Search Results - "Doherty, P. H."

Equatorial plasma bubbles and L-band scintillations in Africa during solar minimum by PAZNUKHOV, V. V, CARRANO, C. S, DAMTIE, B, D'UJANGA MUTONYI, F, NDEDA, J. O. H, BAKI, P, OBROU, O. K, OKERE, B, TSIDULL, G. M, DOHERTY, P. H, GROVES, K. M, CATON, R. G, VALLADARES, C. E, SEEMALA, G. K, BRIDGWOOD, C. T, ADENIYI, J, AMAESHI, L. L. N

“…We report on the longitudinal, local time and seasonal occurrence of equatorial plasma bubbles (EPBs) and L band (GPS) scintillations over equatorial Africa…”
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Impacts of ionospheric scintillations on GPS receivers intended for equatorial aviation applications by Akala, A. O., Doherty, P. H., Carrano, C. S., Valladares, C. E., Groves, K. M.

“…This study examines the impacts of ionospheric scintillations on GPS receivers that are intended for equatorial or transequatorial aviation applications. We…”
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Comparison of equatorial GPS-TEC observations over an African station and an American station during the minimum and ascending phases of solar cycle 24 by Akala, A. O., Seemala, G. K., Doherty, P. H., Valladares, C. E., Carrano, C. S., Espinoza, J., Oluyo, S.

“…GPS-TEC data were observed at the same local time at two equatorial stations on both longitudes: Lagos (6.52° N, 3.4° E, 3.04° S magnetic latitude), Nigeria;…”
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Statistics of GPS scintillations over South America at three levels of solar activity by Akala, A. O., Doherty, P. H., Valladares, C. E., Carrano, C. S., Sheehan, R.

“…This study characterizes low‐latitude scintillations at L‐band frequency in South America on daily, monthly, and seasonal time scales at three levels of solar…”
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Variability of total electron content over an equatorial West African station during low solar activity by Bolaji, O. S., Adeniyi, J. O., Radicella, S. M., Doherty, P. H.

“…Slant total electron content (STEC) data measured by the Global Positioning System receiver at Ilorin, Nigeria, with geographical coordinates 8.47°N, 4.68°E…”
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GPS observation of continent-size traveling TEC pulsations at the start of geomagnetic storms by Pradipta, R., Valladares, C. E., Doherty, P. H.

“…We report our experimental observation of continent‐size traveling plasma disturbances using GPS measurements of total electron content (TEC) over the North…”
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Simultaneous observation of traveling ionospheric disturbances in the Northern and Southern Hemispheres by VALLADARES, C. E, VILLALOBOS, J, HEI, M. A, SHEEHAN, R, BASU, Su, MACKENZIE, E, DOHERTY, P. H, RIOS, V. H

“…Measurements of total electron content (TEC) using 263 GPS receivers located in the North and South America continents are presented to demonstrate the…”
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Climatology of GPS amplitude scintillations over equatorial Africa during the minimum and ascending phases of solar cycle 24 by Akala, A. O., Amaeshi, L. L. N., Somoye, E. O., Idolor, R. O., Okoro, E., Doherty, P. H., Groves, K. M., Carrano, C. S., Bridgwood, C. T., Baki, P., D’ujanga, F. M., Seemala, G. K.

“…This study characterizes African equatorial scintillations at L-band frequency during the minimum and ascending phases of solar cycle 24. Three years’…”
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Magnetic storm effects on the variation of TEC over Ilorin an equatorial station by Adeniyi, J. O., Doherty, P. H., Oladipo, O. A., Bolaji, O.

“…We have used total electron content (TEC) derived from dual‐frequency GPS receivers to study magnetically quiet and storm time variations of the ionosphere at…”
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Statistical distribution of GPS amplitude scintillations by Akala, A.O., Doherty, P.H.

“…This study presents complementary cumulative distribution function (CCDF) as a statistical distribution apparatus for fitting GPS scintillations data. Three…”
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Ionospheric effects on GPS signals in the Arctic region using early GPS data from Thule, Greenland by El-Arini, M. B., Secan, J., Klobuchar, J. A., Doherty, P. H., Bishop, G., Groves, K.

