Filter Design Software

8/17/2019 Filter Design Software

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BAND-STOP FILTERS:

STRUCTURES:

DRAW CAPABILITY:

OTHER FEATURES:

Narrow-band quarter wave coupled lineWide-band quarter wave shunt stub

MicrostripShielded MicrostripStriplineSuspended SubstrateRound RodRods Coupled through

Septum or ApertureRectangular BarCoax (some Filters)

Printed filter drawings onthese pages were createddirectly from DXF files.

Accounts for unequal phasevelocities in micro-strip coupled linesand effects of frequency dispersion.

Creates HPGL or DXF file

W CAVE ON Filter DesignSoftware Parfil (Version 4.4) for Windows 95/98/NT/2000/XP/ME

(TM)

P.O.Box 2697, Escondido, CA 92033 TEL(760) 747-6922 FAX: (760) 747-5270

Parfil designs twenty different coupled line and

transmission line RF/microwave filter types. All of the parameters needed for filter construction arecomputed. The program accounts for "T", cross,via and step junction effects. Data is supplied intabular and graphical form for either English orMetric units. The filter types are:

Half wave - parallel coupled three coupling typesInterdigital - three types of input/output couplingCombline - two types of input output couplingHairpin - two types of input/output coupling

End coupled half waveQuarter wave shunt stubStepped Impedance

Shunt stub series lineShunt stub series line - Elliptic ResponseStepped Impedance

Gap coupled & open stubsQuarter wave shunt stub

BAND-PASS COUPLED LINE FILTERS:

BAND-PASS TRANSMISSION LINE FILTERS:

LOW-PASS TRANSMISSION LINE FILTERS:

HIGH-PASS TRANSMISSION LINE FILTERS:

Multiple Windows

Frequency Response

Plots

Designs Flat Group

Delay Filters

Frequency Response

Numerical Output

Filter Layout

Provided

Multiple Windows

Frequency ResponsePlots

Designs Flat GroupDelay Filters

Frequency ResponseNumerical Output

Filter LayoutProvided

SEPTUM


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BAND-STOP NARROW BAND

STEPPED IMPEDANCE BAND-PASS

INTERDIGITAL-OPEN INPUT/OUT

WIDE-BAND BAND-STOP

COAX LOW-PASS FILTER

SHUNT STUB BAND-PASS

TAPPED HALF WAVE PAR CPLD

TRANSFORMER HALF WAVE CPLD

LOW -PASS WITH ELLIPTIC ZEROS

GAP COUPLED HIGH-PASS

COMBLINE-SHORTED INPUT/OUT

HAIRPIN-PARALLEL CPLD IN/OUT

FILTER RESPONSE TYPES

TUNE CAPABILITY

TAPPED INPUT DESIGNS

VARY INTERNAL IMPEDANCE

PECIAL CAPABILITY forROUND ROD FILTERS

FREQUENCY RESPONSE

GRAPHICS CAPABILITY

Designs for Chebychev,Butterworth or Flat Group Delayresponses may be computed forany ripple and up to 17 sections.

A tuning screen may be accessedto permit changing circuit

parameters such as even and oddmode impedances or tap pointlocation.

Filter size may be reduced bytapping directly into the input/ output resonators rather thanusing parallel coupled line input/ output coupling.

This capability gives control overline widths or rod diameters.

Round rod Interdigital orCombline filters have additionaldesign choices as selecting equalrod diameters, choosing side wallor end wall distances.

Frequency response is computed

including loss, return loss, groupdelay or S-Parameters. Also, aTouchstone(R) S-Parameter filemay be created

Frequency response or thedrawing of the filter may bedisplayed on your monitor orplotted with a variety of printersor plotters or saved to a file. Youmay also save to a WindowsMetafile or create a bitmap on

your clipboard for pasting intoanother document such asMicrosoft Word.

The software supports all of theabove operating systems withtheir features. It includes theentire manual in the Helpcommand.

S

Windows95/98/NT/2000/XP/ME

(T)

MORE FILTERS WHICH MAY BE DESIGNED WITH Parfil

Vary Parameters andSee Results Immediately


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Low frequencyzero line.

Elliptic zero line

Tuning capacitors at endof lines.

Rod for high frequency ellipticzero.

Rod for low frequencyelliptic zero.

Also designscoupled rod filtersseparated by a septum

or aperture. Very usefulfor narrowband filter designs.

