I am processing rtl_fm output (in time domain), extracting Manchester encoded bits. I can detect preamble and, therefore, decode the message which follows the preamble. This is how my signal looks like (here I have 2 messages, the rest is noise):
And this one of the messages zoomed in:
Now I want to know how strong was the signal that I've just decoded. I know what is the average amplitude for my symbols: "1" is 2900 and "0" is 1500 (for the amplitude range of -32768 .. 32767). Is it possible to know the signal strength in dB in this case?