Help to understand PPK processing

Hi i new and i need help to understand and learn about PKK
How does it work? Base records data independent of the Rover equipment (UAV) and this records data of its trajectory.
What data does the Base equipment record?
What data does the Rover equipment record?
How does the Base data correct Rover data?
occupying the module reach ms + and reach rs +, what type of coordinates are occupied? WGS84?
Someone can share real data to process in RTKLIB to understand the process and practice
I have only made flights with correction from GCPs and I want to understand the PPK mode to see the convenience.

Greetings and thanks for the help you can give me

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Hi,

Hi i new and i need help to understand and learn about PKK

I guess there is plenty information in the documents and even more inside this thing called internet. You will have to read it youreself, I don’t think there is anyone who will read it to you. If there are specific questions left people will be happy to answer them.

You might watch these videos:

How does it work? Base records data independent of the Rover equipment (UAV) and this records data of its trajectory.

Both the base and the rover record the same gnss raw data on their individual position.

What data does the Base equipment record?
What data does the Rover equipment record?

Data on the characteristics of the wave the different satellites are transmitting.

How does the Base data correct Rover data?

The base does not correct the rover but provides information how to solve a equation to determine the position of the rover. You can read that inside this internet as mentioned above.

occupying the module reach ms + and reach rs +, what type of coordinates are occupied? WGS84?

I guess you need to get clear what is WGS84, coordinates and ellipsoids. Anyhow, in PKK it is not Reach but RTKLIB which handels all that stuff. You can see that if you read the docs or open the programm.

Someone can share real data to process in RTKLIB to understand the process and practice

Sorry, I can’t help you with that, @emlid might.

I have only made flights with correction from GCPs and I want to understand the PPK mode to see the convenience.

Depending on the quality expectations you have, you can skip GCPs since you know the position where the camera was when the picture was taken with high accuracy (<20 cm). For very high quality I personally still see deviations from the GCPs, but I hope I get better resulty when using lever arm correction.

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In the beginning of the year I myself was where you are now. Search the forum here, use google, look up words and phrases you don’t understand (there will be a lot of these, if you’re not from the industry, been there, done that).

I would suggest starting out with the Emlid documentation. It gives a really good starting-point, also when it comes to postprocessing, https://docs.emlid.com/reachrs/common/tutorials/ppk-introduction/

Thanks for the answers, I started reading about PPK only 4 days ago, I found something about the algorithm but it is not explained in simple words that it performs, the idea that I have is that the Base takes a data of its position in a certain time according to the configuration that is programmed, takes this same point all the time, this physical location is the same but the data is not the same, this difference between the original point or known control and the data that is taken every second for example, to its Once the Rover takes a data from different points in a certain time, then I believe that the software compares the points taken at the same time by the Base and the Rover, assuming that if the point of the base moved 10 centimeters from the point original at 90 degrees, the point taken by the rover at the same time should be 10 centimeters to 180 degrees, this is what I assume by the basic gps knowledge that I have, the forum or website only explain that real post a correction processing with the algorithm, maybe this is not the correct way to process the data and that is why I wrote this post.
I hope you can verify this idea that I have.
and since I do not have the equipment at this moment I can not generate real files and for that reason I would like to see files to test what I think, files that work well, because the forums only have files with problems which generate errors, this to practice and understand the PPK correction process.

I can hardly imagine that you can understand the process without understanding the formulas. But I don’t think that is a problem since I guess you don’t want to make research about PPK but work with a GPS device to get a accurate position.

I would concentrate on getting good data and developping a good workflow and than keep on doing what you really want do to. Life is short and there is only one, so you do not have the time to do everything but should concentrate on the thing you really want to do.

I think a very basic explanation on RTK/PPK is something like this:

Other than simple GPS it does not work with the information pattern which is transferred from the satellites but with the characteristics of the wave. Basically this wave can go up and down a specific number of times until it reaches the receiver. Each up an down equals some centimeters of distance. If you can tell the number of times the wave went up and down, you know your position.

The magic is to solve the equation which tells you the unknown times the wave went up and down. Since the base knows its own position, it can solve the other unknowns in this equation and then tell the rover how to solve the equation.

Hi @Daniel_Veas_Contrera,

You can try to process these logs:

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Hi, thank you
search too much for data

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