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{{Article Infobox2
{{Article Infobox2
|Category=Fundamentals
|Category=Fundamentals
|Title={{PAGENAME}}
|Editors=GMV
|Authors=GMV
|Level=Basic
|Level=Basic
|YearOfPublication=2011
|YearOfPublication=2011
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Precise point positioning (PPP) stands out as an optimal approach for providing  centimeter-level error positioning using current and coming GNSS constellations. The Precise Point Positioning (PPP) processes measurements from a single user receiver, using detailed physical models and corrections, and precise GNSS orbit and clock products computed beforehand. PPP differs from other precise-positioning approaches like [[Real Time Kinematics|Real Time Kinematics (RTK)]] in that no reference stations are needed in the vicinity of the user. Another advantage is that since the GNSS orbit and clock products are by nature global, the PPP solutions are also global. However, it should be noted that it is possible to set up a regional PPP service using a regional network of stations.<ref name="Lainez">M.D. Laínez Samper et al, [http://mycoordinates.org/multisystem-real-time-precise-point-positioning/ Multisystem real time precise-point-positioning], Coordinates, Volume VII, Issue 2, February 2011</ref>


Precise point positioning (PPP) stands out as an optimal approach for providing  centimeter-level error positioning using current and coming GNSS constellations. The Precise Point Positioning (PPP) processes measurements from a single user receiver, using detailed physical models and corrections, and precise GNSS orbit and clock products computed beforehand. PPP differs from other precise-positioning approaches like [[Real Time Kinematic|Real Time Kinematic (RTK)]] in that no reference stations are needed in the vicinity of the user. Another advantage is that since the GNSS orbit and clock products are by nature global, the PPP solutions are also global. However, it should be noted that it is possible to set up a regional PPP service using a regional network of stations.<ref>M.D. Laínez Samper et al, [http://mycoordinates.org/multisystem-real-time-precise-point-positioning/ Multisystem real time precise-point-positioning], Coordinates, Volume VII, Issue 2, February 2011</ref>
==Galileo High Accuracy Service (HAS)==
On January 2023, the [[Galileo_High_Accuracy_Service_(HAS)|Galileo High Accuracy Service (HAS)]] was released as Initial Service. The Galileo HAS provides free of charge access, through the Galileo signal (E6-B) and by terrestrial means (Internet), to the information required to estimate an accurate positioning solution using a Precise Point Positioning algorithm in real-time.


Several software products implementing a PPP processing strategy have been developed recently by government agencies, universities, industries and individuals. There are also some online PPP services available. They are summarized in this article.
==PPP Software Online Services==


==PPP Software==
Several software products implementing a PPP processing strategy have been developed by government agencies, universities, industries and individuals, some of them are available as online services. PPP SW require the availability of precise reference satellite orbit and clock products, normally computed using a network of  GNSS reference stations distributed worldwide. The [http://www.igs.org/ International GNSS Service (IGS)] uses its [https://network.igs.org/ global network] to compute orbit and clock products used by several of the PPP providers.


Precise Point Positioning (PPP) is a global precise positioning service, since it requires the availability of precise reference satellite orbit and clock products in real-time using a network of GNSS reference stations distributed worldwide.
There are free online PPP services. When submitting RINEX observation files on each website, the data will be processed by those services and then the PPP solution is obtained and sent back.
 
*[https://gipsy-oasis.jpl.nasa.gov/ GIPSY-OASIS], or GIPSY: the GNSS-Inferred Positioning System and Orbit Analysis Simulation Software package, developed by the Jet Propulsion Laboratory (JPL), and maintained by the Orbiter and Radio Metric Systems (ORMS) group.
 
*GAPS: The University of New Brunswick (UNB) developed the GPS Analysis and Positioning Software (GAPS). According to Leandro et. al. (2007) the algorithms used in GAPS follow more or less standard PPP approaches. GAPS is available as an online processing engine via the web page http://gaps.gge.unb.ca/ppp/. Static as well as kinematic processing is possible. They accept an observation file in the RINEX 2.10 or 2.11 formats. IGS product files necessary for processing the observations are automatically retrieved from one of the IGS global data centers.
 
==PPP online Services==
   
   
*GAPS is available as an online processing engine via the web page http://gaps.gge.unb.ca/ppp/. Static as well as kinematic processing is possible. They accept an observation file in the RINEX 2.10 or 2.11 formats. IGS product files necessary for processing the observations are automatically retrieved from one of the IGS global data centers.
* gLAB Software: ESA/UPC GNSS-Lab Tool suite (gLAB) is an interactive software package for GNSS data processing and analysis, including Precise Positioning. gLAB Software is available at https://gssc.esa.int/portal/datalabs upon registration at [https://gssc.esa.int/register/ ESA GSSC Now].
 
==Regional PPP==
Blog magicGNSS:
Precise Point Positioning (PPP) is normally understood as a global positioning service, since precise satellite orbit and clock products used as input in PPP are best calculated using a network of GNSS reference stations distributed worldwide.
 
