Advanced Design System 2001

Release Notes

August 2001

Notice

The information contained in this document is subject to change without notice.

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Copyright © 2001, Agilent Technologies. All Rights Reserved.

ii

ContentsDesign Environment ................................................................................................. 5Analog/RF User-defined Models .............................................................................. 6Agilent Ptolemy Simulation....................................................................................... 7

HDL Cosimulation............................................................................................... 9ISS Cosimulation ................................................................................................ 10Examples............................................................................................................ 11Models................................................................................................................ 13

Optimization/Yield Analysis ...................................................................................... 13Importing and Exporting ........................................................................................... 14Momentum................................................................................................................ 14Translators ................................................................................................................ 16

MDS and Series IV to ADS ................................................................................ 16SPICE................................................................................................................. 16

Design Libraries........................................................................................................ 17EDGE ................................................................................................................. 173GPP W-CDMA.................................................................................................. 18

Electronic Notebook ................................................................................................. 19Instrument Server ..................................................................................................... 20Printing/Plotting ........................................................................................................ 21Design Guides .......................................................................................................... 22DesignGuide Developer Studio ................................................................................ 23ValiFire...................................................................................................................... 24Documentation ......................................................................................................... 25

Online Access .................................................................................................... 25Vendor Library Components.......................................................................... 25Data Display .................................................................................................. 25Design Guides............................................................................................... 25MDS Design Translation ................................................................................ 26Instrument Server.......................................................................................... 26RFIC Dynamic Link........................................................................................ 26

Search ................................................................................................................ 26Errors and Omissions......................................................................................... 27

Installation ..................................................................................................... 27Analog/RF User-defined Models ................................................................... 27User’s Guide.................................................................................................. 27Series IV Design Translation ......................................................................... 28Expressions, Measurements, and Simulation Data Processing .................... 29Customization................................................................................................ 30Momentum..................................................................................................... 31

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DesignGuide Developer Studio ..................................................................... 32Design Guides............................................................................................... 32Circuit Components ....................................................................................... 33

iv

ADS 2001 Release NotesThis document describes known defects in Advanced Design System 2001 and,wherever possible, provides workarounds. It also identifies errors and omissions inthe ADS 2001 documentation. The information is grouped in categories.

Design EnvironmentDelay when saving files

A delay of up to 20 seconds may occur the first time you use the Save As commandin an ADS session. The delay occurs because the program checks for name conflictsbetween the design name and built-in component names. The length of the delay isbased on the number of libraries installed.

Design file corrupted on saving

If you run out of disk space while saving a design on UNIX, the design file may getcorrupted. The corrupted file may cause ADS to fail when you open the design. Toavoid this problem, make sure you have enough disk space before running ADS.

Design-related AEL files not automatically updated on saving

When you make changes to an item definition through the Design Parametersdialog box, those changes are not automatically saved on saving the design.

When you make changes in the Design Parameters dialog box, click the Save AELFile button before dismissing the dialog box.

Information on library_group is lost when design is copied

If you copy a design for which you have defined a library (the Library Name fieldin File > Design Parameters), the library information will be lost.

The workaround is to open the copied design, choose File > Design Parameters, andenter the desired library name in the Library Name field. Alternatively, you canmanually edit the AEL file to add the desired library name.

Invalid design names

Design names cannot be the same as the names of any built-in components.Because UNIX is case-sensitive, you are allowed (although we do not recommendit) to name designs after components as long as you change the capitalization. Thisis not allowed on the PC because the operating systems are case-insensitive.

Design Environment 5

An example worth noting is the commonly used temporary filename Test. This isthe name of a Signal Processing component and therefore is not allowed on eitherplatform with the capitalization shown. Using this name with differentcapitalization is valid on UNIX, but is invalid on the PC.

Moving ports to another layer (Layout)

You cannot use the Move To Layer (Edit > Move) command to move a port to adifferent layer. Instead, choose Edit > Component > Component Parameters, selectthe Port, select the layer parameter, and select the desired layer from thedrop-down list.

Unarchiving .zap files on UNIX with insufficient disk space

ADS may hang if you attempt to unarchive an archived (.zap) project on UNIX anddo not have sufficient disk space. This problem has been observed on HP-UX 10.20but may also occur on other operating systems.

