Thank you for visiting RF Cafe! Electronics World Cover,TOC,and list of posted Popular Electronics articles QST Radio & TV News Radio-Craft Radio-Electronics Short Wave Craft Wireless World About RF Cafe RF Cafe Homepage RF Cafe in Morse Code Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs Twitter LinkedIn Crosswords Engineering Humor Kirt's Cogitations Engineering Event Calendar RF Engineering Quizzes AN/MPN-14 Radar 5CCG Notable Quotes App Notes Calculators Education Magazines Software,T-Shirts,Coffee Mugs Articles - submitted by RF Cafe visitors Simulators Technical Writings RF Cafe Archives Test Notes Wireless System Designer RF Stencils for Visio Shapes for Word Search RF Cafe Sitemap Advertising Facebook RF Cafe Forums RF Cafe Homepage Thank you for visiting RF Cafe!

Measuring The Noise Figure of WLAN Receiver RF Front-End - RF Cafe Forums

The original RF Cafe Forums were shut down in late 2012 due to maintenance issues. Original posts:

Amateur Radio | Antennas | Circuits & Components | Systems | Test & Measurement

 Post subject: measuring The Noise Figure of WLAN Receiver RF Front-end
Posted: Thu Jan 21, 2010 7:31 am 
User avatar

Joined: Wed Aug 16, 2006 8:20 am
Posts: 28
Location: India

I want to measure the Noise Figure of the RF Front-end (Switch+LNA+Diplexer) for a WLAN receiver implemented using Discrete components.

I don't have a Noise source and Noise Figure meter to chatracterize the Noise Figure of this assembly. I was thinking of trying the following approach.

1. Since I don't have a vector signal generator, I will use a WLAN transmitter that I designed. Attenuate the output power to -60dBm (burst power). Feed this signal to a Vector Signal Analyzer and measure the EVM. Let us call the EVMin

2. Remove the VSA and connect the RF Receiver Front-end. This will feed the Transmitted signal at the antenna port of the Receiver. Now at the other end of the receiver chain connect the VSA and record the EVM. Let us say that this is EVMout.

3. Can I assume that the EVM will be proportional to the SNR at low input power levels. if yes, then can I use the difference between EVMin and EVMout as an estimate of the Receiver RF Front-end Noise Figure.

I will be trying this out in the LAB. If anyone finds any fault in this method thebn please share your thoughts.

Ashish Bondia

Ashish Bondia,
Design Engineer- RF

Posted  11/12/2012

RF Cafe Software

   Wireless System Designer - RF Cafe
Wireless System Designer

RF & EE Symbols Word
RF Stencils for Visio
Calculator Workbook
RF Workbench
Smith Chartâ„¢ for Visio
Smith Chartâ„¢ for Excel

About RF Cafe

Kirt Blattenberger - RF Cafe WebmasterCopyright
1996 - 2022
Kirt Blattenberger,

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The Internet was still largely an unknown entity at the time and not much was available in the form of WYSIWYG ...

All trademarks, copyrights, patents, and other rights of ownership to images and text used on the RF Cafe website are hereby acknowledged.

My Hobby Website:

Try Using SEARCH
to Find What You Need. 
There are 1,000s of Pages Indexed on RF Cafe !