Figure 1 - available via license: Creative Commons Attribution 4.0 International
Content may be subject to copyright.
Source publication
Concerns regarding long-term effects of stray electromagnetic fields emitted by household appliances have been usually covered by mainstream and social media outlets, even though biomedical exposure studies have conclusions leaning towards low-risks. The quick deployment of Internet of Things (IoT) shows that the number of connected devices is like...
Context in source publication
Context 1
... herein obtained are not related to any health hazard conclusion, they rather focus on the experimental engineering aspect of it. Figure 1 shows the idea, an NF or FF probe samples the existing field and the receiving signal is read by an SDR (Software-Defined Radio), connected to a laptop running an application displaying frequency and amplitude data. It is a low-cost alternative to professional-grade instruments, and permits measuring domestic and industrial environments, using easily available materials and open-source software applications. ...
Similar publications
The electromagnetic spectrum is one of nature’s meagre resources. The requirements of wireless communication cannot be satisfied by the new spectrum allocation plan. A policy of self-driven spectrum allocation results as a result. Cognitive radio (CR) engineering is a brilliant technique to maximise spectrum utilisation in rapidly changing environm...
Citations
... This very high acquisition cost affects not only the scalability of such systems but also the flexibility in the context of mobility. Many recent studies [22][23][24] suggest a low-cost solution to replace such high-cost equipment in the form of Software Defined Radio technology. Software-Defined Radio (SDR) technology is a wireless communication system that uses software-based processing to perform tasks traditionally handled by dedicated hardware components, enabling flexibility and reconfigurability in radio communications. ...
The increase in channel bandwidth and peak-to-average power ratio (PAPR) of modern communication standards poses a serious challenge to performing channel power (CP) and complementary cumulative distribution function (CCDF) measurements in real-time using standard measurement solutions based on spectrum analyzers (SA). Recently, Software Defined Radio (SDR) technology has become a viable alternative to the conventional real-time spectrum monitoring approach based on SA due to its reduced cost. Therefore, in this paper, we propose a novel, innovative, agile and cost-effective solution to enable both CP and CCDF measurements on a state-of-the-art SDR platform. The proposed solution exploits the ability of the SDR equipment to access signal samples in the time domain and defines both CP and CCDF-type measurements. The two measurement functions are software implemented in GNU Radio by designing customized blocks and integrated into a graphical user interface. The proposed system was first tested and parameterized in a controlled environment using emitted signals specific to the IEEE 802.11ax family of wireless local area networks. After parameterization, the SDR-based system was used for over-the-air measurements of signals emitted in the 4G+, 5G and 802.11ax communication standards. By performing the measurement campaign, we have demonstrated the capabilities of the measurement system in performing real-time measurements on broadband channels (up to 160 MHz for IEEE 802.11ax). Altogether, we have proved the usability of CP and CCDF measurement functions in providing valuable insights into the power distribution characteristics of signals emitted by the latest communication standards. By exploiting the versatility of SDR technology, we have enabled a cost-effective solution for advanced real-time statistical measurements of modern broadband signals.
... However, these studies focused on a very specific use case, lacking generalized calibration and measurement methods. In [26], the authors show how to use an SDR to measure electromagnetic radiations emitted by home appliances. The authors use a Hack-RF dongle, a customdesigned monopole antenna, and GNU Radio to make a sensor for frequencies in the 2.4GHz band. ...
The effect of electromagnetic radiation on public health is a recurring topic in the societal and political discourse, peaking with the introduction of every new generation of cellular technology. With the introduction of 5G, promising high peak download speeds as well as high-power beams, there is a need to revisit traditional measurement approaches. ICNIRP, a.k.a the International Committee on Non-Ionising Radiation Protection, offers a useful guideline to evaluate the electromagnetic field exposure of living tissues and provides some limits to keep exposure well below the threshold where it is considered harmful. However, modern packet radio technologies such as 5G or Wi-Fi are different from old broadcasting technologies. They deliver high power in very short bursts, spread over a wide band, thus increasing the difficulty of measuring electric fields with traditional instruments, such as spectrum analyzers. In addition, 5G promises a high spatial focusing performance, which means that the field can vary significantly even in a small area. Hence, measurements with a higher spatial density than we can achieve with expensive and bulky spectrum analyzers are urgently needed. Software-defined radios (SDRs), as a size-and cost-efficient alternative, can be used to capture signals in the time domain and thus increase measurement accuracy. However, software-defined radios are not designed to be used as RF power meters. They require accurate calibration and data analysis to ensure the measured power is correct. The aim of this work is to provide a general framework to calibrate SDRs, enabling them to measure RF power and extract the corresponding electric field value. Subsequently, the influence of the SDR parameters on the accuracy of the electric field measurement is investigated. To assess the performance of the proposed calibration framework in a real-life scenario, we rely on our private 5G network with a calibrated SDR to measure the RF power from a 5G network. Our measurements show that the average electric field exposure of 5G networks is well below 1 V/m.