Ensure that you have sufficient disk space before unarchiving a large project (alarge amount of RAM is also required). If necessary, try renaming the .zap file witha .z extension and use the unzip utility to decompress the project file.

Deactivated ground connected to named node prevents simulation

The design environment does not recognize a deactivated ground connected to anamed node as a valid condition and produces an error message that preventssimulation. The workaround is to delete the ground or break the connection (Edit> Move > Move & Disconnect) prior to simulating.

Analog/RF User-defined Models• To compile a user-defined model on the following platform, modify the variable

USER_LIBS, in the user.mak file, as shown next:

• IBM AIX 4.3

USER_LIBS = -llinker

• On PC only, if you compile and simulate, and need to compile again, beforerecompiling, from the Schematic window, choose Simulate > Stop and ReleaseSimulator.

6 Analog/RF User-defined Models

Agilent Ptolemy SimulationberMC, berMC4, and ErrVecMeas migration problem

If you migrated from 1.3 to 1.5 and installed the ADS 1.5 Service Pack 1, or if youare migrating directly from ADS 1.3 to ADS 2001, ignore this problem.

If you moved from ADS 1.3 to ADS 1.5 and did not install the ADS 1.5 ServicePack 1, please read this section to understand the problem and its workaround.

The components berMC, berMC4, and ErrVecMeas did not migrate properly fromADS 1.3 to 1.5.

To fix this problem, read the value of the component’s TimeUnit parameter inADS 1.3 and append it to the value of the SymbolTime parameter in ADS 1.5.

If the SymbolTime parameter is set by an expression, the expression must beenclosed in parentheses followed by the unit. For example, if SymbolTime was setto SymTime+X and the ADS 1.3 time unit was msec, then the SymbolTime shouldbe set to (SymTime+X) msec.

The same problem exists with the berMC and berMC4 DelayBound parameter.

SpectrumAnalyzer Sink containing CW tones may not display properly

The spectrum may not display properly if the input to the SpectrumAnalyzer sinkcontains CW tones and the NumFreqs parameter is set to a non-zero value.

TimeFile and TimedDataRead components cannot read multidimensional data

The TimeFile component (Obsolete Sinks library) or TimedDataRead component(Sinks library) cannot read multidimensional data. Attempting to do so will causea misleading error message to be displayed.

Multidimensional data can be generated using the OutFile or TimedDataWritecomponents when a ParamSweep or Optimization controller is used.

The workaround is to not use multidimensional data files with the TimeFile orTimedDataRead components.

Agilent Ptolemy Simulation 7

TimedSource component simulation problem when reading complex envelopesignal

The TimedSource component (Timed Sources library) will not simulate properly ifthe Expression parameter references an RF timed (complex envelope) signal by itsvariable or sink name used in the dataset named in the DataSet parameter.

The TimedSource component will not work with RF timed signals because it doesnot utilize the RF signal characterization frequency and propagates a zero valuefrequency instead. The component will work properly with baseband timedsignals.

The workaround is to only use the TimedSource component with baseband timedsignals. For complex envelope signals, use TimedToCx followed by CxToTimed,which specifies the Fc.

Using undefined parameter with NumericExpression or TimedExpressioncomponent causes simulation failure

The simulator will fail if an undefined variable or equation is specified for theExpression parameter in the NumericExpression component (Numeric Sourceslibrary) or TimedExpression component (Timed Sources library).

Variables and equations are specified in a VAR component. Variables may also bedefined as design parameters (see the Parameters tab of the Design Parametersdialog box).

The workaround is to use only defined variables and equations.

Bus support

• Ptolemy subnetworks do not support iterated ports. The workaround for this isto connect a Bus component (from the Numeric Control palette) to the port andspecify the bus width for the BusWidth parameter.

• There is no way to output a bus as a vector to the dataset. You can use aniterated instance of a sink to output the individual values of each bus wire.

Cosimulation involving designs with different time steps fails (Simulation.6813)

Any cosimulation of a DSP network with multiple A/RF subnetworks where two ormore of the A/RF subnetworks are simulated with different time steps will fail.There is no workaround.

8 Agilent Ptolemy Simulation

HDL Cosimulation

Real ports must be initialized for some ModelSim versions for VHDL entities

In a VHDL entity, the real ports must be initialized for certain versions ofModelSim SE (such as version 5.4d) or the ModelSim will fail with an out-of-rangeerror.