High freqzero line

HAIRPIN COUPLED LINE ELLIPTIC FILTER

MICROSTRIP COMBLINE ELLIPTIC FILTER

W CAVE ONWindows95/98/NT/2000/XP/ME

FilterDesignSoftware Elliptic (Vers. 4.3) for


Elliptic designs eight different coupled linefilters with Elliptic type frequency response. all of

the parameters needed for filter construction arecomputed. The program accounts for "T", cross,and step junction effects. Data is supplied in tabularand graphical form for either English or Metricunits. Two classes of filters having Elliptic-typeresponse characteristics may be designed. Flatgroup delay filters may be designed but withvarying performance depending on the type of filter.

First it designs four types of traditional Ellipticfilters illustrated in this page: the Half-WaveParallel Coupled, Interdigital, Combline andHairpin filters. For these filters, transmission zerosare formed by adding two additional lines to thearray of lines comprising the filter. Zeros may beselected to trap out any two frequencies. Whenplaced close to the filter passband edges a filtercharacteristic is created which has much steeperfilter rejection at the band edges. However, thereturn loss may be degraded.

Secondly it designs four types of filters known as

Cross-Coupled filters. These are designed bylightly capacitively coupling a line to a more distantline, e.g. coupling the first line to the fourth.

CONVENTIONAL ELLIPTIC

CROSS-COUPLED FILTERS

Multiple Windows

Frequeny Response Plots

Elliptic Zero 'Notches'

Frequency ResponseNumerical Output

Filter layout

Multiple Windows

Frequeny Response Plots

Elliptic Zero Notches

Frequency Response

Numerical Output

Filter layout


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ROUND ROD FILTERS

FREQUENCY RESPONSE

cross-coupling capacitanceswith interconnecting line.

Tuning capacitorsat end of lines.

COMBLINE CROSS-COUPLED FILTEREnd wall absent Cover not shownfor clarity. for clarity.

Line tappinginput rod.

Aperture in dividingwall coupling second

and second-to-last rods.

INTERDIGITAL CROSS-COUPLED FILTER

Round rod Interdigital or Combline filters haveadditional choices as selecting equal rod diameters,choosing side wall or end wall distances.Shown beloware examples of tapped interdigital and combline cross-coupled filters. Not shown are the parallel coupledinput/output coupling versions of the interdigital andcross-coupled filters.

Frequency respomse is computed for loss, return loss,group delay and S-Parameters.

.

Operation may be understood by considering a testsignal tuned in frequency from inside the filterpass-band into its stop-band. As the signalfrequency enters the stop-band its power leveldecreases until it equals the power level due to thepower through the capacitively coupled path.

When the power level of the normal filterattenuation path equals that of the capacitively

coupled path, if the phases are the same, thepowers will add and the resultant out-of-bandrejection will be degraded. If the two signals are180 degrees out-of-phase, the power levels willcancel. When cross coupling design is donecorrectly, the signals will cancel and anattenuation 'notch' or 'notches' will appear at theband edges. Note that as the signal frequency isfurther moved away from center frequency, thesignal from the cross-coupled path will be largerthan that of the normal filter path. Thus, far out-of-band attenuation will be less than that of theelliptic filter.

Advantages of Cross-Coupled filters: 1) permitdesign of smaller filters, 2) tapped filters may bebuilt with this approach since no additional zerolines are required next to the input and output lines,3) A deeper attenuation 'notch' can be achievedwith lossy filters than is possible with Ellipticfilters. Disadvantages of the Cross-Coupled Filtersare: 1) attenuation notches can only be located atthe pass-band skirts of the filter. Elliptic filters can

be designed with attenuation zeros anywhere infrequency. 2) stop band characteristics of the aregenerally poorer than Elliptic filters.

Microstrip Shielded MicrostripStripline Suspended SubstrateRound Rod Rectangular Bar

Accounts for unequal phase velocitiesin microstrip coupled lines andeffects of frequency dispersion.

Designs for Chebychev or Butterworthand Flat Group Delay responses maybe computed for any ripple and up to17 sections.

A tuning screen may be accessedto permit changing circuit parameterssuch as even and odd mode im-pedances or tap point location.

Advantages and Disadvantages of Cross-Coupled vs. Elliptic Filters.

STRUCTURES:

FILTER RESPONSE TYPES

TUNE CAPABILITY

Cross-Coupled InterdigitalFilter with Flat Group Delay

Vary Parameters andSee Results Immediately


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OFFSET STRIPLINE

BROADSIDE STRIPLINE

ROUND ROD STRUCTURE

consists of a singleconductor strip plated on a dielectric sheet suspended

between two groundplanes.

has a single conductorstrip oriented vertically with respect to thegroundplanes.

consists of a singlerod between two groundplanes. A dielectric materialmay fill the spaces.

