addition, three influencing factors related to the accuracy of the EQC method, namely, the angular resolution, the phase error, and the handset position in the IF measurements, are also analyzed. The proposed method is a good candidate for fast PD assessment of EMF exposure compliance testing in the mmWave frequency range.

Millimeter-Wave Band Electro-Optical Imaging System Using Polarization CMOS Image Sensor and Amplified Optical Local Oscillator Source

“…In this method, the simulation time depends on the simulation model resolution. Furthermore, measurement using an antenna probe requires between 40 min to 2 h of scanning per measurement, making real-time evaluation impossible [8][9][10].…”

A Study on Exposure to Electromagnetic Fields From User Equipment Antennas Above 100 GHz

“…Above 6 GHz, the reference levels are set in terms of incident power density (IPD), but it cannot be used to determine compliance in the reactive near field according to [2]. There have been a few works addressing the IPD evaluation for millimeter-wave devices e.g., [12]- [14]. Nevertheless, this paper focuses on the APD for the target frequency range.…”

A Monte Carlo Analysis of Actual Maximum Exposure From a 5G Millimeter-Wave Base Station Antenna for EMF Compliance Assessments

“…In addition, it is not clear whether the PRFs derived from the far-field radiation patterns obtained in some other studies (10)(11)(12)(13)(14) are still applicable when compliance boundaries are in the radiating near-field region. Several works, for example, Refs (18)(19)(20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30)(31), addressing the EMF compliance and assessments for lower-power mmW devices can be found in literature, but only a few (32) address the actual maximum exposure from mmW RBSs.…”