Stray processes need to be terminated manually

• On Windows platforms, if an HDL cosimulation is interrupted or it errors out,stray processes may continue (and tie up the license).

• On all platforms, if any other component (non-HdlCosim component) causes aruntime error while simulating a design containing an HdlCosim componentand the ADS simulation stops, the HDL simulator may still be running (andtying up the license).

The workaround for both of these problems is to terminate the stray processesmanually. The processes that may need to be terminated are

vlm.exe, vsim.exe, vish.exe (for ModelSim®), and verilog.exe (for VerilogXL®)

You may also have to terminate hpeesofsim.exe.

Custom HdlCosim components no longer supported

Custom HdlCosim components created using the ADS model builder are no longersupported.

Parameter values of HdlCosim components may require updating

Because of changes made to the HdlCosim component parameters in ADS 2001,parameter values of HdlCosim components in your ADS 1.5 designs may need tobe re-entered.

Agilent Ptolemy Simulation 9

ISS Cosimulation

Data types smaller than four bytes cause error messages

Error messages will occur if data types less than 4 bytes in size are used with theTI DSP C54x. Avoid using the data types char, uchar, double, long double, float,int, uint, long, ulong short, and ushort.

DSP target limitations on setup

A DSP target should be specified using the TI CCStudio Setup tool. Only one DSPtarget can be specified, and it is limited to the TMS320C6x/TMS320C54xsimulators. (Hardware boards such as DSK or EVM cannot be used as the DSPtarget.)

• If you specify more than one target, the Parallel Debug Manager will openduring cosimulation and the cosimulation will fail.

• If you do not specify a DSP target during setup, a dialog box will pop up duringcosimulation and prompt you to select a target DSP board or simulator. You willthen have to select a configuration and double-click the TI CCStudio icon orrestart TI CCStudio.

Environment variable required for TI CCStudio 2.0

If performing ISSCOSIM with TI CCStudio 2.0, without creating the appropriateenvironment variable first, the simulation will fail and the error message willindicate it is an installation problem. The workaround is to create an environmentvariable, TI_DIR, and set it to the CCStudio installation directory, typically C:\ti.

Incorrect path in example designs

The designs in the example project /examples/TICCStudioCosim/isscosim_prjcontain an incorrect setting for the Program parameter of the TICCStudioCosimcomponent.

In these designs/instances, the parameter is set incorrectly:

• fir_xdas.dsn (T1), Viterbi.dsn (T1), addsub.dsn (T1)

In this design/instance, the parameter is not set at all:

• addsub.dsn (T2)

The Program parameter for all these instances should be set to:

$HPEESOF_DIR/examples/TICCStudioCosim/isscosim_prj/<design_name>/...

10 Agilent Ptolemy Simulation

Examples

Simulation of testTxRx_SML.dsn fails

Simulation of the design Examples > Timed > TxRx_Subsystem_prj >testTxRx_SML.dsn will fail in ADS 2001. This failure occurs in any DSP networkthat cosimulates with multiple A/RF subnetworks where two or more of the A/RFsubnetworks are simulated with different time steps. There is no workaround.

Settings for Optim controller in example design must be changed

The following example designs contain Optim controller components for whichseveral options are deselected that are required to produce simulation results:

Examples > Tutorial > dspopt_prj > simpleopt1.dsn and simpleopt2.dsn

Examples > Training > DSP_Optimization > simpleopt1.dsn

For these designs, edit the Optim controller components as follows:

• On the OptGoal tab, make sure the Use All Goals in Design option is selected.

• On the Parameters tab, make sure all three Output Data options are selected.

Some example plots may look different in ADS 2001 vs. ADS 1.5

Because the data display feature is now receiving additional AEL information, ifthe trace type is set to automatic???, it will decide which type of trace to make, andit may not be what you expect. The most-often-encountered change will be a tracethat used to be linear and is now spectral. If you do not like the selected trace type,you can manually change it to the desired trace type.

DSP/CHBT_TH_prj/THCoSim does not simulate in ADS 2001

The example design THCoSim does not simulate in ADS 2001. This is due to thepresence of a deactivated ground connected to a named node in the TH1subnetwork. This condition causes a netlist error (due to a known defect). Acorrected example can be downloaded from the Agilent EEsof EDA Home Pageunder Applications and Examples, Latest Examples.