LineComp analyzes or synthesizes eighteendifferent single and coupled line transmission

lines. Data is supplied in tabular and graphicalform for either English or Metric units. These are:

has a metalconductor strip plated on a dielectric sheet with abottom groundplane plated on the opposite side of the sheet as shown below. The analysis/synthesismay include a top shield if desired.

consists of a single conductor stripsandwiched between two dielectric sheets withgroundplanes plated on the opposite sides.

SHIELDED MICROSTRIP

STRIPLINE

W CAVE ONWindows95/98/NT/2000/XP/ME

Transmission Line Design SoftwareLineComp (Vers. 1.0) for


DIELECTRIC THICKNESS

METAL CONDUCTOR STRIP

METAL SHIELD OR COVER

METAL GROUNDPLANE

SHIELD DISTANCE

CONDUCTOR THICKNESS

STRIP WIDTH

GROUNDPLANE SPACING


TOP GROUNDPLANE

BOTTOM GROUNDPLANE

CONDUCTOR THICKNESS

STRIP WIDTH

DIELECTRIC THICKNESS


TOP GROUNDPLANE

BOTTOM GROUNDPLANE

GROUNDPLANE SPACING

STRIP WIDTH

SYNTHESIS/ANALYSIS MENUA typical Analysis/Synthesis windowis shown on the right. Input physicaland electrical parameters are enteredon the left of the menu. Computedparameters are on the right of thewindow. A drawing of the line to be

synthesized/analyzed is also shown.A top menu is provided for printing orsaving the window. You may alsoselect to include an optional title orchange the units to a variety of metricor English units.If desired you may plot the output dataover a range of values or print out anumerical tabulation over a range of values.

GROUNDPLANE SPACING


TOP GROUNDPLANE

BOTTOM GROUNDPLANE

CONDUCTOR THICKNESS

STRIP WIDTH

GROUNDPLANE SPACINGTOP GROUNDPLANE

BOTTOM GROUNDPLANE ROD DIAMETER


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MORE LINES ANALYZED/SYNTHESIZED BY LINECOMP

DIELECTRIC

THICKNESS

METAL GROUNDPLANE

SLOT WIDTH

GAP TO TOP

GROUND

DISTANCE TO

GROUNDPLANE

DIELECTRIC

THICKNESS

GROUNDPLANE

LINE WIDTH

COAX LINE INNER DIAMETER

METAL CONDUCTOR

COAX LINE OUTER DIAMETER

GUIDE

HEIGHT

GUIDE WIDTHTOP GROUNDPLANE

BOTTOM GROUND

DISTANCE

DIELECTRIC

THICKNESS

BOTTOM GROUNDPLANE

LINE WIDTH

TOP GROUND DISTANCE

DIELECTRIC

THICKNESSBOTTOM GROUNDPLANE

LINE THICKNESS

LINE WIDTH

TOP SHIELD DISTANCE

GAP

WAVEGUIDE SUSPENDED STRIPLINE COUPLED MICROSTRIP

GROUNDPLANE

SPACING

BOTTOMGROUNDPLANE

LINE WIDTH

TOP GROUNDPLANE

OFFSET SPACING

DIELECTRIC

GROUNDPLANESPACINGBOTTOM GROUNDPLANE

LINE THICKNESS

LINE WIDTH

TOP GROUNDPLANE

GAPDIELECTRIC

GROUNDPLANE

SPACINGBOTTOM GROUNDPLANE

LINE WIDTH

TOP GROUNDPLANE

SPACINGDIELECTRIC

GROUNDPLANE

SPACING

BOTTOM

GROUNDPLANE

ROD DIAMETERTOP GROUNDPLANE

SPACINGDIELECTRIC

SEPTUM

THICKNESS

SEPTUM

OPENING

GAP TO

TOP GROUND

DISTANCE TO

GROUNDPLANE

DIELECTRIC

THICKNESSGROUNDPLANE

LINE WIDTH

LINE SPACING

DIELECTRIC

THICKNESS

BOTTOM GROUNDPLANE

LINE THICKNESS

LINE WIDTHTOP SHIELD DISTANCE

GAP

DISTANCE TO

BOTTOM GROUND

COAX SLOTLINE COPLANAR LINE

COUPLED STRIPLINES COUPLED OFFSET LINES

COUPLED BROADSIDE LINES COUPLED RODS WITH SEPTUM

COUPLED COPLANAR LINES CPLD SUSPENDED STRIPLINES

DESIGN FEATURES Line Loss

Eff. Dielectric Const.

Help

PLotting

Accuracy

The analysis computesline loss and line Q forboth single and

coupled lines.

Effective dielectricconstant is computedfor single lines. Evenand odd mode effectivedielectric constants arecomputed for coupledlines.

The Help menu item

opens up the entiremanual for LineComp.

