Zobrazeno 1 - 10
of 136
pro vyhledávání: '"D. Venkata Ratnam"'
Autor:
R. Mukesh, Sarat C. Dass, Negash Lemma Gurmu, M. Vijay, S. Kiruthiga, S. Mythili, D. Venkata Ratnam, V. B. S. Srilatha Indira Dutt
Publikováno v:
Advances in Astronomy, Vol 2024 (2024)
This paper presents forecast and investigation of the variation in ionospheric Total Electron Content (TEC) during the solar eclipses (SEs) of December 2019 and June 2020 using three different methods: Deep Autoregressive model (DeepAR), Feed-Forward
Externí odkaz:
https://doaj.org/article/d543af5d5ce947bd8c26134612d1b99c
Publikováno v:
IEEE Access, Vol 10, Pp 22161-22168 (2022)
Scale the ionosonde ionograms to produce accurate readings is a professional manual scaling technique. However, there is a high demand for auto-scaling software that can manage a large number of ionograms in order to avoid the time and effort involve
Externí odkaz:
https://doaj.org/article/b1ce7f63fbde43deb54fe00e793b95ab
Autor:
K. Siva Krishna, D. Venkata Ratnam
Publikováno v:
AIMS Electronics and Electrical Engineering, Vol 5, Iss 3, Pp 194-205 (2021)
Multi Global Navigation Satellite System (GNSS) plays an essential role in navigation and geodesy fields for positioning, Navigation, and Timing (PNT) services. The predominant challenge of multi-GNSS is hardware bias errors such as Differential code
Externí odkaz:
https://doaj.org/article/d31d3edc27544baaa27c74881016f5c0
Autor:
K. Siva Krishna, D. Venkata Ratnam
Publikováno v:
Geodesy and Geodynamics, Vol 11, Iss 2, Pp 97-105 (2020)
Delay bias between the pseudo range code is called Differential Code Bias (DCB), this is one of the main error sources to estimate the precise Total Electron Content (TEC) in ionosphere. Differential delay biases between the dual frequency band signa
Externí odkaz:
https://doaj.org/article/52fb083dbc954b65bf36d0cc214d6b80
Publikováno v:
IEEE Access, Vol 8, Pp 54535-54553 (2020)
The single-frequency users of Global Navigation Satellite System (GNSS) require an effective mathematical model that mitigate the dominant errors due to ionospheric delays. Klobuchar model approximately reduces ionospheric effect up to 50% through it
Externí odkaz:
https://doaj.org/article/698753691d914182b769cdaef275f6e1
Autor:
P. Babu Sree Harsha, D. Venkata Ratnam
Publikováno v:
IEEE Access, Vol 8, Pp 57879-57890 (2020)
In this paper, ground based Global Positioning System (GPS) Total Electron Content (TEC) observations collected from the GPS Aided GEO Augmented Navigation (GAGAN) network over low latitude Indian subcontinent are assimilated into the Thermosphere Io
Externí odkaz:
https://doaj.org/article/8a4f92e65ce745189db92bcc35e049b1
Ionospheric time delay corrections based on the extended single layer model over low latitude region
Publikováno v:
Geodesy and Geodynamics, Vol 10, Iss 3, Pp 235-240 (2019)
Ionospheric delay error is considered to be one of the most prominent factors impacting the Global Navigation Satellite Systems (GNSS) positioning and navigation accuracies. Due to dispersive nature and anisotropic of the ionosphere above certain reg
Externí odkaz:
https://doaj.org/article/105b144099e94b28a86d218dbe13221b
Publikováno v:
IEEE Access, Vol 6, Pp 66954-66962 (2018)
Navigation with Indian constellation (NAVIC) is the operational name given to the Indian Regional Navigation Satellite System developed by the Indian Space Research Organisation, India. The most influential factor is ionospheric gradients that can de
Externí odkaz:
https://doaj.org/article/f9cd39634214456dbaa9a0b19645e713
Publikováno v:
Geodesy and Geodynamics, Vol 8, Iss 5, Pp 305-310 (2017)
Space weather phenomena cause satellite to ground or satellite to aircraft transmission outages over the VHF to L-band frequency range, particularly in the low latitude region. Global Positioning System (GPS) is primarily susceptible to this form of
Externí odkaz:
https://doaj.org/article/159e8767f7594b14af5cae95eaa9c394
Publikováno v:
Aviation, Vol 20, Iss 1 (2016)
The ionosphere is the region of the upper atmosphere and the study of the upper atmosphere has a significant role in monitoring, modeling and forecasting for satellite based navigation services. As India lies in a low latitude region, a more careful
Externí odkaz:
https://doaj.org/article/98affffc9e544979b80f8f9a1269de7e