no noise figure analyzer how to measure a new LNA NF? - RF Cafe Forums

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LELE FIR

Post subject: no noise figure analyzer how to measure a new LNA NF?

Posted: Tue Aug 21, 2007 10:19 am

Lieutenant

Joined: Tue Aug 21, 2007 9:43 am
Posts: 3
Location: shanghai

I have design a ATF-54143 LNA
but have no noise figure analyzer
just a HP8563E Spectrum and a signal generator and vector analyzer
so I can measure S21 and S12 S11 and P1dB

BUT I can not measure NF of LNA .
Spectrum have so more error when connect with generator.

HOW can I measure a NF of LNA without noise figure analyzer

thank you .

RFDave

Post subject:

Posted: Tue Aug 21, 2007 9:50 pm

Captain

Joined: Sat Apr 22, 2006 11:14 pm
Posts: 20

You need a calibrated noise source to do a Y-Factor measurement. Agilent has a good app note at http://cp.literature.agilent.com/litweb ... -3706E.pdf

App Note 57-1 is also a good reference.

Dave

LELE FIR

Post subject:

Posted: Wed Aug 22, 2007 8:37 am

Lieutenant

Joined: Tue Aug 21, 2007 9:43 am
Posts: 3
Location: shanghai

THANK you

I known these 3 ways to measue NF .

1 use noise figure analyzer ,(I have not)

2 use spectrum to calculate NF.GAIN measurement ( our company's spectrum have so many errors)

3 use Y-Factor measurement (I have not noise source).

oh, no way

RFDave

Post subject:

Posted: Thu Aug 23, 2007 9:54 pm

Captain

Joined: Sat Apr 22, 2006 11:14 pm
Posts: 20

The Noise figure meter simply automates the Y-factor measurement. You really need a noise source to do this. It's been a long time since I purchased a noise source, but google is your friend here. The Amateur radio community has build up noise sources from Noise diodes and Zener diodes, so you could probably DIY a noise source if you have to.

Dave
www.keystoneradio.com

Posted 11/12/2012

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