Preliminary report on tropospheric-scatter propagation tests using a rake receiver

Barrow, Bruce B.; Abraham, L.; Stein, Seymour; Bitzer, Donald L.

doi:10.1109/proc.1965.3966

Cited by 4 publications

(2 citation statements)

References 2 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Time periods that were windy produced broadened spectra and/or spectra with multiple maxima. Chisholm et al [ 1961 ] Results from measurements made with a Rake system [Bitzer et al, 1966] were reported by Barrow et al [1965] and Abraham et al [1966Abraham et al [ , 1967. This system makes use of cross-correlation techniques.…”

Section: Experimental Progressmentioning

confidence: 94%

Review of Techniques in Transhorizon Propagation Research and their Relationship to Parameters of the Troposphere

Cox¹

1969

Radio Science

View full text Add to dashboard Cite

Transhorizon propagation techniques and their usefulness in determining atmospheric parameters are discussed. It is concluded that the state or structure of the atmosphere cannot be inferred unambiguously from individual measurement techniques used in experiments reported to date. However, because of the sensitivity of the transhorizon radio signals to changes in the parameters of the troposphere, it is suggested that combinations of available techniques be pursued to determine the parameters uniquely.tional Academy of Sciences, Committee on Atmospheric Sciences, and was presented to the Panel in March 1968. Drift (wind) and internal motions as theyaffect the Doppler spectrum or fading of the radio signals; 2. Statistical characteristics or properties of the random fluctuations o.r variations in the atmosphere as they are related to frequency and angular dependence of the mean scattered power; 3. Nonuniformities in the statistical characteristics of the atmosphere such as inhomogeneity or anisotropy (including stratification tendencies) that exist to a scale resolvable by the measuring devices (sometimes antennas) or the technique. Much of the early work in transhorizon radio propagation was concerned with communications system applications, and the parameters measured in the experiments were usually averaged over long periods of time (many hours or even days) and over large regions of space (sometimes from just above the earth's surface to the top of the sensible atmosphere). These measurements were not very useful for determining atmospheric characteristics at any given time or location in space. For an experiment to be useful in determining atmospheric parameters, all information necessary for their determination should be contained in the radio measurements or in other measurements made simultaneously; that is, it should not be necessary to include in the interpretation any assumptions that are not supportable by the measurements themselves. Experiments that deal entirely with parameters of use only to communications system designers are not included in this review. Thus this review concerns itself with the subject of transhorizon propaga-905 906 DONALD C. COX tion only as it relates to the parameters of the atmosphere. BRIEF REVIEW OF THE THEORY Theories that attempt to describe transhorizon propagation phenomena can be classified into two groups. The models used to describe the variations or fluctuations in the refractive index of the asmosphere are the major distinguishing features of the groups. Turbulence theories. By far the greatest effort expended in describing transhorizon propagation phenomena has been based on a statistical description of turbulence in the atmosphere. A rather extensive review of this subject can be found in Staras and Wheelon, [1959]; it has been treated by many authors [e.g., ]. In this approach, the refractive index (or dielectricpermittivity) fluctuations are described as a small random change about mean level. Early work [e.g., Booker and Gordon, 1950] dealt with the time fluc...

show abstract

Section: Experimental Progressmentioning

confidence: 94%

Review of Techniques in Transhorizon Propagation Research and their Relationship to Parameters of the Troposphere

Cox¹

1969

Radio Science

View full text Add to dashboard Cite

show abstract

“…Another important development was the application to tropospheric paths of a technique involving wideband modulation and correlation detectors to resolve the multipath structure of the received signal [Barrow et al, 1965]. Arrival time spreads as large as 3 J.LS for 910 MHz over 440 km were observed.…”

Section: Transhorizon Propagationmentioning

confidence: 99%

U.S.A. National Committee Report, Fifteenth URSI General Assembly, Munich, September 1966: Commission 2, Radio Propagation in Nonionized Media; Progress in Radio Propagation in Nonionized Media

Katz¹,

Ament²,

Atlas³

et al. 1966

Radio Science

View full text Add to dashboard Cite

In 1965 there was a strong reawakening of interest in “angel” or clear‐air radar echoes. Atlas [1965] postulated that "dot" or point‐like angles were reflections from smooth, sharp boundaries at the apex of convective thermals. Focusing from the curved surface reduced the requirement on the index gradient to 1 N unit through 1 em; however, the requirement of smoothness to a fraction of a em over the first Fresnel zone is still severe and lacks experimental confirmation. Dot angel activity at night requires another explanation. Hardy, Atlas, and Glover [1966] and Deam and LaGrone [1965] conclude that dot angel characteristics are explainable only if the targets are insects. These conclusions stem from considerations of absolute cross section and wavelength dependence.

show abstract

Indirect atmospheric measurements utilizing rake tropospheric scatter techniques—Part II: radiometeorological interpretation of rake channel-sounding observations

Birkemeier

Duvoisin²,

Fontaine³

et al. 1969

Proc. IEEE

View full text Add to dashboard Cite

Preliminary report on tropospheric-scatter propagation tests using a rake receiver

Cited by 4 publications

References 2 publications

Review of Techniques in Transhorizon Propagation Research and their Relationship to Parameters of the Troposphere

Review of Techniques in Transhorizon Propagation Research and their Relationship to Parameters of the Troposphere

U.S.A. National Committee Report, Fifteenth URSI General Assembly, Munich, September 1966: Commission 2, Radio Propagation in Nonionized Media; Progress in Radio Propagation in Nonionized Media

Indirect atmospheric measurements utilizing rake tropospheric scatter techniques—Part II: radiometeorological interpretation of rake channel-sounding observations

Contact Info

Product

Resources

About