CSRS-PPP is an on-line global Precise-Point-Positioning service for GPS data post-processing. CSRS-PPP allows GPS users to submit single or dual frequency, static or kinematic GPS raw observation data (in RINEX format) over the Internet. CSRS-PPP uses precise GPS Orbit and Clock information to determine very accurate positions in relation to the national reference frame, NAD83 or the global reference frame, ITRF.

The resultant precision can approach that of phase-differential GPS but without the need to access or process data collected simultaneously at a base station. The longer the GPS data collection period, the better the accuracy.

GPS Precise Point Positioning (POST PROCESSING)

Static mode
Static processing will produce one averaged corrected position for the entire file submitted. For any location in Canada (or the world), regardless of the proximity to an ACP, CSRS-PPP (static) is the ideal tool for easily computing, with centimetric accuracy, the integrated coordinates of a base station used in a differential or RTK survey. This in fact provides NAD83-CSRS geodetic control where none exists and permits the entire survey to be tied to the NAD83-CSRS datum.

Kinematic mode
Kinematic processing will produce a corrected position for every single "point" in the file. It can be used for applying corrections to a track of raw data collected by a moving GPS receiver. But with movement also comes the increased possibility of obstructions (trees, buildings, overpasses) interrupting the GPS satellite signals and making it very difficult for a GPS receiver to initialize (or "solve ambiguities"). Sub-meter, and better, accuracies can be attained in kinematic mode only once the GPS receiver has successfully initialized (which can take anywhere from 10 min to 2 hrs depending on receiver quality and the amount of obstructions or signal interruptions). If initialization does not occur then accuracy is limited to that of the "code solution" (30 cm to meters depending on the receiver used). This technique is recommended for wide-open locations, is ideally suited for places like the Canadian North especially above the tree line and has even been used for airborne applications.

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