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 Thank you for visiting RF Cafe!

IP3 Out of Band - 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


john
Post subject: IP3 out of band
Unread postPosted: Mon May 30, 2005 5:56 am

What is the method to mesure and calculate Input IP3 Out of band,
meaning 2 signal out of the IF filter caused IM3 inband.


Top


Guest
Post subject:
Unread postPosted: Mon May 30, 2005 5:34 pm

You know, I think you need to create your own method but what about this:

Measure input tones trough a broadband directionnal coupler,

Measure inband IMDs at the output,

Divide by the gain the IMD products as measured at the output

The ratio of what measured at the input and the products is some sort of IMD measure.


Top


Guest
Post subject: IP3 "out of band"
Unread postPosted: Tue May 31, 2005 11:26 am

Umm - It appears the question is poorly put.

IP3 is the (hypothetical) point where the power in the 3rd order IM distortion products is equal to the power in the desired output. If there is zero desired output (as there will be if your filters are adequate), then there cannot be an IP3 as usually defined.

The previous respondent hinted at this when he said that you'd get "some sort of IMD measure" with the process he outlined.

If this measurement is for meeting a requirement, then you need to get the specifier to clarify the intent and execution of tests for this spec.

Good Luck!


Top


Gus
Post subject:
Unread postPosted: Thu Jun 09, 2005 9:57 pm
Offline
Lieutenant

Joined: Thu Jun 09, 2005 9:50 pm
Posts: 1
I may be failing to understand your question.

Are you talking about two out of band signals mixing and causing an unwanted inband signal? If so, can't you inject two tones into the part of the circuit you are concerned about?


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
Webmaster:
Kirt Blattenberger,
 BSEE - KB3UON

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:
 AirplanesAndRockets.com

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

height-line