Com_Sys/MultiChanNL_Budget_prj needs updated display

If you re-simulate Com_Sys/MultiChanNL_Budget_prj/IQ_Mod_Bud.dsn inADS 2001, the display IQ_BudgetSchematic.dds will either not show any data orgenerate an invalid display error. The reason is that the previous schematicequation data all have HB.xxx or HB_NOISE.xxx but the new data do not. Theworkaround is to remove these headers (HB., HB_NOISE., etc.) from each

Agilent Ptolemy Simulation 11

measurement on each displayed graph or table and save the revised .dds file. Youcan do this either using the onscreen editor or through the Trace Options dialogbox (Edit > Item Options > Trace Options).

CDMA

IS95_Measure_prj generates incorrect EVM value

• In the IS95_Measure_prj example, the SymbolTime parameter of modelErrVecMeas (which is now in Obsolete Sinks) is a number without a time unit.This results in an incorrect EVM value. To avoid this problem, manually addthe msec time unit to this parameter.

IS95A_ChnCodec_prj number of frames tested too small

• In the example IS95A_ChnCodec_prj, the number of frames tested in thedesigns is too small to produce an accurate BER/FER for a high SNR. Use alarger number to obtain good BER curves.

CDMA 2000

CDMA2K_Measurement_prj generates incorrect EVM value

• In the CDMA2K_Measurement_prj example, the SymbolTime parameter ofmodel ErrVecMeas (which is now in Obsolete Sinks) is a number without a timeunit. This results in an incorrect EVM value. To avoid this problem, manuallyadd the msec time unit to this parameter.

CDMA2K_RC_TD_prj examples inconsistent with CDMA 2000 standard

• For some examples for forward link in project CDMA2K_RC_TD_prj, thescrambling mode by long PN code and the data mapping for OTD mode are notconsistent with the CDMA 2000 standard. You can still use these examples asreferences because this inconsistency has little influence on systemperformance. This will be revised in 1.5.2.

W-CDMA

PerchCH_prj data slot settings

• In the PerchCH_prj example, the .dsn file has a setting for 1000 slots of data,but the associated dataset (.dds) file was obtained using a setting of 100 slots.Using larger slot numbers provides more accurate results, but lead tosignificantly longer simulation times.

12 Agilent Ptolemy Simulation

Models

CDMA 2000

CDMA2K_CRC_Coder and CDMA2K_CRC_DeCoder enumerated values incorrect

• In the CDMA2K_CRC_Coder and CDMA2K_CRC_DeCoder models, theenumerated values CRC6 0X5 and CRC6 0X47 for the CRCType parameter areincorrect. You can set the Mode Select parameter option to “User defined” andset the values for the Polynomial parameter to the desired CRC generatorpolynomial (i.e., 0X5 or 0X49). This problem will be corrected in 1.5.2 release.

Simulation aborts if MixerIMT2 component does not reference IMT data file

The IMT_File parameter of the MixerIMT2 component expects a filename, and ifyou neglect to specify one, the simulation aborts.

Optimization/Yield AnalysisYield/YieldOpt analysis with discrete distributed random variables

The Yield/YieldOpt analysis fails under the following conditions:

• There is exactly one random variable with a discrete distribution

or

• There is more than one random variable, but all have discrete distribution

The error message displayed is:

Error detected by HPEESOFSIM during Yield Analysis, . . .

The workaround is to add one dummy variable with uniform distribution (orgauss, or lognormal).

There are also potential problems when the random variables have correlationsand some of the random variables have discrete distribution. Currently noworkaround is available.

Possible crash on Simulate/Update Optimization Values

If there are no optimization variables defined and you choose Simulate > UpdateOptimization Values, ADS will crash. The workaround is to make sure a successfuloptimization has been performed before updating values. If you are unsure, saveall data before proceeding.

Optimization/Yield Analysis 13

Optimization update in subnetworks should use intermediate variable

Back annotation of optimized values in subnetworks does not work correctly if theexpression defining the optimization range is set directly for the parameter beingoptimized. The workaround is to use an intermediate variable rather than a directexpression. For example, rather than assigning "50 Ohm {opt 10 Ohm to 100Ohm}" as the resistance of a given resistor, create a variable X = 50 Ohm {opt 10Ohm to 100 Ohm} and set the resistance of interest equal to X.

