Post subject: Noise figure measurements Posted: Thu Mar
19, 2009 2:56 am
Joined: Sun Nov 02, 2008
My question is on sub 1 dB noise figure
measurements. Although I am using a low ENR source and an industry
standard noise figure analyzer, I get the impression that the noise
figure readings are consistently a little on the high side (0.2-0.3
dB higher) on the low noise amplifiers that I am measuring. Is there
an accurate way to cross check the measurements that I am making?
The instrument noise figure at the frequency of measurement is about
8.5 dB. Does one have to use a preamplifier to get more accurate
Post subject: Re: Noise
figure measurementsPosted: Sat Mar 21, 2009 6:32 am
Joined: Fri Feb 17, 2006 12:07 pm
I had a look at graph 6.1 of Agilent's
App Note 57-2 "Noise Figure Measurement Accuracy". It estimates
around 0.3dB error when using an analyzer with an 8.5dB NF.
might expect an error of around 0.2dB if you place a good 2dB NF
pre-amp in front of the analyzer.
bottom, life is all about
Sucking in and blowing out.
Post subject: Re: Noise figure measurementsPosted:
Sat Mar 21, 2009 3:55 pm
Jun 27, 2005 2:02 pm
can do the following:
1. Compare the measurements between
different DUT's and get a insight on the error magnitude.
Use another unit of the same Noise Figure Analyzer which you currently
use and see if you get the same size of error - then most probably
it is a measurement error of the Analyzer.
3. Better not to
use another preamplifier, because then you add another error factors
to your measurement setup (Gain and NF).