GNSS live map - Planning best reception? or avoid a bad time

Not sure if this will help.
https://in-the-sky.org/satmap.php
The above linke,dos it show satelites Reach use?
Share links if you got any :slight_smile:
http://science.nasa.gov/iSat/?group=SMD

And another great sat planner. This one is my favourite
http://satpredictor2.deere.com/homePost

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web app:
http://www.taroz.net/GNSS-Radar.html

source code on github:

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Anybody notice difference from time to time, getting fix?
Ex.getting av fix one day and some time later at at same point, no fix?
Here`s screenshot from my current position.Any comments on this info?

I choose gps, galileo and glonass, i assume reach process and can use all these sats?



I was told to turn off the integer ambiguity resolution for GLONASS, and I assume that advice still stands. I know there was some talk of a new “fix and bump” mode for GLONASS ambiguity resolution, but I’m not sure if/when it might be implemented.

You can turn off the AR for GLONASS under advanced settings ReachView’s rover mode. For post-processing, you can do the same in the options menu of RTKPOST.exe

Also, if you have 5 GPS satellites showing, try with GPS only. If you get a fix, then add GLONASS and see what happens.

Great tip. I`ll for sure test this .

Yes, when logging over a long period of time, I see the fix coming and going, but it usually happens when the antenna is not in an ideal place (like rising terrain blocking part of the sky). With good sky view the fix stays the whole time (many many hours).

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All right :slight_smile: I see the level of degrees is set to 10 or 15 as default. Right here where i am testing i have obstacles and measured this to be up to 22 degrees. Should i switch place og try adjusting setting? . I got fix couple of times when moving around in a small spot so i think i am pretty close.
Yes i know about sats and what to expect. I`m just trying to find the minimum or worst condition so i know what to expect when doing live survey, so i dont wast time in an area where there is no hope.
Please share any experience.

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I would also like some advice on settings to improve my reception. I have upgraded my antennas and can get 6 to 8 satellites consistently over 45, but very rarely get a fix. I am working in open areas with no obstacles. The equipment that I am connecting to requires a DGPS signal although I don’t really need acuracy better than 15cm. What might be the effect of changing the ambiguity resolution, or the degrees under “advanced”? Or any other setting? BTW I only have access to GPS L1.

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@TB_RTK In your skyplot picture above, you have 5 gps satellites which are more than 30 degrees above the horizon. You could raise your elevation mask to something between 22 and 30. Depending on the situation, that may eliminate some multipath signals and get you a fix.


in the picture above, the terrain rises from bottom to top. The terrain at the top is blocking and reflecting, and the patch of trees just below the road is doing the same thing. The blue dots are the default .pos file from Reach using RFD900 radios (multipath errors - mostly floats and a couple fixes), and the yellow dots are after playing with different settings (mostly elevation mask) in RTKPOST (all fixes). The difference is about 33 meters between the two lines. Usually it is not that much (a meter or 2, or tens of centimeters), but this is the most exaggerated example I could find.

For example, this picture, or in the opposite case where a satellite that is below the terrain has a signal passing overhead and is reflecting off of something (trees/building) and then reaching the antenna and confusing your position.

Having a multi-frequency system, (L1/L2/L5, etc.) would help eliminate some of these problems, but they will also empty your wallet of many times more money than Reach does. Instead, it is better to spend time in getting experienced with RTKLIB and save money.

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Good point. Recap to see if i got things right.
Adjust lvl to 30 to reduce multipath which gives more accurate fix, but loses some accuracy by adding more values to DOP but this is a compromise. Multipath can give large deviation in fix and high DOP gives more inaccurat reading but fixes are closer together. So it all depends on the situasjon and what level of accuracy you need. Right?

Sounds right to me!

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What does these 3 settings apply to?

We can use Galileo?

You can read about the settings in the manual (in the docs folder in RTKLIB) or find the .pdf on GitHub here.

Not entirely sure, but I think the third one only applies for Fix-and-Hold mode?

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