Sometimes history seems to repeat. Even in the so-called ‘mature’ technological fields. When the radio pioneers such as Heinrich Hertz, Guglielmo Marconi, and Alexander Stepanovich Popov made their first experiments of wireless transmission more than a hundred years ago using spark-gap transmitters with simple coherer-detectors they did not care which ‘frequency band’ they were using, nor did they worry about their signals being ‘spectrally efficient’ or ‘band limited’. The world of radio frequency regulation was very simple then since regulations have not yet existed. Over the years this has dramatically changed. The frequency band was subdivided into small ‘boxes’ of.