Once the line or linescharacteristics havebeen computed, theline impedance(s) maybe plotted or displayednumerically versus anyof the input parametersas shown to the right.

Generally within 1%.Where available, exactsolutions were used forthe analysis. Wherenot available, analysissuch as Finte Elementanalysis was done for alarge number of pointsand interpolated


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TRANSMISSION LINES in ProCAP

L-C FILTER SYNTHESIS

Transmission Line analysis and synthesis isincorporated into the program by easy menu access.When a transmission media is menu selected, thecircuit list automatically adds the selected media.Media types available are:

Single and multiple coupled microstrip lines.Single and multiple coupled striplines.Single and multiple coupled rods.single and multiple coupled suspended stripline.single and two coupled co-planar lines.single and two coupled offset striplines.single and two coupled broadside lines.

coaxwaveguide

Multiple coupled lines up to ten may be analyzed.This capability is particularly useful for filter designand analysis including diplexers when used with thecompanion program

L-C Filter synthesis is also done by easy menu accessfor Butterworth, Chebychev, and Bessel filters.

Parfil.

W CAVE ON Design & Analysis Software ProCAP (Version 1.0) for Windows 95/98/NT/2000/XP/ME

(TM)


ProCAP is a comprehensive general nodal

analysis program for analyzing circuits commonlyused by RF/Microwave engineers.

Complete Nodal Circuit Analysis.Multiple Coupled Line Analysis.Noise Analysis including Transistor.Noise Circles.Transducrer Input and Output Parameters.Monte Carlo Sensitivity Analysis.Optimization Capability.Tune Capability.Equation Capability.

Extensive Device Data Libraries.Many Output Plots and Numerical Lists.

Transmission Line Analysis and Synthesis.L-C Filter Synthesis.Matching a One-Port.

ANALYSIS CAPABILITIES OF ProCAP

SYNTHESIS CAPABILITIES OF ProCAP

ircuit Elements Window

ircuit List Window

Circuit Elements Window

Circuit List Window

Menu Bar

Tune Windows

Multiple Output

Windows

MarkerFrequencies andValues


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A typical menu for bandpassfilter design is shown to the rightof this page

Tuning a ciruit is done by placinga ? mark prior to the elementvalue. When the circuit isanalyzed, a tuning box appears atthe top of the screen for up toeight elements. For more thaneight elements a tuning windowmay be accessed for tuning moreelements than eight..

Two menus are available forplotting both two and three-portparameters. These include all of the S-Parameters, Gain/Loss,Noise Figure, Return Loss,VSWR, Phase, Group Delay andVoltage Gain

Parameters may be plotted usingeither a linear or a log frequencyscale. The log scale is especiallyuseful for Op-Amp analysis.

When a transistor is used withnoise parameters, noise circlesand transducer input and outputgain circles may be plotted.

Plots may be saved as metafilesor selected into the clipboard as a

bitmap

Numerical output listing may beobtained for most parameters asS-Parameters, Y, Z, ABCD, andImpedance parameters for one,two and three-ports.

TUNE CAPABILITY

PLOT CAPABILITY

NUMERICAL OUTPUTS

Log or Linear Scale

S-CIRCLES

SAVING PLOTS

ELEMENTS

OPTIMIZATION

More than 100 types of elements maybe selected for the widest variety of designs. Most of the elements, found

in other general analysis programssuch as Touchstone(R), are alsoprovided in

When an element has been selectedfor tuning using ?, it may also bevaried under circuit optimization.When the menu item is selecteda menu appears for definingoptimization items, their frequencyranges and weighting factors for

ProCAP

Opt

optimization. When optimizationis run, the program shows an errorat the bottom of the screen whichdecreases as the circuit isoptimized. When done, the plottedoutput and shows the finalperformance and updates theCircuit List.

The menu item is forsetting two or more parametersequal to another parameter or forintroducing an equation relatingparameters mathematically.

Colors for plots may be menuselected for any set of colors withwhite or black background.

A menu for Monte Carlo yieldanalysis may be selected. The

results show the possible variationin circuit performance for elementvariations. Ranges for elementvariations are menu selected.

menu allows selection of GHz, MHz, or KHz for Frequency.Length may be selected in inches,mils ,cm, or mm and SurfaceRoughness in microns ormicroinches.

EQUATE

COLORS

MONTE CARLO

UNITS

Equate

Units

INPUT

PORT 1

50 Ω

OUTPUT

PORT 2

50 Ω

OUTPUT

PORT 3

50 Ω

1.228 GHz FILTER

1.576 GHz FILTER

APPROX λ /4

TRANSFORMER

Diplexer S21, S11 S22, S31 & S33

Diplexer Design Example:Schematic Diagram

Documents

Filter Design Software