Array Synthesis Using Spherical Wave Elements for EMF Compliance

Due to the advanced roll-out of 5G networks around the world, there has been an increase in public concern regarding radio frequency (RF) safety [1]. Accurate simulations are required to ensure that all mobile base stations are compliant in terms of reference limits, e.g. those published by ICNIRP [2]. These numerical simulations typically require knowledge of the antenna properties such as spherical (3D) gain, the applied power, electrical down tilt, as well as placement information. Simulation methods such as ray tracing, as described in the IEC 62232 standard [3], can be used to calculate compliance boundaries around these antennas. One of the challenges of applying this method is the formulation of the antenna array element patterns used in the exposure ratio calculation from which compliance zones are derived.