Journal ArticleDOI
Modeling attenuation and phase of radio waves in air at frequencies below 1000 GHz
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TLDR
In this article, an adequate spectroscopic data base for air consists of three terms: (1) resonance information for 29 H2O lines up to 1097 GHz and 44 O2 line up to 834 GHz in the form of intensity coefficients and center frequency for each line; (2) an empirical water vapor continuum spectrum; and (3) a liquid water attenuation term for haze and cloud conditions.Abstract:
Moist air is characterized for the frequency range 1–1000 GHz as a nonturbulent propagation medium described by meteorological parameters An adequate spectroscopic data base for air consists of three terms: (1) resonance information for 29 H2O lines up to 1097 GHz and 44 O2 lines up to 834 GHz in the form of intensity coefficients and center frequency for each line; (2) an empirical water vapor continuum spectrum; and (3) a liquid water attenuation term for haze and cloud conditions This data base is the heart of two computer programs which calculate and plot attenuation rates (in decibels per kilometer), refractivity (in parts per million), and refractive dispersion (in parts per million) The first covers the troposphere and requires pressure, temperature, and relative humidity as input data The second addresses isolated line behavior in the mesosphere wherein the geomagnetic field strength H is an additional input parameter due to the Zeeman effect of the O2 molecules Each oxygen line splits proportionally with H into numerous sublines, which are juxtaposed to form Zeeman patterns spread over a megahertz scale Patterns of three main polarization cases are considered Various typical examples for a model atmosphere demonstrate the utility of the approach, provide new information, and underline the serious role that water vapor plays above 120 GHzread more
Citations
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Journal ArticleDOI
An updated model for millimeter wave propagation in moist air
TL;DR: In this article, a practical atmospheric millimeter-wave propagation model (MPM) is proposed to predict attenuation for dry air at 2.5-430 GHz. But the model is limited to frequencies below 300 GHz and the number of spectroscopic parameters can be reduced to less than 200.
Book ChapterDOI
Attenuation by Atmospheric Gases
TL;DR: In this article, the effects of atmospheric gases, primarily oxygen and water vapor at space communications frequencies, are discussed, and methods for calculating the expected attenuation for a radiowave link are presented.
Journal ArticleDOI
ARCADE 2 MEASUREMENT OF THE ABSOLUTE SKY BRIGHTNESS AT 3-90 GHz
Dale J. Fixsen,A. Kogut,Steven Levin,Michele Limon,Philip Lubin,Paul Mirel,Michael Seiffert,Jack Singal,Edward J. Wollack,Thyrso Villela,Carlos Alexandre Wuensche +10 more
TL;DR: The ARCADE 2 data alone show an excess radio rise of 54 ± 6 mK at 3.3 GHz in addition to a CMB temperature of 2.731 ± 0.004 K.
Journal ArticleDOI
Atmospheric 60-GHz oxygen spectrum : new laboratory measurements and line parameters
TL;DR: In this paper, the absolute absorption values for pressure-broadened O2 lines in dry air were measured at frequencies from 49 to 67 GHz in 0.1-GHz increase.
Journal ArticleDOI
Arcade 2 measurement of the extra-galactic sky temperature at 3-90 ghz
D. J. Fixsen,A. Kogut,S. Levin,Michele Limon,P. Lubin,Paul Mirel,M. D. Seiffert,Jack Singal,Edward J. Wollack,T. Villela,Carlos Alexandre Wuensche +10 more
TL;DR: The ARCADE 2 data alone show an extragalactic rise of 50 ± 7 mK at 3.3 GHz in addition to a CMB temperature of 2.730 ±.004 K.
References
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Journal ArticleDOI
Shape of the 5 mm oxygen band in the atmosphere
TL;DR: In this article, the problem of absorption of microwaves by molecular oxygen in the atmosphere is treated by means of a first-order approximation to the impact theory of overlapping spectral lines.
Journal ArticleDOI
AFGL atmospheric absorption line parameters compilation: 1982 edition.
Laurence S. Rothman,Robert R. Gamache,Alain Barbe,A. Goldman,James R. Gillis,Linda R. Brown,Robert A. Toth,Jean-Marie Flaud,Claude Camy-Peyret +8 more
TL;DR: The latest edition of the AFGL atmospheric absorption line parameters compilation for the seven most active infrared terrestrial absorbers is described and the sources of the absorption parameters are summarized.
Journal ArticleDOI
The Absorption of Microwaves by Oxygen
TL;DR: In this article, the authors compared the theoretical properties of the absorption in the near-half-kilometre-wave-length regime with the theoretical dependence of absorption on pressure, and particularly interesting because of the relation to the mechanism of collision broadening and because the resonances to individual rotational lines are resolved at low pressures.
Journal ArticleDOI
Refractive-index and absorption fluctuations in the infrared caused by temperature, humidity, and pressure fluctuations
TL;DR: In this paper, the dependence of atmospheric absorption and refraction upon fluctuations in temperature, humidity, and pressure was found for infrared frequencies, including line and continuum absorption and anomalous refraction by water vapor.
Journal ArticleDOI
Absorption and dispersion in the O2 microwave spectrum at atmospheric pressures
TL;DR: In this paper, a perturbation theory proposed by Rosenkranz was tested and found to be valid for pressures up to 100 kPa (1 atm) for absorption and phase dispersion at various frequencies within the 60 GHz band of O2.