I was thinking about ways to improve results from a session in a poor location.
If I identified the times when a satellite was received (by reflection) but not direct line of sight because of buildings, and took out that data from the RINEX, it should improve the results.
I would need a complex elevation mask, which probably means a lot of manual work, as I don't think I have a tool to do it..
It would be a lot easier to zero out the SNR than to remove the data from the file, if that would tell OPUS to de-weight it..
I would need a complex elevation mask, which probably means a lot of manual work, as I don't think I have a tool to do it..
I believe the elevation mask is only a means to filter out the radio signals from satellites whose orbital positions are below the mask. GPS surveying equipment is not able to determine the elevations or directions of the radio signals received, so a complex elevation mask would be of little use, unless you were wanting to block out a satellite because it is behind a tall building or other obstruction.
block out a satellite because it is behind a tall building or other obstruction.
That was the idea. Just because it is behind an obstruction doesn't always prevent the receiver from getting the signal on a rebound and coming up with the wrong pseudorange.
Since most software masks on calculated elevation versus a single elevation value, if I want that to be different in different directions I'd have to figure out how to disable certain satellites at certain times and modify the RINEX myself.
At this point, I'm just curious about the possibility, which would probably be too much work.
No matter how much you want it, you cannot get old equipment to equal the performance of the latest and greatest. Live within the limitations you have and put your extraordinary efforts elsewhere.
Paul in PA
I never particularly heard a statement that would answer that question, but it is my understanding that OPUS looks at the SNR and if it is not up to acceptable limits I believe it just excludes that data. So in affect a low signal to noise ratio means more data would be excluded which is giving that particular satellite significantly less weight.
Paul in PA