IARU voices concern over rising RF noise levels to CISPR

The IARU recently submitted a paper, written by EMC specialists Tore Worren LA9QL and Martin Sach G8KDF, to the International Special Committee on Radio Interference (CISPR) expressing concern about the problem of increasing RF noise from digital devices. The paper has been circulated to the CISPR National Committee for comment, and the IARU hopes that it will become an official CISPR Report in the future. Ultimately, the IARU hopes that CISPR will recognise the need to properly consider the cumulative impact of multiple digital devices on noise levels when developing future standards.

The paper is titled, Report on long term projects CISPR 1745L, Number of devices. It notes that sources of electromagnetic interference are more varied and prevalent than ever, and that RFI is no longer primarily from electromechanical devices but from their control systems and power supplies.

The paper also reports that the IARU has challenged CISPR on several occasions, asserting that EMI has worsened over the years, and that the increased noise levels are linked to the number of devices now potentially being sources of EMI. In this paper, the authors look at the issues and try to formulate an approach to assessment and measurement that takes into account the statistical nature of the large installed base of modern devices.

They note that for most people, the increase in the number of electrical/electronical devices over the last twenty years or so is obvious. Twenty years ago, notepads, laptops and mobile phones were in many homes but by far not in all homes, and definitely not one per person as has become the norm. LED luminaires did not exist at that time, nowadays LED based technology is the main technology for luminaires. At the same time, there has been a shift from linear power technology to noisier switching technology, found in switch mode power supplies (SMPS) and inverters which use similar techniques.

The IARU hopes that a final version of the paper will be released soon. When it is, it will be available on the IARU Region 1 website.