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The Automatic Precise Point Positioning Service of the Global Differential GPS System
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Processing Modes

  APPS offers 4 data processing modes, which are a combination of two data processing approaches: Static and Kinematic, and two latency options: Near Real Time a nd Most Accurate.
 
  Static data processing approach assumes that the GPS measurements were taken at a static si te, and will estimate a single set of coordinates for that site.
 
  Kinematic data processing approach assumes that the receiver (actually the antenna) could h ave been in motion on the ground or in the air, without any constraints about its speed or acceleration. A time series of (antenna) coordinates is estimated at a rate equal to the measurement rate (default) or at a slower rate (optional).
 
  Near Real Time processing will result in the quickest response from APPS, using the best GP S orbit and clock products available at the time of measurement upload:
  • If the measurements are less than 1 day old, they will be processed using the real-time GPS orbit a nd clock products of the GDGPS System. These products have a typical User Range Error (URE) better than 8cm RMS.
  • If the measurements are more than 1 day old, but are less than 1 week old, they will be processed w ith JPL's Rapid GPS orbit and clock products. These daily products have a typical URE of better than 5cm RMS.
  • If the measurements are more than 1 week old, they will be processed with JPL's Final GPS orbit and clock products. These weekly and most accurate products have a typical URE of better than 3cm RMS.
 
  Most Accurate processing will wait up to one week in order to ensure processing with JPL's most accurate GPS orbit and clock products, which are produced weekly.
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