Real-time isotropic measurement system based on Software Defined Radio

The spatial and temporal variability of signals used in modern communication standards calls for an in-situ, agile electromagnetic fields (EMF) measurement solution, capable of following extremely rapid temporal and spatial variations. In this article we propose an original approach in addressing real-time isotropic field measurements based on multichannel software defined radio (SDR). We have designed a custom application for retrieving simultaneous channel power measurements in three synchronized radiofrequency channels enabling data acquisition and processing. The proposed system was used for measuring signals emitted by a device operating in the Long-Term Evolution-Advanced (LTE-A) and IEEE 802.11ax Wi-Fi standard, in different usage scenarios. In none of the measured scenarios did the measured field values exceed the limitations imposed by the ICNIRP standard. By designing this measurement system, we have proved the capabilities of this type of SDR in performing channel power measurement on multiple radiofrequency input channels, with the capability to store and access the measured data in time. The measurement system is versatile, operates in real-time and could be used for various purposes other than exposure assessment.