Man-made noise measurement programme

Currently, the levels of VHF and UHF man-made noise (MMN) in the electromagnetic environment are documented in the ITU-R recommendation (2001), based on research undertaken in the 1970s. In an effort to update this information, Mass Consultants Ltd. (MASS) conducted a measurement study on behalf of the Radiocommunications Agency (now Ofcom). The programme of work included the building of a noise measurement facility (NMF) to collect and analyse MMN data between 100 MHz and 3 GHz with bandwidths up to 10 MHz. Analysis employed the Rayleigh and Weibull distributions to model white Gaussian noise (WGN) and impulsive noise (IN) components, respectively, through the generation of the amplitude probability distribution (APD). The results of this analysis suggest that the majority of MMN is comprised of WGN and that this level is higher than previous research would suggest. The IN component has also been modeled in a form that would be suitable for inclusion in the ITU-R standard on radio noise using just the mean and standard deviation of the Weibull distribution.