Wideband Man-Made Radio Noise Measurements in the VHF and Low UHF Bands

Abstract: Man-made radio noise measurements were conducted in a 1.16-MHz bandwidth at 112.5, 221.5, and 401 MHz at two residential and two business locations in the Boulder/Denver, Colorado, area. The measurement frequencies and bandwidth were selected using the results of a spectrum survey performed over the 104– 1060-MHz frequency range. The noise measurement data were collected as a complex baseband noise data record (consisting of six million in-phase (I) and quadrature-phase (Q) samples) every 10 minutes over a 24-hour period for each frequency and location. The data were processed to provide various statistical descriptions of the noise such as amplitude probability distributions (APDs). Median values of the antenna noise figure Fam were determined for each measurement frequency and environment type and compared to predicted values from existing man-made radio noise models. The measured values of Fam, while larger than the values predicted by the International Telecommunication Union (ITU) man-made radio noise model, were still within one standard deviation of the predicted values. Further noise measurements are recommended in a greater number of locations to provide more statistically significant results.

Keywords: man-made noise; man-made radio noise; impulsive noise; Gaussian noise; noise measurements; spectrum measurements; spectrum survey; antenna noise factor; external noise factor; amplitude probability distributions; International Telecommunications Union (ITU) radio noise model

The full report is available at http://www.its.bldrdoc.gov/publications/2553.aspx