Irkutsk State University
Irkutsk, Russian Federation
Irkutsk, Russian Federation
Irkutsk, Russian Federation
In 2011, ISTP SB RAS began to deploy a routinely operating network of receivers of global navigation satellite system signals. To date, eight permanent and one temporal sites in the Siberian region are operating on a regular basis. These nine sites are equipped with 12 receivers. We use nine multi-frequency multi-system receivers of Javad manufacturer, and three specialized receivers NovAtel GPStation-6 designed to measure ionospheric phase and amplitude scintillations. The deployed network allows a wide range of ionospheric studies as well as studies of the navigation system positioning quality under various heliogeophysical conditions. This article presents general information about the network, its technical characteristics, and current state, as well as the main research problems that can be solved using data from the network.
ionosphere, GNSS, GPS, GLONASS, Beidou, total electron content, scintillations, Javad, NovAtel
ВВЕДЕНИЕ
В последние двадцать лет глобальные навигационные спутниковые системы (ГНСС) стали существенной частью экономической (в широком смысле) деятельности человека [Hofmann-Wellenhof et al., 2008]. На первом этапе существовало две ГНСС: американская система GPS (Global Positioning System) и российская ГЛОНАСС (Глобальная навигационная спутниковая система). В настоящее время практически завершено развертывание ГНСС Beidou/Compass в Китае, запущено более половины группировки европейской системы Galileo, развертываются спутники поддержки SBAS (Satellite Based Augmentation System).
С одной стороны, ГНСС обеспечили возможность для достаточно точной независимой навигации, что нашло широкое применение в строительстве, сельском хозяйстве, авиации, картографии и других областях. С другой стороны, ГНСС дают новый богатый экспериментальный материал по физике ионосферы, атмосферы, а также геодинамике. В области физики ионосферы появилось большое количество работ, основанных на двухчастотных фазовых измерениях, выполняемых приемниками ГНСС. Первые работы велись в основном с использованием системы GPS по причине наличия достаточного числа станций и стабильно ра
ботающей орбитальной группировки. В последние годы широко используется отечественная система ГЛОНАСС и все активнее используются альтернативные ГНСС, такие как Beidou/Compass [Kunitsyn et al., 2016] и SBAS [Kunitsyn et al., 2015]. В ионосферных исследованиях основным параметром, определяемым с помощью ГНСС-измерений, является полное электронное содержание (ПЭС, TEC — Total Electron Content). Единица измерения ПЭС — TECU (Total Electron Content Unit), 1 TECU=1016 м–2.
Значительная часть опубликованных работ, связанных с ГНСС-исследованиями ионосферы, посвящена изучению ионосферных неоднородностей различного масштаба [Афраймович, Перевалова, 2006; Jakowski et al., 2012a; Afraimovich et al., 2013; Otsuka et al., 2013; Ding et al., 2014] и ионосферных мерцаний [Aarons, 1997; Mitchell et al., 2005], картированию ионосферы [Hernández-Pajares et al., 2009] и определению абсолютных ионосферных параметров [Ясюкевич и др., 2017a; Lanyi, Roth, 1988], а также ГНСС-радиотомографии ионосферы [Ruffini et al., 1998; Mitchell, Spencer, 2003; Nesterov, Kunitsyn, 2011]. Широкое применение находит технология ассимиляции. Ассимиляционные модели, например Utah State University Global Assimilation of Ionospheric Measurements (USU-GAIM) Model [Schunk et al., 2004] или модель Центральной аэрологической обсерватории Росгидромета [Solomentsev et al., 2012], используются как для научных исследований физики процессов, так и для решения ряда других задач. В прикладном аспекте ГНСС используются для корректировки радиотехнических систем [Afraimovich, Yasukevich, 2008; Ясюкевич и др., 2017б], включая радарные системы [Ovodenko et al., 2015], для улучшения качества моделей [Arikan et al., 2016], что особенно актуально в системах реального времени [Zolesi et al., 2004].
Развивается направление построения индексов состояния ионосферы и околоземного космического пространства на основе данных ГНСС. В настоящий момент широко известен индекс ROTI — Rate-of-TEC index [Pi et al., 1997] и его улучшенные версии AATR — Along Arc TEC Rate [Juan et al., 2018] и DIX — Disturbance Ionosphere indeX [Jakowski et al., 2012b]. Существуют индексы, показывающие возмущенность ионосферы локально [Voeykov et al., 2016], регионально [Nesterov et al., 2017] и глобально [Gulyaeva, Stanislawska, 2008]. Кроме того, разработана методика оценки общего уровня ионосферной плазмы — глобального электронного содержания (ГЭС) [Afraimovich et al., 2008], основанная на технологии глобальных ионосферных карт (GIM — Global Ionosphere Maps) [Mannucci et al., 1998; Schaer et al., 1998].
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Работа выполнена в рамках базового финансирования программы ФНИ II.16 на оборудовании центра коллективного пользования «Ангара», http://ckp-rf.ru/ckp/3056. Обработка рядов вариаций ПЭС выполнена в рамках гранта Российского научного фонда проект № 17-77-20005.
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65. URL: ftp://ftp.sonel.org/gps/data (accessed October 1, 2018).
66. URL: ftp://ftp.trignet.co.za (accessed October 1, 2018).
67. URL: https://hive.geosystems.aero (accessed October 1, 2018).
68. URL: http://smartnet-ru.com (accessed October 1, 2018).
69. URL: https://eft-cors.ru (accessed October 1, 2018).
70. URL: http://rtknet.ru (accessed October 1, 2018).
71. URL: https://simurg.iszf.irk.ru (accessed October 1, 2018).
72. URL: http://ckp-rf.ru/ckp/3056 (accessed October 1, 2018).
73. URL: http://omniweb.gsfc.nasa.gov (accessed October 1, 2018).
