<html><head></head><body><div style="font-family: Verdana;font-size: 12.0px;"><div>Hello there,</div>
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<div>as a new member of the mailing list, I first want to introduce myself: I am a university geodesy student at Technical University of Munich, Bavaria, Germany, and currently I'm writing on my master's thesis about investigation of Precise Point Positioning (PPP) for static performance.</div>
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<div>For that reason, I use the free software RTKlib version 2.4.2 p13 for postprocessing of RINEX data. The observation time for all investigated stations holds about 1.75 hrs.</div>
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<div>For that, I use IGS correction data together with RINEX observation data of GPS, GLONASS, Galileo and BeiDou. In one of my tries, I selected the mode "PPP Static" with combined Kalman filtering (forward and backward), where for each epoch (data sampling rate 1s) a solution is generated. The attached picture shows the 2D groundtrack solution for one station with these settings; the result of the first epoch is specially marked.</div>
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<div>My question now is: Can anybody answer why this groundtrack solution seems to fulfill a "loop", i. e. why the positioning solution for first and last epoch are that close to each other (I have checked: They are not identical!!). I have already tried to find out about PPP static mode in RTKlib, but without success, so far :(.</div>
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<div>If anybody can help, I would be very pleased about an answer to my e-mal thuber25@web.de. Thank you very much in advance for your help!</div>
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<div>Best regards,</div>
<div>Tobias Huber</div></div></body></html>