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I'm using Google's MATLAB code to analyze raw gnss measurement made with gnsslogger android app. In plots, there is one in particular that I don't understand the meaning, which is "Common frequency offset" plot. At first I thought it was how much the "Common bias clock offset" was varying, but as you can see, when this latter gets a spike, the "Common frequency offset" doesn't change much. So what is the meaning? I searched everywhere but haven't found anyhting. Has Doppler effect something to do with it?

enter image description here $$ \mathbf{x} \text{ axis is time (seconds)}$$

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    $\begingroup$ @uhoh they are seconds $\endgroup$
    – allexj
    Apr 20 at 8:58

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UPDATE: I'm giving up, I can't find much in web. But this is what I think this plot is: I THINK it's how quickly per second the rx clock drifts, but: if for example I put a big delay in spoofing in Matlab code, then I have an incredible peak in "common bias block" plot, BUT the "common freq offset" DOESN'T change a thing, you don't notice anything. so MAYBE this plot is performed post bias estimation so after position calculation https://developer.android.com/develop/sensors-and-location/sensors/gnss#interactive-plots maybe we can say it's "aseptic" to the delays and therefore it actually tells me the real user clock drift

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    $\begingroup$ Hi @allexj I suggest leave the question open and remove your "I'm giving up answer". It's obvious from the Up votes others' think it's a good question. (I don't understand the question so I can't help.) Some questions stay around for a long time until someone realises they know the answer. $\endgroup$
    – Galerita
    Apr 21 at 9:30

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