DGPS Post processing

I read the following(attached) article in a book and it says we can process the raw files from base and rover to get precise position even without an active wifi or radio connection between the receivers. Anyone with the steps to this procedure, i will be grateful.
Thank you!

Refer to Emlid DOCS here for starters.

I’m not sure if you mean real-time or Post-Processing.

Most of the discussions in this Community center around RTK Kinetic and Static real-time and post-processing. Real-time needs communications between Rover and Base. Post-Processing does not.

RTK processing is usually more accurate than DGPS , but needs at least L1 Carrier processing like Emlid.

Refs: Emlid FORUM, DOCS, GitHub RTKLIB

I’m using emlid reach modules, and I’m referring to post processing raw files.
As the base station sends correction to the rover in real time via a radio or wifi link, but is it possible if i get log files from base and rover in single mode without any connection, at the same time and post process these to get the precise position of either receiver as if they were connected with wifi or radio and i was getting a fix status.
Like manually calculating errors with base raw log files and applying it to rover log files.

Hi
Is this what you want?
https://docs.emlid.com/reach/common/tutorials/gps-post-processing/

Jim

Your question is a bit confusing I think. We normally speak of processing in two ways: real time processing (as in RTK) or post processing (as in PPK).

It seems that you are asking about a third way. Do you want to stream the log files from your base and rover to a third computer and do the processing there in real time?

If so, rtknavi.exe is the program you want to use. It won’t really do any better than RTK in ReachView, but you will have more control over the settings, and you can stream your raw logs into it.

The one disadvantage to real time processing is that you can’t process a combined solution (by going forward and backward in time). This is what makes rtkpost.exe give a little bit better results.

Can i get the steps to perform the process in highlighted text? It might help solve my problem.
Thanks

1.Start raw logging on base
2.Save correction data from a service like CORS ( in my country we use CPOS)
3.Both datasamples must be from the same timespan.

CORS is a Continuously Operating Reference Station, that is serviced and operated to give you e.g a refrencedata to postprocess or use as NTRIP for RTK.
There are many systems out there,and they basically do the same thing. Some you need to pay for, others are free.
If you dont have access to this kind of service, you can like me, use a known point and put one unit over known point and another over a unknown point. Raw logging on both and postprocess to gain absoulte coordinates for unknown point. Coordinates for known point is added into the processing part and takes it into account.

A bit short explanation, but hope this helps.

Sir, what u wrote,
"use a known point and put one unit over known point and another over a unknown point. Raw logging on both and postprocess to gain absolute coordinates for unknown point. Coordinates for known point is added into the processing part and takes it into account."
How to execute this process was my original question.
Now, if you can please provide me the steps in detail for this process, i will be more than thankful.

Its acutally well explained right here in the docs https://docs.emlid.com/reachrs/common/tutorials/gps-post-processing/
But change this:
-Kinematic mode to static (your doing a static survey, not a moving one)
-When you get to the part where it says “select base” and in stead of using “average base” , you use “Lat/Long/height” and fill in coordinates of your known point.

This should give you new absolute coordinates at the rover location.

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If I am understanding you correctly, you have a Rover log and a Base log, and you want to post-process only, as you do not have a real time link between the two? As long as they are within 100km or so, that is easy - Use the software available in the gps post processing docs as referenced earlier in this thread.

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Yes @Fenrir i successfully recorded the coordinates without a real time link(by post processing).
Massive thanks to @TB_RTK.
Thanks all for those positive replies.

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Hi everyone,

It’s been a long time since the last message was posted, but I have a small update for all of you :sunglasses:

We released our free software Emlid Studio, which contains a post-processing kinematics feature along with others. You can give it a try and share your feedback in the new thread!