Electronics World articles Popular Electronics articles QST articles Radio & TV News articles Radio-Craft articles Radio-Electronics articles Short Wave Craft articles Wireless World articles Google Search of RF Cafe website Sitemap Electronics Equations Mathematics Equations Equations physics Manufacturers & distributors Engineer Jobs LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering magazine articles Engineering software Engineering smorgasbord RF Cafe Archives RF Cascade Workbook 2018 RF Symbols for Visio - Word Advertising RF Cafe Forums Magazine USAF Radr Shop Sponsor RF Cafe RF Electronics Symbols for Visio RF Electronics Symbols for Office Word RF Electronics Stencils for Visio Thank you for visiting RF Cafe!
Triad RF Systems Amplifiers - RF Cafe
withwave microwave devices - RF Cafe
 

About RF Cafe

Kirt Blattenberger - RF Cafe Webmaster

Copyright: 1996 - 2024

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 World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a nice lady's voice announced "You've Got Mail" when a new message arrived...

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

RF Superstore (RF Components) - RF Cafe

Impact of Noise Figure on Phase Noise - RF Cafe Forums

RF Cafe Forums closed its virtual doors in 2012 mainly due to other social media platforms dominating public commenting venues. RF Cafe Forums began sometime around August of 2003 and was quite well-attended for many years. By 2010, Facebook and Twitter were overwhelmingly dominating online personal interaction, and RF Cafe Forums activity dropped off precipitously. Regardless, there are still lots of great posts in the archive that ware worth looking at. Below are the old forum threads, including responses to the original posts.

-- Amateur Radio

-- Anecdotes, Gripes, & Humor

-- Antennas

-- CAE, CAD, & Software

-- Circuits & Components

-- Employment & Interviews

-- Miscellany

-- Swap Shop

-- Systems

-- Test & Measurement

-- Webmaster

crg
 Post subject: Impact of Noise Figure on Phase Noise
Posted: Fri Jul 22, 2005 3:03 pm 
Lets say you have a signal at a known frequency with a known amount of phase noise, and you pass the signal through a fixed attenuator, is there a way to calculate/estimate what impact the attenuation has on the phase noise of the output signal?

 
  
 
Kirt Blattenberger
 Post subject:
Posted: Sun Jul 24, 2005 11:30 am 
 
Site Admin
User avatar

Joined: Sun Aug 03, 2003 2:02 pm

Posts: 653

Location: Erie, PA

Greetings crg:

My guess is that the effect of the attenuator on phase noise would be similar to the intended signal and noise. You would need to perform a cascade analysis for the path where the phase noise is first injected and treat that component of the total signal as a separate signal that is summed with the intended signal.

The discrete phase noise component would be attenuated by an amount equal to the total Gain in the path from the phase noise injection point and the continuous phase noise component would be subject to the total Gain and Noise Figure.

If the phase noise is present on the signal at the system input, then it is treated to the same effects as the rest of the intended signal and noise.

If it is injected in an LO at a mixer, then the phase noise component is determined by a separate cascade comprised by the path the LO signal takes.

In the last case, for a real system the summation of the two components [(intended signal + noise] + [LO + phase noise)] would be a point-by-point vector addition, so a simple scalar summing could produce erroneous results.

Any comments by others?

_________________

- Kirt Blattenberger :smt024

RF Cafe Progenitor & Webmaster

Posted  11/12/2012

RF Cafe Sponsors
Berkeley Nucleonics Phase Noise Testing Seminar - RF Cafe

Please Support RF Cafe by purchasing my  ridiculously low−priced products, all of which I created.

These Are Available for Free