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Earthquake source parameters estimated from high rate multi GNSS data: a case study of the 2022 M6.9 Menyuan earthquake

Li Xuechuan, Chen Changyun, Liang Hongbao, Li Yu, Zhan Wei

Acta Geophysica

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2023

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Vol. 71, no. 2

625--636

EN

The epicenter, origin time, and magnitude of the earthquake are critical earthquake source parameters, as they can provide data support for earthquake emergency rescue and earthquake risk research, among others. Here, the high-rate displacement time series of 11 Global Navigation Satellite System (GNSS) stations during the 2022 Menyuan M6.9 earthquake were acquired using GPS, GPS/GLONASS, and GPS/GLONASS/Galileo observations using the PRIDE PPP-AR software. Our analysis revealed that the root mean squares (RMS) of displacement derived from GPS/GLONASS/Galileo relative to GPS derived in the north, east, and up components were improved by 23.3, 34.4, and 24.4%, respectively. The epicenter location of the Menyuan earthquake based on GPS/GLONASS/Galileo-derived time series of each station was 101.201°E and 37.791°N, the earthquake origin time was 17:45:23.7 (UTC), and the moment magnitude was 6.62, which were more accurate than the GPS and GPS/GLONASS results. Although there was no significant advantage of calculating the coseismic displacement by multi-day static solution from GPS/GLONASS/Galileo, our results showed that the multi-GNSS combination can improve the stability of time series and reduce noise, and more realistically describe the surface displacement changes during earthquakes; accuracy of earthquake source parameters estimation, can, therefore, be improved with the use of multi-GNSS data.

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Performance of absolute real-time multi-GNSS kinematic positioning

Kazmierski Kamil

Artificial Satellites : Journal of Planetary Geodesy

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2018

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Vol. 53, No. 2

75--88

EN

Recently, we observe the rapid development of the Global Navigational Satellite Systems (GNSS), including autonomous positioning techniques, such as Precise Point Positioning (PPP). The GNSS have different conceptions, different spacecraft and use different types of orbits which is why the quality of real-time orbit and clock products is inconsistent, thus, the appropriate approach of the multi-GNSS observation processing is needed to optimize the solution quality. In this paper, the kinematic field experiment is conducted in order to examine multi-GNSS real-time Standard Point Positioning (SPP) and PPP performance. The test was performed on the 26 km-long car route through villages, forests, the city of Wrocaw, crossing under viaducts and a high tension line. For the first time, the solution is based on GPS + GLONASS + Galileo + BeiDou observations using streamed corrections for orbits and clocks with two different weighting scenarios. Thanks to the usage of the multi-GNSS constellation the number of positioning epochs possible to determine increases by 10%. The results show also that the appropriate weighting approach can improve the root mean square error in the SPP solution by about 13% and 42% for the horizontal and vertical coordinate components, respectively. In the case of PPP, the maximum quality improvement equals 70% for the horizontal component and the results for the vertical component are comparable with those obtained for the GPS-only solution.

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Lifetime performances of modernized GLONASS satellites: A review

Sarkar Shreya, Bose Anindya

Artificial Satellites : Journal of Planetary Geodesy

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2017

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Vol. 52, No. 4

87--97

EN

GLONASS, successfully operating during 1990s became unusable by early 2000s. Following a revitalization and modernization plan since 2004, GLONASS constellation has been completed again by the end of 2011 and the use of GLONASS is gaining popularity. Because of the previous experience, some scepticism exists among the stakeholders in using GLONASS for reliable solution and application development. This paper critically reviews the operational lifespan of GLONASS satellites launched between 2004 and 2016, as this is an important contributor towards reliability and sustained operation of the system. For popularization and extracting full benefits of GLONASS as stand-alone system or as an active component of multi-GNSS, major issues of assuring the minimum sufficient GLONASS constellation (of 24…23 satellites), efficient design implementation and the modernized ground control segment development and operation need to be properly taken care of by the system operators.

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An SDR-based Study of Multi-GNSS Positioning Performance During Fast-developing Space Weather Storm

Filić M., Filjar R., Ruotsalainen L.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2016

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Vol. 10, no. 3

395--400

EN

The understanding of the ionospheric effects on GNSS positioning performance forms an essential pre-requisite for resilient GNSS development. Here we present the results of a study of the effects of a fast-developing space weather disturbance on the positioning performance of a commercial-grade GPS+GLONASS receiver. Using experimentally collected pseudoranges and the RTKLIB, an open-source software-defined GNSS radio receiver operating in the simulation mode, we assessed GNSS positioning performance degradations for various modes of GNSS SDR receiver operation, and identified the benefits of utilisation of multi-GNSS and ionospheric error correction techniques.