Français

Geoflex

Opening of PPP services

Opening of a first level of operational services

68% of the points in a 2 Euro coin,
all over the world.

Eighteen months after signing with CNES exclusive and global agreements relative to the industrialization and commercialization of the PPP-CNES technology, GÉOFLEX will open on the 01/01/2018 a first level of operational services allowing a precise positioning all over the world with a precision (2D-95%) of up to 4 cm after 30 minutes of convergence with a single receiver in a PPP-IAR mode for “Precise Point Positioning with Integer Ambiguities Resolution”:

The accuracy thus obtained allows to users of such service to come back 68% of the time on the same point with an accuracy doesn't exceeding the dimension of a coin of 2 Euros, everywhere in the world, on land, at sea, and the air, months after months, years after years:

Orbits and clocks corrections for GPS, GLONASS satellites (and then for BEIDOU and GALILEO later in 2018) as well as the Uncalibrated Code Delays (UCD) and the Uncalibrated Phase Delays (UPD) corresponding to the satellites electronics biases, are modeled from observations made on a worldwide network of around one hundred GNSS permanent stations represented below:

The raw data measurements performed on this network of GNSS permanent stations are transmitted in real time and simultaneously to 2 redundant calculation centers, one located in Europe, the other in North America, to compute all the corrections affecting the different GNSS constellations tracked, a third calculation center being set up in Asia.

The users then connect to these data centers via a mobile internet access (GPRS/UMTS/LTE etc.) or SATCOM (IRIDIUM, INMARSAT, ORBCOM etc.) to retrieve these satellite dependent corrections:

Receiving orbits and clocks corrections and UCD/UPD for all the GNSS satellites, the user’s GNSS receiver, at least dual-frequencies, has to estimate by statistical methods during a convergence step of around 30 minutes the refraction of the GNSS signals when they pass through the atmosphere (ionospheric and tropospheric layers), as well as its own internal clocks biases for all the code and phase signals (decoupled clocks).

By feeding the GNSS receiver of the user with “good enough apriori” concerning the atmospheric refractions errors generated from one GNSS reference station in the surrounding (on a big city for example) or from a sparse network of GNSS permanent stations, the time to fix carrier phase ambiguities is reduced to less than 5 minutes in a mode named “PPP-RTK”.

The following illustration shows that with a network of 37 permanent stations for a country as France, the modelling tropospheric delay affecting the ORPHÉON network is similar to that one obtained with 160 GNSS permanent stations by applying a 10 parameters adaptive modelling surface with OFC (Optimal Fit Coefficients) technique (© DE OLIVEIRA et al, GPS Solution 2016: Modeling tropospheric wet delays with dense and sparse network configurations for PPP-RTK):

The different level of services hence opened are listed below, the first PPP-RTK services coming at a later date before the end of 2018:

Single-frequency PPP
multi-GNSS
RT-PPP-L1
Accuracy of 80 cm
Convergence of 30 minutes
Single-frequency PPP
multi-GNSS
+ iono. SBAS
RT-PPP-L1 "Fast and Precise"
Accuracy of 50 cm
Convergence of 1 minute
Dual-frequency PPP
multi-GNSS
with float ambiguities
RT-PPP-L1/L2
Accuracy of 10 cm
Convergence of 30 minutes
Dual-frequency PPP
multi-GNSS
with fix ambiguities
PPP-IAR
Accuracy of 4 cm
Convergence of 30 minutes
Tri-frequency PPP
multi-GNSS
with fix ambiguities
PPP-RTK
Accuracy of 2-4 cm
Convergence of 5 minutes

All these corrections, both for professionals and consumers markets, are provided in an interoperable format (RTCM3 SSR messages for “State Space Representation”), making GÉOFLEX the only “agnostic” GNSS augmentation services provider offering an easy-to-use leading-edge GNSS augmentation technology to the trade integrators, Hardware Development Kits (HDK) and Software Development Kits (SDK) may also being provided to accompany the maturation of the different markets.

For integrators or partners asking for it, their own macro-development, may be put on a marketplace to catalyze others developments, and so to bring added-value:

Through these kits including feedback to an advanced services center (log, configuration and firmware servers), integrators can quickly build new services taking advantage of precise positioning and precise timestamping, to connect the “office” and “field” parts of companies, for scanning process of the real world as a support for automation of activities:

Service opening in:

Contact us to be the first users or come see us at CES LAS VEGAS from January 8th to 12th

Back to the Geoflex website