Feed in a known power, note down the digital power, repeat for another known power.
You'll get three input power->digital power mappings.
Now, assume the power transfer function is a linear one:
With the two
measurements you can simply deduce the slope 
of the
above function; simple math, subtract the equations:
and find
and the
offset 
. Repeat with a few other known powers to make sure you're in the linear region.
Whatever you do, never feed in more than -15dBm into your device!
Best regards,
Marcus
On 21.03.2016 23:05, Fikrat Al-Kazimi
wrote:
Hi guys,
I hope you're all doing well.
I'm been searching a lot and I read that if I want to measure the absolute power ( in W or dBm ) using the usrp_spectrum_sense.py, then I must calibrate the USRP by injecting a signal of known physical power.
Can someone please walk me through the calibration steps? How can I accomplish this and what do I edit in the code after calibration is complete to help me sense the absolute power instead of power_dB?
Thank you for your help!
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