Measuring very high frequency and ultrahigh frequency radio noise in urban environments : a mobile measurement system for radio-frequency noise
Haedrich, Caitlin E.; Breton, Daniel J.
Radio-frequency (RF) background noise is an important parameter in designing and predicting performance of RF communication and sensor systems. Modern man-made RF noise consists of unintentional emissions from sources such as electronic devices, power transmission lines, and internal combustion engine ignitions. Governments and academia have previously measured RF noise at fixed, representative locations within the urban environment. Considering the heterogeneous mix of office buildings, retail and residential buildings, transportation hubs, and parks that com-promise modern cities, we hypothesize that RF-noise power varies significantly throughout the urban environment. To characterize this variability, we present a mobile, tunable RF-noise measurement system designed to record frequencies from 63 MHz to 1 GHz in a 1 MHz to 10 MHz bandwidth. This report describes the system design, including the choice of preselection filters, preamplifiers, and RF shielding necessary to measure low RF-noise levels while avoiding inter-modulation distortion problems that arise in an environment with many strong emitters. Additionally, we describe techniques developed to reliably geolocate RF data in urban environments. GPS (global positioning system) reception is often poor in dense urban environments. We mitigate this issue by using a 1 m surveying wheel for geolocation.
Cold Regions Research and Engineering Laboratory (U.S.)Engineer Research and Development Center (U.S.)
Cities and towns; Impulsive; Mapping; Noise; Radio frequency; Radio measurements; Spatial; Thermal noise; Urban; Y-factor
Technical Report (Engineer Research and Development Center (U.S.)) ; no. ERDC/CRREL TR-19-8
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