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 LinkedIn Crosswords Engineering Humor Kirt's Cogitations RF Engineering Quizzes Notable Quotes Calculators Education Engineering Magazine Articles Engineering software RF Cafe Archives Magazine Sponsor RF Cafe Sponsor Links Saturday Evening Post NEETS EW Radar Handbook Microwave Museum About RF Cafe Aegis Power Systems Alliance Test Equipment Centric RF Empower RF ISOTEC Reactel RF Connector Technology San Francisco Circuits Anritsu Amplifier Solutions Anatech Electronics Axiom Test Equipment Conduct RF Copper Mountain Technologies Exodus Advanced Communications Innovative Power Products KR Filters LadyBug Technologies Rigol TotalTemp Technologies Werbel Microwave Windfreak Technologies Wireless Telecom Group Withwave RF Cafe Software Resources Vintage Magazines RF Cafe Software WhoIs entry for RF Cafe.com Thank you for visiting RF Cafe!
ConductRF Phased Matched RF Cables - RF Cafe

Innovative Power Products Passive RF Products - RF Cafe

Crane Aerospace Electronics Microwave Solutions: Space Qualified Passive Products

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

RF Cascade Workbook for Excel

RF & Electronics Symbols for Visio

RF & Electronics Symbols for Office

RF & Electronics Stencils for Visio

RF Workbench

T-Shirts, Mugs, Cups, Ball Caps, Mouse Pads

These Are Available for Free

Espresso Engineering Workbook™

Smith Chart™ for Excel

Holzsworth

Filter Equivalent Noise Bandwidth

A filter's equivalent noise bandwidth (EqNBW) is the bandwidth that an ideal filter (infinite rejection in the stopband) of the same bandwidth would have. EqNBW is calculated by integrating the total available noise power under the response curve from 0 Hz to infinity Hz. In practice, integration only needs to be carried out to about the point of thermal noise. The steeper the filter skirts (higher order), the narrower the range of integration needed to get an acceptable approximation. Integration needs to be done in linear terms of power (mW, W, etc.) rather than in dB.

The values in the following table are for normalized lowpass filter functions with infinite Q and exact conformance to design equations. If you need a better estimation than what is presented here, then a sophisticated system simulator is necessary.

Butterworth

(fco = 3 dB)

Chebyshev

(fco = ripple)

Bessel

(fco = 3 dB)

Order EqNBW
1 1.5708
2 1.1107
3 1.0472
4 1.0262
5 1.0166
6 1.0115
7 1.0084
8 1.0065
9 1.0051
10 1.0041
Ripple 0.01 dB 0.1 dB 0.25 dB 0.5 dB 1.0 dB
Order
2 3.6672 2.1444 1.7449 1.4889 1.2532
3 1.9642 1.4418 1.2825 1.1666 1.0411
4 1.5039 1.2326 1.1405 1.0656 0.9735
5 1.3114 1.1417 1.0780 1.0208 0.9433
6 1.2120 1.0937 1.0448 0.9970 0.9272
7 1.1537 1.0653 1.0251 0.9828 0.9175
8 1.1166 1.0471 1.0125 0.9736 0.91133
9 1.0914 1.0347 1.0038 0.9674 0.9071
10 1.0736 1.0258 0.9977 0.9629 0.9041
Order EqNBW
1 1.57
2 1.56
3 1.08
4 1.04
5 1.04
6 1.04

Reference: Filter Design, by Steve Winder

Holzsworth
RF Electronics Shapes, Stencils for Office, Visio by RF Cafe

RF Cascade Workbook 2018 by RF Cafe

KR Electronics (RF Filters) - RF Cafe