Importing and ExportingScaled instance may cause failure on export

If you are exporting a hierarchical design using the DXF (hierarchical) orEGS Archive format, and your design contains a scalable instance that you scaledafter placing it, the export will fail. The workaround is to delete the scaledinstance from the hierarchical design, open the source design (for this instance),scale it there, and place it again.

MomentumMomentum RF simulation causes Momentum to crash

Momentum will crash when the following conditions coexist:

• Momentum simulation in RF mode

• Edge mesh ON (the default condition)

• The mesh contains a rectangular cell with two opposite vertices laying on theboundary of the structure:

There is no workaround.

| | +.......0---- ----- = boundary of the structure : : ..... = mesh cell : : 0 = boundary vertex----0.......+ + = non-boundary vertex | |

14 Importing and Exporting

Visualization problem after simulation in RF mode

The Visualization tool may collapse when you invoke the Momentum Visualizationtool after a Momentum simulation in RF mode if the overlap extraction setting inthe mesh options is selected. This problem is caused by a data field being writtento the wrong location in the mesh file. The workaround is to manually edit themesh file after simulation, prior to visualization. This mesh file is located in./<project_name>_prj/mom_dsn/<design_name>/<project>.msh.

Solving in RF mode then plotting S-parameters using the Visualization tool

If you try to plot S-parameters using the Visualization option, for a project thatwas last solved in RF mode, Visualization may crash. This is true when theS-parameters are in either the CITIfile format or the AFS (Adaptive FrequencySweep) format. The problem is caused by the fact that the visualization option isexpecting certain types of data (GAMMA and Z0) that MomentumRF does notgenerate. The workaround is to display the S-parameters obtained fromMomentumRF using the ADS Data Display.

...CdefIA xxx:c1: x y z,c2: x y z,...cx: x y z;Overlap: ErefRA x { x y ... z };beg_Xinfo :...end_Xinfo ;

...

Move the Overlap data lineto follow the end_Xinfo; line

Momentum 15

Translators

MDS and Series IV to ADS

Some MDS components are not correctly placed in layout

When using the MDS to ADS translator, the location and rotation parameters forsome components do not translate correctly in the layout. You can correct thesemanually by editing the layout drawing after translation. You can also force thetranslator to flatten any parametrically defined footprints/layouts. To translateusing this option, set the configuration variableMIGRATION_MDS_FLATTEN_LAYOUT equal to TRUE in the configuration filemigrate.cfg.

Translator will fail if custom Cadence menu is loaded

If you have added the Cadence user menu function (dlc_cadence_menu) to thevariable USER_MENU_FUNCTION_LIST in your de_sim.cfg configuration file,and attempt to use the MDS to ADS or Series IV to ADS translator, the translatormay fail.

The workaround is to delete the cadence function from this list until you are donetranslating, or comment out the entire variable until you are done translating,then restore it prior to launching ADS.

SPICE

Simulator Error

The gauss() function in the spiceFunctions.net function mapping file is now areserved word in the ADS simulator. Using the spiceFunctions.net functionmapping file to resolve undefined functions during simulation will result in asimulator error.

This function can be disabled by preceding the gauss() entry in thespiceFunctions.net file with the comment (;) character if the function is not needed.If it is needed, the gauss() function should be renamed hspice_gauss() in theSPICE netlist prior to import or in the ADS netlist prior to simulation. It alsoneeds to be renamed in the spiceFunctions.net file or directly in the ADS netlistfile.

16 Translators

Design LibrariesFor the design libraries listed below, the standard ADS recommended computerconfigurations are typically acceptable. However, when more complex systems aresimulated, the computer memory requirements may increase. 500 MB swap spaceon UNIX machines and a 300 MB paging file size on PC machines may be requiredto run large designs.

• cdma2000

• DTV

• EDGE

• 3GPP W-CDMA

• WLAN

EDGE

Non-existent example

The online document under EXAMPLES: EDGE Rx-Mobile-Station refers to ablocking characteristics design MS_RxBlocking_Test.dsn; disregard thisinformation as this example does not exist.