“…Thule, Greenland, is near the magnetic North Pole, and therefore any high‐speed GPS data recorded there are of great potential import in specifying the…”
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Comparison of GPS-TEC observations over Addis Ababa with IRI-2012 model predictions during 2010–2013 by Akala, A.O., Somoye, E.O., Adewale, A.O., Ojutalayo, E.W., Karia, S.P., Idolor, R.O., Okoh, D., Doherty, P.H.

“…•We characterized GPS-TEC over Addis Ababa, Ethiopia during 2010–2013.•TEC over Addis Ababa recorded minimum values at 0400–0500 LT and maximum at 1400–1500…”
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Characterization of GNSS scintillations over Lagos, Nigeria during the minimum and ascending phases (2009–2011) of solar cycle 24 by Akala, A.O., Amaeshi, L.L.N., Doherty, P.H., Groves, K.M., Carrano, C.S., Bridgwood, C.T., Seemala, G.K., Somoye, E.O.

“…This study characterizes equatorial scintillations at L-band frequency over Lagos, Nigeria during the minimum and ascending phases of solar cycle 24. Three…”
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Comparisons of TOPEX and Global Positioning System total electron content measurements at equatorial anomaly latitudes by Vladimer, J. A., Lee, M. C., Doherty, P. H., Decker, D. T., Anderson, D. N.

“…Discrepancies exist between vertically measured ionospheric total electron content (TEC) and slant measurements of TEC that are converted to vertical with the…”
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Occurrence pattern of large-scale ionospheric irregularities over Ilorin, Nigeria - During solar cycle 24 by Oladipo, O.A., Olawepo, A.O., Adeniyi, J.O., Adimula, I.A., Willoughby, A.A., Doherty, P.H.

“…Ionospheric plasma density irregularities are regular features of the nighttime equatorial ionosphere especially around solar maximum. These irregularities…”
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Effect of geomagnetic storms on l-band scintillation over Ilorin, Nigeria by Oladipo, O.A., Olawepo, A.O., Adeniyi, J.O., Adimula, I.A., Willoughby, A.A., Doherty, P.H.

“…•Storms effects of l-band scintillation at Ilorin were investigated and reported.•Variations in Dst and Bz values were used to explain storms effect on…”
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Characterization of GPS and EGNOS amplitude scintillations over the African equatorial/low-latitude region by Akala, A.O., Oyeyemi, E.O., Arowolo, O.A., Doherty, P.H.

“…This study characterizes GPS and EGNOS amplitude scintillations over the African equatorial/low-latitude region. The data set covers January–December 2013 at…”
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Simultaneous response of NmF2 and GPS-TEC to storm events at Ilorin by Joshua, B.W., Adeniyi, J.O., Oladipo, O.A., Doherty, P.H., Adimula, I.A., Olawepo, A.O., Adebiyi, S.J.

“…•Ilorin is an African Equatorial station.•The onset time of the rise is observed to be earlier in TEC than in NmF2.•The rate of decay of TEC appears to be…”
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Assessment of IRI-2012, NeQuick-2 and IRI-Plas 2015 models with observed equatorial ionization anomaly in Africa during 2009 sudden stratospheric warming event by Bolaji, O.S., Oyeyemi, E.O., Adewale, A.O., Wu, Q., Okoh, D., Doherty, P.H., Kaka, R.O., Abbas, M., Owolabi, C., Jidele, P.A.

“…In Africa, we assessed the performance of all the three options of International Reference Ionosphere 2012, IRI-2012 (i.e. IRI-2001, IRI-2001COR and…”
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Characterization of GNSS amplitude scintillations over Addis Ababa during 2009–2013 by Akala, A.O., Ejalonibu, A.H., Doherty, P.H., Radicella, S.M., Groves, K.M., Carrano, C.S., Bridgwood, C.T., Stoneback, R.A.

“…•At Addis Ababa, highest occurrences of scintillations were recorded in April and least in June.•Scintillations over Addis Ababa were localized within the…”
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