Results 141 to 150 of about 301 (185)

Irregularity motions in the polar ionosphere

Radio Science, 1973
The frequency spectrum of a CW HF radio signal transmitted from an aircraft and propagated over a 1‐hop path inside the polar cap was recorded for about 50 nighttime hr during August 1967. Two different general types of disturbance were observed in these records: (a) a diffuse spectral broadening which was always present to some extent, even under ...
Roy P. Basler, Thomas D. Scott, Robert L. DuPuy   +2 more
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The occurrence of large ionospheric irregularities

Journal of Atmospheric and Terrestrial Physics, 1968
Abstract Extended observations of large-scale ionospheric irregularities were made during 1963–1964 using a radio interferometer on a baseline of 10 km. The irregularities appear to be similar to those detected by the Faraday fading of satellite transmissions. A pronounced seasonal variation in the occurrence of the irregularities was observed having
S.E. Okoye, A. Hewish
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Ionospheric Irregularities and Waves

2018
Some of the fundamental scientific questions are raised, mainly focusing on the causes of mid-latitude ionospheric irregularities and waves, the upward coupling of energy in the M-I-A system, and the thermal structure. A definition is provided for irregular behaviour with appropriate examples of LSTIDs and MSTIDs in the European mid-latitude ionosphere.
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The elongation of irregularities in the equatorial ionosphere

Journal of Geophysical Research, 1963
A correlation analysis of spaced aerial fading measurements for medium-frequency radio waves scattered from the D and E regions at a location near the magnetic equator is reported. The results show that there is a slight tendency towards field-aligned elongation of the diffraction pattern on the ground for echoes from 80 and 90 km and considerable ...
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A Study of the Horizontal Irregularities of the Ionosphere

Proceedings of the Physical Society. Section B, 1950
The theory of diffraction by a random screen developed by Booker, Ratcliffe and Shinn is presented in a convenient form for practical application in ionospheric experiments. It is shown that measurements of the correlation of the fading of the reflected wave observed at spaced receiving points can be used to find the extent of the angular spreading of ...
B H Briggs, G J Phillips
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Large-scale irregularities in the ionosphere

Journal of Geophysical Research, 1963
Variations in fading period of radio signals from explorer vii satellite used to study electron density irregularities in the ...
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Ionospheric irregularities detected by GEONET

2020
<p>Ionospheric irregularities disrupt the propagation of radio waves in the frequency range below a few GHz, a band used by navigation and communication systems such as Global Navigation Satellite System (GNSS). Detailed understanding of the irregularity characteristics is helpful to estimate potential degradation of the ...
Guanyi Ma, Qi Li, Takashi Maruyama, Jinghua Li, Qingtao Wan, Jiangtao Fan, Xiaolan Wang, Jie Zhang   +7 more
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Irregular regions in the Antarctic ionosphere

Journal of Geophysical Research, 1969
Irregular regions in Antarctic ionosphere from Polar Ionosphere Beacon Satellite S-66 recordings, obtaining irregularities density from nulls ...
J. E. Titheridge, G. F. Stuart
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The characteristics of large ionospheric irregularities

Journal of Atmospheric and Terrestrial Physics, 1968
Abstract The period of the Faraday fading of 20 Mc/s satellite signals was plotted throughout 521 transits of three different satellites, at heights of 200–1600 km. From these plots the size and electron content of 2650 separate irregularities were determined. The calculated sizes were spread evenly over the observable range from 10 to 400 km.
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The Shape of Irregularities in the Upper Ionosphere

Proceedings of the Physical Society. Section B, 1955
Observations of radio stellar scintillation on a frequency of 38 Mc/s were made with three spaced receivers. Suitable records were analysed to determine the average shape of the irregularities in the amplitude pattern on the ground. It was found on all occasions that the irregularities were elongated by a factor of at least 5:1, indicating that the ...
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