Pins off the grid for some models

For some models in this Design Library, some pins are not located on the samegrid, making it difficult to connect wires to them. Use one of the following methodsas a workaround:

• Reduce the grid interval

• Enable the snap-to-pin option through Options > Preferences

• Shift the model slightly when connecting the wire

Design Libraries 17

Different simulation results depending on platform

The model EDGE_FreqErr_OffsetSupp_Meas may give slightly differentsimulation results on SUN platforms than on PC and HP platforms. (This model isonly used in the EDGE_PA_MS_FreqErr_OffsetSupp design of the PA examplesproject.) EDGE_EVM_WithRef and EDGE_EVM_Meas components are used forEVM measurement.

• EDGE_EVM_WithRef is in compliance with the Agilent 89440 Vector SignalAnalyzer

• EDGE_EVM_Meas is in compliance with Option 202 of Agilent E4406A VectorSignal Analyzer that assumes a full structured burst (the 89440 does not).

Limitations not documented

On the IBM AIX platform, several application examples (MS_RxMRSL.dsn, forexample) and certain customer-designed complex EDGE systems may notsuccessfully simulate if the system limit and/or the hpeesofsim executable fileheader are not set correctly. For details, refer to the topic, “IBM AIX MemoryProblems Simulating Very Large Designs” in Chapter 2, Requirements on UNIXSystems, of the Installation on UNIX Systems manual.

Improving performance of computationally intensive designs

End-to-end BER and BLER simulations involving thousands of bursts andincluding framing, encoding, multipath Rayleigh channel, bit synchronization andequalization are computationally intensive. The platform of choice and simulationparameter settings in the design can be optimized for improved performance inthese cases.

3GPP W-CDMA

Miscalculated BER for WCDMA3G_UE_FixedRateDemod component

The BER (bit error rate) calculation in the WCDMA3G_UE_FixedRateDemodcomponent is slightly off due to the use of the first frame of data output from thereceiver in the BER calculation. This problem will be corrected in a future release.

Waveforms in online help are out of date

Measurement designs WCDMA3G_PA_UE_PkCodeError.dsn andWCDMA3G_PA_UE_OccupiedBW.dsn have been updated but their associatedwaveforms in online help are slightly behind the current version.

18 Design Libraries

Additional information on the WCDMA3G_SignalSources_prj example project

The WCDMA3G_SignalSources_prj Examples project is defined to show how tocreate 3GPP RF signals that model RF signals generated by the Agilent ESGSeries Signal Generators (E443xB) and perform measurements on these signalsincluding Signal Power Spectrum, Peak to Mean Ratio, CCDF (complementarycumulative distribution function) and EVM (error vector magnitude). Essentially,this project provides 3GPP signals that are compliant with those generated by theESG instrument option 100; it is not expected that signals generated in thisproject are compliant with ESG option 200 at this time.

This 3GPP product contains content for the 3GPP FDD mode and does not includeany 3GPP TDD mode capability. A separate product with a separate license isplanned for a future release that will support the 3GPP TDD.

Limitations not documented

On the IBM AIX platform, several application examples (MS_RxMRSL.dsn, forexample) and certain customer-designed complex EDGE systems may notsuccessfully simulate if the system limit and/or the hpeesofsim executable fileheader are not set correctly. For details, refer to the topic, “IBM AIX MemoryProblems Simulating Very Large Designs” in Chapter 2, Requirements on UNIXSystems, of the Installation on UNIX Systems manual.

Improving performance of computationally intensive designs

End-to-end BER and BLER simulations involving thousands of bursts andincluding framing, encoding, multipath Rayleigh channel, bit synchronization andequalization are computationally intensive. The platform of choice and simulationparameter settings in the design can be optimized for improved performance inthese cases.

Electronic NotebookAdding Data Display pages to an existing Electronic Notebook

If you attempt to add a Data Display page (using Add Page and the New NotebookPage dialog box) to an existing notebook, and that page is actually a combination oftwo or more data display files (such as you might create using the SmartSimulation Wizard), the Electronic Notebook may crash.

The workaround is to delete the existing /notebook directory in the project ofinterest and generate the notebook again.

