Analysis of Airborne VHF/UHF Incidental Noise over Metropolitan Areas

Skomal, Edward N.

doi:10.1109/temc.1969.303015

Cited by 14 publications

(5 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The variability of voltage deviation appears to increase with urban density, and it may be that this variability is controlled by the spatial density of impulsive sources: Higher urban density implies the possibility of higher impulsive noise source densities, whereas more open areas physically cannot contain such sources. Parallels can be drawn with airborne studies of RF noise thermalization as a function of increasing altitude (distance from impulsive sources) over urban centers (Ploussios, ; Skomal, , ), though naturally, the distances involved are much smaller for ground‐based measurements in dense urban environments.…”

Section: Discussionmentioning

confidence: 99%

“…The work of Spaulding et al. (), and Spaulding and Disney (), as well as a series of airborne measurements over major urban areas (Cudak et al., ; Ploussios, ; Skomal, ; ; Roy, ) appear to be the only exceptions. The airborne measurements indicated that noise power was smooth (on the several kilometer scale, when measured at sufficient altitude) and approximately symmetrical about the centroid of the overflown urban area and that intentional emissions from urban areas were detectable at distances of a few hundred kilometers (again, dependent upon altitude) for airborne measurements.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Street‐Scale Mapping of Urban Radio Frequency Noise at Very High Frequency and Ultra High Frequency

et al. 2019

View full text Add to dashboard Cite

Modern measurement campaigns of man-made radio frequency (RF) noise have reported results from fixed locations that are assumed to be representative of the surroundings. Models derived from these measurements include parameters to express the variability in time and in space over very large distances (i.e., differences between cities). Despite the rapidly evolving mixture of noise sources, especially in modern urban environments, spatial variation of RF noise power at the scale of streets and blocks is essentially unknown in the very high frequency and ultra high frequency bands. Using a portable calibrated noise measurement system of our design, RF noise was recorded over a 1-MHz bandwidth for frequencies of 142.0, 246.5, and 972 MHz. Noise surveys were conducted during daytime working hours in two different neighborhoods within Boston, Massachusetts, USA, with each survey transiting a fixed, several kilometer long route, repeated twice to enable separation of temporal from spatial variability. Significant and spatially repeatable variations in median power, peak power, and voltage deviation were observed over distances of tens to hundreds of meters, dependent upon the measurement frequency. The observed spatial patterns of median and peak power appear to be repeatable on timescales of hours to weeks, and likely beyond, suggesting that these noise patterns are persistent features of the urban environment.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Street‐Scale Mapping of Urban Radio Frequency Noise at Very High Frequency and Ultra High Frequency

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The variability of voltage deviation appears to increase with urban density, and it may be that this variability is controlled by the spatial density of impulsive sources: Higher urban density implies the possibility of higher impulsive noise source densities, whereas more open areas physically cannot contain such sources. Parallels can be drawn with airborne studies of RF noise thermalization as a function of increasing altitude (distance from impulsive sources) over urban centers (Ploussios, 1968;Skomal, 1969Skomal, , 1978, though naturally, the distances involved are much smaller for ground-based measurements in dense urban environments.…”

Section: Urban Morphology and Impulsive Contentmentioning

confidence: 99%

“…Few exceptions in the literature to the "fixed site" measurement concept can be found. The work of Spaulding et al (1971), and Spaulding and Disney (1974), as well as a series of airborne measurements over major urban areas (Cudak et al, 1991;Ploussios, 1968;Skomal, 1969;1975;Roy, 1981) appear to be the only exceptions. The airborne measurements indicated that noise power was smooth (on the several kilometer scale, when measured at sufficient altitude) and approximately symmetrical about the centroid of the overflown urban area and that intentional emissions from urban areas were detectable at distances of a few hundred kilometers (again, dependent upon altitude) for airborne measurements.…”

Section: Introductionmentioning

confidence: 99%

Street‐scale mapping of urban radio frequency noise at very high frequency and ultra high frequency

Breton¹,

Haedrich²,

Kamrath³

et al. 2020

View full text Add to dashboard Cite

The U.S. Army Engineer Research and Development Center (ERDC) solves the nation's toughest engineering and environmental challenges. ERDC develops innovative solutions in civil and military engineering, geospatial sciences, water resources, and environmental sciences for the Army, the Department of Defense, civilian agencies, and our nation's public good. Find out more at www.erdc.usace.army.mil.To search for other technical reports published by ERDC, visit the ERDC online library at https://erdclibrary.on.worldcat.org/discovery.

show abstract

“…The large majority of these studies have focused on stationary, fixed location measurements taken over the course of hours and days at locations deemed representative of an area use class (Esposito & Buck, 1973;Achatz & Dalke, 2001;Wagstaff & Merricks, 2005;Wepman & Sanders, 2011;Achatz, Lo, Papazian, Dalke, & Hufford, 1998;Dalke, Achatz, Lo, Papazian, & Hufford, 1997). Several studies have conducted airborne measurements to capture variability over a city (Skomal, 1969;Skomal, 1970;Roy, 1981;Cudak, Swenson, & Cochran, 1991). The scale of these observations is on the scale of kilometers, showing the largest noise powers in the downtown and decreasing as one moves away from the city center.…”

Section: Introductionmentioning

confidence: 99%

Isarithmic mapping of radio-frequency noise in the urban environment

Haedrich¹,

Breton²,

Wilson³

2020

View full text Add to dashboard Cite

Radio-frequency (RF) background noise is a spatially-varying and critical parameter for predicting radio communication system and electromagnetic sensor performance in urban environments. Previous studies have measured urban RF noise at fixed, representative locations. The Cold Regions Research and Engineering Laboratory (CRREL) has developed a tunable system for conducting mobile RF noise measurements in the VHF and UHF and shown that urban RF noise characteristics vary significantly and repeatably at a scale of tens of meters (Haedrich & Breton, 2019). CRREL also found high-powered regions in Boston, MA that are persistent over time. However, since previous studies conducted stationary measurements or measurements along linear transects, little is known about the 2-dimensional topography of urban noise and the spatial distribution and characteristics of these high-powered regions. In this paper, we present the results of a dense, block-grid survey of downtown Boston, MA at 142 and 246.5 MHz with measurements taken every meter along each street. We present isarithmic maps of median noise power and describe the spatial distribution, shape and other characteristics of the high-powered regions. We compare the rate of noise power decay around high-powered regions to losses predicted by a power law model of path loss. 15. SUBJECT TERMS Cities and towns, Radio frequency, Radio measurements, Noise 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON a. REPORT

show abstract

Analysis of Airborne VHF/UHF Incidental Noise over Metropolitan Areas

Cited by 14 publications

References 5 publications

Street‐Scale Mapping of Urban Radio Frequency Noise at Very High Frequency and Ultra High Frequency

Street‐Scale Mapping of Urban Radio Frequency Noise at Very High Frequency and Ultra High Frequency

Street‐scale mapping of urban radio frequency noise at very high frequency and ultra high frequency

Isarithmic mapping of radio-frequency noise in the urban environment

Contact Info

Product

Resources

About