However orbit and clock corrections for PPP can also be provided over a world region in a similar way to WAAS or EGNOS corrections. It is even possible to provide a national PPP service over a single country, using national GNSS stations exclusively.
 
Satellite orbits and clocks calculated using regional stations do not have of course a high overall accuracy, but they do have a higher accuracy over the service area and, most importantly, orbit and clock errors largely cancel out over the service area. For a static or kinematic PPP user located inside the region, positioning accuracy using global or regional products is very similar.


In magicGNSS version 3.1 it is possible to evaluate the performance of regional PPP in a very simple way. Just process an ODTS scenario to calculate orbits and clocks covering the time period of your interest. On the Stations tab, select stations over your region only. Click on the station icons to select/deselect, you can use core stations and/or your own stations.
*[http://magicgnss.gmv.com/ppp/ magicPPP]: processing static and kinematic GNSS real-time data in RINEX format. Real-time orbits and clocks needed by PPP are generated internally (magicODTS). Rapid and final GPS orbits and clocks from IGS are also used, if available. MagicPPP Software is available upon [https://magicgnss.gmv.com/umf/public/registration registration]


In regional ODTS it is better to deselect “Refine Station Coordinates” in Settings. Core stations have already precise coordinates, and for your own stations you are supposed to have processed them beforehand in PPP using the “Update My Station Coordinates” option. Try also to use a longer ODTS scenario duration (3 to 4 days), in order to maximize satellite visibility. It is also important to select a good reference clock in ODTS. The reference clock time should be close enough to UTC (or GPS Time), with an offset of the order of the microsecond or less. You can see the offset of a station clock by processing it in PPP.
* [https://webapp.csrs-scrs.nrcan-rncan.gc.ca/geod/tools-outils/ppp-info.php?locale=en NRCan PPP]: provides post-processed position estimates from GPS observation files submitted by the user in RINEX format. Precise position estimates are referred to the CSRS standard North American Datum of 1983 (NAD83) as well as the International Terrestrial Reference Frame (ITRF). Single station position estimates are computed for users operating in static or kinematic modes using precise GPS orbits and clocks from IGS global data centers.


==Notes==
==Notes==
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[[Category:Fundamentals]]
[[Category:Fundamentals]]
[[Category:PPP]]

Latest revision as of 07:01, 28 August 2026


FundamentalsFundamentals
Title PPP Systems
Edited by GMV
Level Basic
Year of Publication 2011

Precise point positioning (PPP) stands out as an optimal approach for providing centimeter-level error positioning using current and coming GNSS constellations. The Precise Point Positioning (PPP) processes measurements from a single user receiver, using detailed physical models and corrections, and precise GNSS orbit and clock products computed beforehand. PPP differs from other precise-positioning approaches like Real Time Kinematics (RTK) in that no reference stations are needed in the vicinity of the user. Another advantage is that since the GNSS orbit and clock products are by nature global, the PPP solutions are also global. However, it should be noted that it is possible to set up a regional PPP service using a regional network of stations.[1]

Galileo High Accuracy Service (HAS)

On January 2023, the Galileo High Accuracy Service (HAS) was released as Initial Service. The Galileo HAS provides free of charge access, through the Galileo signal (E6-B) and by terrestrial means (Internet), to the information required to estimate an accurate positioning solution using a Precise Point Positioning algorithm in real-time.

PPP Software Online Services

Several software products implementing a PPP processing strategy have been developed by government agencies, universities, industries and individuals, some of them are available as online services. PPP SW require the availability of precise reference satellite orbit and clock products, normally computed using a network of GNSS reference stations distributed worldwide. The International GNSS Service (IGS) uses its global network to compute orbit and clock products used by several of the PPP providers.

There are free online PPP services. When submitting RINEX observation files on each website, the data will be processed by those services and then the PPP solution is obtained and sent back.

  • gLAB Software: ESA/UPC GNSS-Lab Tool suite (gLAB) is an interactive software package for GNSS data processing and analysis, including Precise Positioning. gLAB Software is available at https://gssc.esa.int/portal/datalabs upon registration at ESA GSSC Now.
  • magicPPP: processing static and kinematic GNSS real-time data in RINEX format. Real-time orbits and clocks needed by PPP are generated internally (magicODTS). Rapid and final GPS orbits and clocks from IGS are also used, if available. MagicPPP Software is available upon registration
  • NRCan PPP: provides post-processed position estimates from GPS observation files submitted by the user in RINEX format. Precise position estimates are referred to the CSRS standard North American Datum of 1983 (NAD83) as well as the International Terrestrial Reference Frame (ITRF). Single station position estimates are computed for users operating in static or kinematic modes using precise GPS orbits and clocks from IGS global data centers.

Notes


References

  1. ^ M.D. Laínez Samper et al, Multisystem real time precise-point-positioning, Coordinates, Volume VII, Issue 2, February 2011
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