Electronic Notebook 19

Instrument ServerProblem Writing Time Domain Data with Multiple Variables

When you write time domain data in MDIF-TIM format from a dataset containingmore than one variable, only the first variable in the dataset is exported. You can’tselect the parameters that you want to export. This will be fixed in a futurerelease.

Do Not Use Reserved Variables with the Instrument Server

If you attempt to use an ADS reserved variable in the variable definitions in theGMDIF file for the instrument server, the first value in the dataset will beincorrect.

Multi-sweep MDIF Files Improperly Created in Instrument Server

The instrument server will not write correct results to an MDIF file if the datasetincludes more than one sweep.

DC Data Improperly Exports to CITI File

If you simulate a DC curve tracer, export the dataset to a CITI file, then import theCITI file into a dataset, the original data is not the same.

Workaround: The CITI standard only supports the real/imaginary format. If youset the instrument server format selection to real/imaginary, the dataset will beproperly imported and exported.

Errors in Touchstone File Generated from Dataset

The Touchstone data format does not support S-parameter data with unequaltermination impedances; however, when using the instrument server to create aTouchstone file for this type of simulation data, the instrument server will not flagthe error and will incorrectly write the Touchstone file with the terminationimpedance incorrectly listed as R=50.

Problem With Datasets Having .ds Extension

The instrument server does not overwrite existing dataset data blocks, thus aunique blockname is required for every read of an instrument or file. You willreceive an error message reporting the need for a unique blockname; however, onWin2000, ADS may hang if you close the Instrument Server immediately afterreceiving this error message.

20 Instrument Server

Improper Reading of Units in Time Domain Measurements

The instrument server currently does not support time domain measurementsfrom a network analyzer. If you attempt to enter these measurements, thestop/start units will be returned as Hz, when they should be in seconds.

Printing/PlottingColor Images Printed in Black and White

Xprinter cannot print color graphics saved as EPS, PCL4, or PCL5 files. Tryprinting directly to the LaserJet 5M printer or assign the 5M to FILE instead ofprinter.

Hardcopy and Screen Colors Differ

The HP Color LaserJet printer has problems printing color hardcopy from UNIXinstallations using Xprinter if the PCL Cartridge driver is selected. The colors inthe hardcopy produced using this driver do not match those displayed on themonitor.

Use the Color LaserJet PS driver when generating color hardcopy or print inmonochrome.

HPGL/2 Output and TrueType Fonts

If your design contains any TrueType fonts and you print to file using the HPGL/2format, your text will be lost. To preserve it, convert it to HersheyRomanNarrowas follows:

• Component Text—Choose Select > Select All. Choose Edit > Component >Component Text Attributes. Select HersheyRomanNarrow from the Font typedrop-down list and click OK.

• Other Text—Choose Select > Select All. Choose Edit > Edit Text. SelectHersheyRomanNarrow from the Font Type drop-down list and click OK.

Printing/Plotting 21

Design GuidesNode Name Data Missing in RF System DG Envelope Simulations

For some designs in the RF System DesignGuide, the node names fromsubnetworks do not show up in the schematic, resulting in a simulation error. Thisoccurs in designs using circuit envelope simulations with modulated signals.

Workaround: Enter the complete path for the subnetwork in the MeasEqn dialogbox. For example, in the Transmitter/Receiver design, with an Up Convertersubnetwork, you would enter the following:

Vfund_out=mix (Up Converter. V_RF_Out, {1,1})

This problem will be corrected in a future release.

Problems with Auto Simulate in Passive DesignGuide

In the Passive Circuit DesignGuide, in some situations, selecting the AutoSimulate command might cause ADS to crash.

Workaround: Avoid selecting Auto Simulate during the simulation or while thedisplay is opening or updating. These processes might require a few momentsduring which there is little or no activity visible on your screen.

Problems with DSP Designs and Passive DG Designs Open at Once

In the Passive Circuit DesignGuide, the DesignGuide application might notfunction correctly if both a Schematic window including a DSP design and aSchematic window displaying an Analog/RF passive design are open at once.

Workaround: When using the Passive DesignGuide, all open schematic windowsshould contain only Analog/RF designs.

Inaccurate Name for OFDM Receiver Example in RF System DG

In the RF System DesignGuide, the example labelled OFDM Receiver, selectedfrom the Communication Examples menu, is a transmitter, not an OFDMReceiver.

