Hi
I have done GPS observations for 24 hours in Karachi Pakistan on a point to make it a control point. I have used Trimble SPS 855 for this static observation. I m facing two problems:
1. I have sent the data to OPUS, AUSPOS and RTX pp for post processing by using rapid ephimeris data. Now the problem is the results which I have received from OPUS and AUSPOS are almost similar with 5 - 10 cm difference but the results which I have received from RTX pp are 25 - 30 cm different.
Can anyone suggest me what is the problem and which result I should use.
2. Second I m using TBC for post processing the data. When I import the GPS file to TBC it automatically gives the position. Can anyone tell me how this position is calculated by TBC and what is the accuracy of this position.
Thanks in advance for the reply
Is RTX-PP using the same reference frame and epoch? The Indian subcontinent plate is one of the fastest moving I believe.
The position given in TBC will be autonomous until it is processed against another point.
Thanks for the reply. Coordinates settings for the OPUS and AUSPOS are the same as RTX PP. But there is remarkable difference in results as compared to OPUS and AUSPOS. However, results which I have received from OPUS and AUSPOS are almost similar
Have you tried a static PPP solution? You might need to wait a bit longer for better orbits and clocks, but in the long run it may be a better solution given your remoteness.
I don't think opus is the way to go.
For second opinion, I use NRC-PPP.
Natural Resources d'Canada precise point positioning. I've always received mm agreement using AUPOS and NRC-PPP.
Be sure to select ITRF. Beware, that won't mesh with provincial control.
https://webapp.geod.nrcan.gc.ca/geod/tools-outils/ppp.php