Satellite navigation ionospheric service

Home
Stations
Deviation

Deviation

Signal deviation is a systematic error which must be controlled and compensated precisely for satellite navigation ionospheric and precise positioning applications. As one of IGS multi-mode GNSS deviation analysis centers, Chinese Academy of Sciences has provided IGS GNSS relative formal deviation DCB and absolute formal deviation OSB products since 2016, covering all open frequency points and signals of BDS2/3, GPS, GLONASS, Galileo and QZSS.

Absolute Pseudo-distance Deviation OSB

BDS GPS Galileo GLONASS QZSS

Relative Pseudo-distance Deviation DCB

BDS GPS Galileo GLONASS QZSS
Modeling

Modeling

By using Beidou /GNSS, ocean altimeter, DORIS and other high-precision data, combined with global spherical harmonic model, regional improved spherical harmonic model and local generalized trigonometric series model, a fast and accurate spatial ionospheric approach modeling method based on "pseudo-stability idea" was established. An accurate ionospheric simulation and efficient correction model of "global precision - regional refinement - local refinement" has been formed.

Prediction of the TEC

Forecast the Ion for 1 Day Forecast the Ion for 2 Day Forecast the Ion for 5 Day Fast Ionosphere

Real-time TEC

Global Real-time Global Combined China Region US Region European Region

New Content

new content
Disturbance

Disturbance

Ionospheric gradient, scintillation and other disturbance effects are one of the most difficult problems restricting the accurate and reliable service of Beidou /GNSS. A perturbation fine detection method based on ROTI, GIX, AATR, amplitude and phase scintillation index was constructed to make full use of the regional/global intensive real-time GNSS observation resources. Real-time monitoring, accurate modeling and short-term prediction of ionospheric gradient and scintillation effect were realized.

Global

ROTI Products Amplitude Scintillation Phase Scintillation

China

ROTI Products GIX Products Amplitude Scintillation Phase Scintillation
Applications

Applications

Fine monitoring and error control of space ionospheric delay, gradient and scintillation effects are very important for navigation and communication applications. Based on ground-based GNSS/DORIS, ocean altimetry and low-orbit occultation ionospheric observation data, ARTEMIS real-time ionospheric correction data service performance and its influence on precise positioning were analyzed.

Analysis of Product Accuracy

IGS-GIM GNSS-dSTEC DORIS-dSTEC Jason-TEC

Precision Analysis of SF PPP

Positioning Accuracy Gain Convergence Time Comparison
About

Latest Data

Introduction

The ionospheric gradient effect is one of the difficult problems that restrict the accurate and reliable service of Beidou /GNSS. With the ionospheric TEC change rate index ROTI as the representative, the ROTI index spatial meshization method based on IDW was established on the basis of real-time GNSS observation data and real-time ROTI calculation of line of sight direction of each reference station, and the global scale real-time fine monitoring of ionospheric gradient effect was realized.

Product Standard

Specification	Description
Provider	Chinese Academy of Sciences(CAS)
Data Input	Global/regional real-time GNSS reference station data
Number of Stations	400-500 Worldwide
System Frequency	BDS B1/B3, GPS L1/L2, GAL E1/E5
Data Sampling Rate	1HZ
Data Processing	ROTI exponential meshing method based on IDW
Coverage Area	-90°N–90°N, 180°W–180°E
Thin Layer Height	450km
Spatial Resolution	2.5° Lat × 5.0° Lon
Data Interval	5 minutes
Data Format	Custom（IONEX-like）