Results 61 to 70 of about 52,670 (209)
Simulation studies of GPS radio occultation measurements
Radio Science, 2003 The atmospheric propagation of GPS signals under multipath conditions and their detection are simulated. Using the multiple phase screen method, C/A‐code modulated L1 signals are propagated through a spherically symmetric refractivity field derived from a high‐resolution radio sonde observation.
Beyerle, G., Gorbunov, M., Ao, C.
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Occultation of Radio Sources for the Linkage of Radio and Stellar Reference Frames [PDF]
Symposium - International Astronomical Union, 1990 The right ascension of the radio source 3C273B, which serves as a right ascension zero point in radio astrometric work, has been determined from lunar occultations and photographic observations.We re-analyze here the lunar occultations of 3C273B using the recent precise lunar ephemeris and obtain its right ascension referred to the FK5 equinox at J2000.
Mitsuru Sôma, M. Miyamoto, Shinko Aoki
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Algorithms, 2009 In this study different approaches based on multilayer perceptron neural networks are proposed and evaluated with the aim to retrieve tropospheric profiles by using GPS radio occultation data.
Stefania Bonafoni +2 more
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Preliminary validation of the refractivity from the new radio occultation sounder GNOS/FY-3C [PDF]
Atmospheric Measurement Techniques, 2016 As a new member of the space-based radio occultation sounders, the GNOS (Global Navigation Satellite System Occultation Sounder) mounted on Fengyun-3C (FY-3C) has been carrying out atmospheric sounding since 23 September 2013.
M. Liao +8 more
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, 2014 Although the extragalactic nature of 3C 48 and other quasi stellar radio sources was discussed as early as 1960 by John Bolton and others, it was rejected largely because of preconceived ideas about what appeared to be unrealistically high radio and optical luminosities. Not until the 1962 occultations of the strong radio source 3C 273 at Parkes, which
arxiv +1 more source
Forthcoming mutual events of planets and astrometric radio sources [PDF]
Transactions of the Institute of Applied Astronomy, 2012, Vol. 26,
pp. 39-43, 2013 Radio astronomy observations of close approaches of the Solar system planets to compact radio sources as well as radio source occultations by planets may be of large interest for planetary sciences, dynamical astronomy, and testing gravity theories. In this paper, we present extended lists of occultations of astrometric radio sources observed in the ...
arxiv
Observations and simulations of receiver-induced refractivity biases in GPS radio occultation [PDF]
, 2005 This paper has been withdrawn.
arxiv +1 more source
Initial performance of the radio occultation experiment in the Venus orbiter mission Akatsuki
Earth, Planets and Space, 2017 After the arrival of Akatsuki spacecraft of Japan Aerospace Exploration Agency at Venus in December 2015, the radio occultation experiment, termed RS (Radio Science), obtained 19 vertical profiles of the Venusian atmosphere by April 2017.
Takeshi Imamura +38 more
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Ooty Occultations of 76 radio sources
The Astronomical Journal, 1974 Positional and structural information derived from lunar occultations observed at 327 MHz is presented for 76 radio sources, most of them of flux density less than 2×10 -26 Wm -2 Hz -1 . Only 16 sources are optically identified. Two of the stronger sources in the list, viz. PKS 1417-19 and MSH 16-205 have a head-tail type of radio structure.
Vijay K. Kapahi +2 more
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Egyptian Journal of Remote Sensing and Space Sciences, 2022 Difference values between Global Positioning System (GPS)-Radio Occultation (RO) and radiosonde (RS) profiles are analyzed to assess the integration applicability between them in Egypt.
Ibrahim Fouad Ahmed +3 more
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