LNA measurements using only network analyzer

[carbon9]

lna measurements

Hello,

I have implemented a LNA using Sirenza's SBB-5089 MMIC on FR4 board. I have access to a network analyzer in the University lab containing HP 5071 network analyzer. I wnat to measure the LNAs noise figure using ONLY network analyzer. Is it possible?

Thanks

 

[Mazz]

noise figure measurement using network analyzer

I don't think so.
VNA is used to small signal response of circuits. It uses a sweeped CW signal and detectors to evaluate S parameters.
Noise figure is measured with a good accuracy with a noise source and Y-factor method, so you will need a receiver (typically a spectrum analizer or a dedicated instrument) to do it.
I hope it can help.
Mazz

 

[khouly]

network lna

some VANs of anrtisu have noise figure measuetns ,

but if u want to measure the NF use NF meter of agilent
so ur VNA is not enough

khouly

 

[7rots51]

measuring lna application note

what is the price of NF meter( from several vendors)?

 

[khouly]

lna network measurement

check
http://www.home.agilent.com/agilent/product.jspx?nid=-536902736.536880065.00&cc=US&lc=eng

khouly

 

[7rots51]

spf-5043z

SBB-5089 MMIC have high NF ,it is not good for LNA.Use SPF-5043Z with NF=0.8dB and freq=100-4000MhZ,in/out 50 ohm matched!

It is 28K$! Is there any low cost NF Meter (about 5K$)?

 

[khouly]

lna measure

5 K Noise figure meter , i doubt it

u can search for used items , but new one , it will be hard

khouly

 

[carbon9]

lna vna

Thanks for all replies.

I will now search for a cheap NF meter.

Thanks

 

[Mazz]

lna measurement

If you have a good spectrum analyzer, you can "build" your own NF meter buying only the noise source and a low noise preamplifier.
As NF meter uses the Y factor method, based on high temp/low temp noise source, you can manually measure it (or implement a software in Labview, for example).
See agilent application notes for details, if interested.
Mazz

 

[sergio mariotti]

measurements with a network analyzer

Hello,

I have implemented a LNA using Sirenza's SBB-5089 MMIC on FR4 board. I have access to a network analyzer in the University lab containing HP 5071 network analyzer. I wnat to measure the LNAs noise figure using ONLY network analyzer. Is it possible?

Thanks

The answer is NO, IT'S NOT POSSIBLE.

but...if yuo have avaliable a noise generator
if your VNA may be switched in receiver mode
if your LNA has enough gain to mask the noise of VNA
the manual switching, noise measurement may be tryed, but this is a thinking speculation.
In any case, when measuring NF , the causes and sources of uncertainty are almost infinite.
My suggestion is if you have not a NFA and You cannot buy, the most cheaper way is to loan it for the period You plan to use.

 

[DeeLau]

pna-x using as spectrum analyzer

of course u can do it, with the newest high performance Agilent VNANA-X,

u can finish all the LNA measurements including the NF, IMD, harmonics,Gain

compression.

pls check www.agilent.com/find/pnax

 

[molidong]

lna measurements using network analyzer

Spectrum analyzer can measure LNA noise figure!

 

[SagSag]

measure lna design with network analyzer

you can measure the NF with a network.
1. connect the network for a S21 test.
2. connect the LNAs output to port 2.
3. meaure the noise level.
4. connect the LNA to DC.
5. measure the noise rise, it's G+NF, you know G so you can deduce NF.
6. if you don't see a noise rise it's becuse the network has a high NF, if that's the case connect a reference LNA between your DUT and the port.

you should also use a low RBW.

enjoy