Hi ,
I am measuring the NF of LNA(0.7dB, 22dB, 700M~800M) with N8973A.
However, I couldn't get the expected NF value. I only got the 1dB NF.
Are there any internal Pre-amp inside N8973A? I wonder if it is nessary to add one pre-amp behind the LNA to cut the noise from the mixer inside of N8973A.
I am measuring the NF of LNA(0.7dB, 22dB, 700M~800M) with N8973A.
However, I couldn't get the expected NF value. I only got the 1dB NF.
Are there any internal Pre-amp inside N8973A? I wonder if it is nessary to add one pre-amp behind the LNA to cut the noise from the mixer inside of N8973A.
There are other DUT characteristics that must be taken into account to come up with an overall uncertainty for your measurement. It is quite possible that you have a 0.5 dB of uncertainty for a 0.7 dB N.F. measurement that you’re trying to make.
There is an uncertainty calculator that should be used to see what the uncertainty for the measurement actually is. Go to http://www.agilent.com/find/nfu
Regards -