You probably know the Andersen fable of the vain emperor who was deluded enough to parade before his people dressed in new clothes that were sold to him as invisible only to those unfit for their job or hopelessly stupid. Of course, the emperor nor his court wanted to admit that they could not see the new clothes and the emperor kept “wearing” them. Eventually, the spell is broken by a young boy who does not care about status or about being stupid.
Sometimes I am reminded of that fable when seeing spectrum regulation legislation coming out of Brussels such as the Radio Equipment Directive. The RE-D, as it is called, states the essential requirements that radio equipment must meet if put on the European market. In principle, that is very sensible. Since radio spectrum is a scarce resource, responsible governments impose certain restrictions on radio equipment to limit the energy that transmitters can put into the air on their frequency of operation. This assures that other spectrum users are not burdened with excessive interference from other spectrum users.
The RE-D goes a step further: it requires not only that transmitters should be well behaved but also that receivers must withstand possibly harmful interference from other spectrum users to make effective and efficient use of the radio spectrum. European radio standards must state the technical requirements for equipment to meet to comply with this essential requirement. The feel-good factor of all this is obvious: who can argue with the need for effective and efficient use of scarce radio spectrum?
However, nobody understands how to define or measure this effective and efficient use. That should not surprise anyone familiar with radio regulations outside Europe: until very recently none of them mentions effective and efficient use of radio spectrum, never mind receiver requirements. That is because there is no common understanding of what such requirements should cover, how they are expressed and how compliance is to be measured. And what you can’t measure, you can’t apply or enforce. Such considerations were apparently of no concern to the authors of the RE-D legislation.
The Mexican government office IFT recently issued a public consultation on this very subject – see www.ift.org.mx/industria/consultas-publicas-eng/public-consultation-integration-collect-useful-information-design-spectrum-efficiency-metrics?page=1. The comment period ended on the 29th of January. The document provides an assessment of previous work by a variety of sources – including the ITU-R and the IEEE – on spectrum efficiency. It concludes there is no solid technical understanding on which to base their spectrum efficiency metrics. IFT knows it is breaking new ground and avoids putting on fancy clothes. It will be interesting to follow the results of this project.