Your browser does not support JavaScript!
http://iet.metastore.ingenta.com
1887

A phase-comparison method of measuring the direction of arrival of ionospheric radio waves

A phase-comparison method of measuring the direction of arrival of ionospheric radio waves

For access to this article, please select a purchase option:

Buy article PDF
£12.50
(plus tax if applicable)
Buy Knowledge Pack
10 articles for £75.00
(plus taxes if applicable)

IET members benefit from discounts to all IET publications and free access to E&T Magazine. If you are an IET member, log in to your account and the discounts will automatically be applied.

Learn more about IET membership 

Recommend Title Publication to library

You must fill out fields marked with: *

Librarian details
Name:*
Email:*
Your details
Name:*
Email:*
Department:*
Why are you recommending this title?
Select reason:
 
 
 
 
 
Proceedings of the IEE - Part III: Radio and Communication Engineering — Recommend this title to your library

Thank you

Your recommendation has been sent to your librarian.

The most convenient research method of measuring completely the direction of arrival of waves reflected at the ionosphere appears to be that in which the phase differences of the signals received in an assembly of aerials are measured. If two pairs of similar aerials erected on lines perpendicular to each other are used, two independent phase angles may be obtained from which both angle of elevation and azimuth may be deduced.The apparatus described uses spaced coaxial loop aerials at a separation of 100 m. The signals from the aerials in a pair are amplified by means of matched receivers. The phase difference between the output signals from these receivers is displayed direct on a cathode-ray tube as the angle of inclination of the trace. With pulsed signals emitted from a suitable transmitter and with corresponding timing equipment in the receiver, the individual rays making up the total ionospheric signal may be separated from each other. The apparatus covers the frequency band 4–15 Mc/s, and the r.m.s. error of phase measurement is about 1°. Site errors, however, set a more severe limit to the accuracy of the directional measurements than do instrumental errors, and in practice it is found that, for example, over an oblique path corresponding to a range of 700 km, bearings can be measured with an accuracy of about 1° while the angle of elevation can be measured with an accuracy better than about 1½° so long as it exceeds 30°.These limitations mean that angles of elevation of E-layer reflections cannot be measured accurately at long range; it is possible, however, to obtain measurements of useful accuracy of the angle of elevation of F-layer reflections at ranges up to 1000 km or more. Bearings can be measured accurately at all ranges and for all reflections. The apparatus has so far been used principally for the study of F-layer reflections.

References

    1. 1)
      • W. Ross , E.N. Bramley . Measurements of the Direction of Arrival of Short Radio Waves Reflected at the Ionosphere. Proceedings of the Royal Society
    2. 2)
      • F.C. Williams , N.F. Moody . Ranging Circuits Linear Time-Base Generators and Associated Circuits. Journal I.E.E.
    3. 3)
      • W. Ross . Site and Path Errors in Short-Wave Direction-Finding. Journal I.E.E.
    4. 4)
      • S. De Walden , A.F.L. Rocke , J.O.G. Barrett , W.J. Pitts . The Development of a High-Frequency Cathode-Ray Direction-Finder for Naval Use. Journal I.E.E.
    5. 5)
      • J.L. Creighton . Piezo-Electric Quartz Crystals. The Post Office Electrical Engineers Journal
    6. 6)
      • R.H. Barfield , W. Ross . The Measurement of the Lateral Deviation of Radio Waves by Means of a Spaced-Loop Direction-Finder. Journal I.E.E.
    7. 7)
      • W. Ross . The Development and Study of a Practical Spaced-Loop Radio Direction-Finder for High Frequencies. Journal I.E.E.
    8. 8)
      • H.G. Hopkins , F. Horner . Direction-Finding Site Errors at Very High Frequencies. Proceedings I.E.E.
    9. 9)
      • T.L. Eckersley , F.T. Farmer . Short Period Fluctuations in the Characteristics of Wireless Echoes from the Ionosphere. Proceedings of the Royal Society
http://iet.metastore.ingenta.com/content/journals/10.1049/pi-3.1951.0061
Loading

Related content

content/journals/10.1049/pi-3.1951.0061
pub_keyword,iet_inspecKeyword,pub_concept
6
6
Loading
Correspondence
This article has following corresponding article(s):
A phase-comparison method of measuring the direction of arrival of ionospheric radio waves
This is a required field
Please enter a valid email address