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I got below float numbers after soapy_power -f 80M:100M -B 1000 --output a --format rtl_power:

['2022-02-01', ' 04:08:40', ' 80000000.0', ' 92000000.0', ' 1000.0', ' 16320', ' -124.55009', ' -123.28683', ' -119.09669', ' -122.33046', ' -118.7041', ' -115.49231', ' -117.409424', ' -117.928085', ' -123.43306', ' -119.76097', ' -121.75209', ' -119.694305', ' -115.521576', ...... ' -120.52822', ' -119.66289', ' -124.09914', ' -125.481125\n']

What's the meaning of those negative float number?

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These are decibels relative to some arbitrary full-scale value. Hence, negative values denote a power smaller than that reference.

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  • $\begingroup$ @I try to analyze those data.How to identify the frequency of ' -123.28683'? $\endgroup$
    – kittygirl
    Commented Feb 2, 2022 at 1:49
  • $\begingroup$ you yourself have set the output format, so I guess you know how it is defined. I'm not aware what --format rtl_power does, but you had some reason to specify it, so I guess you will have to answer this. $\endgroup$
    – Marcus Müller
    Commented Feb 2, 2022 at 10:14
  • $\begingroup$ Yes, this is the more correct answer. My answer is probably wrong. These values are centred around your chosen frequency range and represent relative power from the centre of the range (even if that range is a single point). The example on the GitHub shows the exact same results. But, to be sure, you can ask here: github.com/xmikos/soapy_power/issues Also check out this tutorial: docs.deepwavedigital.com/Tutorials/5_simple-soapy.html $\endgroup$
    – user21417
    Commented Feb 2, 2022 at 13:29

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