External man-made radio noise measurements

This report is the result of the work carried out at Forsvarets forskningsinstitutt (FFI) to evaluate the external man-made radio noise at different locations in Norway. To solve the task, a measurement campaign was carried out in Norway from 2013 to 2014. The measurement results from the campaign were compared to the noise levels in the categories; city, residential and rural, given in ITU Recommendation, “ITU–R P.372 Radio noise”. To our knowledge there are no data covering the external man-made noise in Norway, and the main source of the underlying data for ITU man-made noise model is from measurement campaigns in the late 1960s and early 1970s. The question is how the ITU model compares with today’s external man-made radio noise in Norway. One may expect an increase as there is more electronic equipment and devices in use today than there were 40 – 50 years ago. During the FFI measurement campaign, radio noise in the frequency range 30 – 200 MHz was measured at several locations in Norway. We used dipole antennas with an omnidirectional radiation pattern and measured the external man-made radio noise at four selected frequencies. The noise samples were post-processed to estimate the median noise power, which was converted to an external noise figure with the ITU model reference antenna. In general, the measured median external noise figure in Norway showed up to be lower than predicted by the ITU-R P.372 man-made noise model. For the city category the measured external noise figure is within the variability of the ITU data. For the residential category the measured external noise figure is lower than the ITU prediction. For the rural category the measurements indicate that the measured external noise figure is lower than the ITU prediction.