Wrong Noise Figure Results In RF System DG

In the RF System DesignGuide, the data display equations for noise figure areincorrect.

Workaround: On each equation for calculating noise figure at a node, (such asNF_Mix1_In), add "+1" between the two rightmost parentheses.

22 Design Guides

NF_Mix1_In=10*log(abs((pow(V_Mix1_In.noise,2))/((10**(Gain_Mix1_In/10))*(boltzmann*Kelvin*Noise_BW[0]*R_Mix1_In))))

should be:

NF_Mix1_In=10*log(abs((pow(V_Mix1_In.noise,2))/((10**(Gain_Mix1_In/10))*(boltzmann*Kelvin*Noise_BW[0]*R_Mix1_In)))+1)

DG_Fwd_PilotOnlySR3 Has Incorrect Default Dataset in CDMA2000 DG

In the CDMA2000 Design Guide, no data will be displayed if theDG_Fwd_PilotOnlySR3 option is selected before the DG_Fwd_9ChnannelDSSR1option. If DG_Fwd_9ChnannelDSSR1 is selected first, theDG_Fwd_9ChnannelDSSR1 dataset will also be displayed forDG_Fwd_PilotOnlySR3.

Workaround: When selecting the Forward Link Pilot-only source at SR3, changethe default dataset in the Data Display window to DG_Fwd_PilotOnlySR3.

FwdPilotOnlySR1_Src Has Incorrect Default Dataset in CDMA2000 DG

In the CDMA2000 DesignGuide, an incorrect dataset for FwdPilotOnlySR1_Src isdisplayed.

Workaround: When selecting the Forward Link Pilot-only source at SR1,re-simulate to create a new dataset.

DesignGuide Developer Studio• The Palette Editor does not update the display of an edited bitmap until you log

out and restart ADS (UNIX only)

• There is a refresh problem in the Content Browser. If you map content to asubnetwork collector, it only displays the first nine characters in thesubnetwork name. If you collapse the subnetwork collector, and re-open it, thenthe full name is displayed.

• SUN OS—If you are editing the Palette Name in the Palette Editor, and youpress the down arrow on the keyboard, it produces an error.

• Report Summary for Palette (and others) has a sizing problem; it is not able toshow all of the information without cutting off some text.

DesignGuide Developer Studio 23

ValiFireInstalling ValiFire with ADS 2001

When doing a full ADS installation, ValiFire software does not get installed. If youwant to install ValiFire, you must choose to do a Custom Installation afterinstalling ADS. When the list of products appears, select ValiFire and VEELINKDesign Library. For a complete ValiFire installation, you must also install AgilentVEE Professional. The VEE product is available when you purchase the completeValiFire Software Suite, and is installed separately.

New information about the ValiFire System Setup and Hardware Suite

New information about system setup and the hardware suite can be found in theupdated version of the Handset PA ValiFire documentation on the Web(http://www.agilent.com/eesof-eda).

See Chapter 1, System Overview and Setup

Additional information about controlling probers with ValiFire

New information about controlling probers can be found in the updated version ofthe Handset PA ValiFire documentation on the Web(http://www.agilent.com/eesof-eda).

See “Controlling Probers, Handlers, and Temperature Chambers” in Chapter 3,Advanced Topics

24 ValiFire

Documentation

Online Access

Vendor Library Components

Help for Vendor Library components is only available from the Component Librarywindow. To display the documentation for a specific vendor component:

From the Component Library window, select a component and choose Help >Component Help .

Data Display

The following help calls from the Options > Preferences dialog box do not work.Refer to the Data Display manual chapter indicated for each for information onsetting these preferences.

Trace > Labels & Symbols (Chapter 3)

Plot > Main (Chapter 2)

Plot > Linear, Stack (Chapter 2)

Plot > Smith (Chapter 2)

Design Guides

• PC only—If you are using the cascading menu configuration, and you attemptto access context-sensitive help (Help > What’s This?) for any given command,you will seldom get the requested information. Context-sensitive help was notenabled for most commands in this release. The workaround is to refer to theappropriate DesignGuide documentation for general guidelines and procedures.Most designs accessed from these commands are not documented in detail.

• For the Passive Circuit DesignGuide components, the context-sensitive help(Help > What’s This?) for the component palette does not work. The workaroundis to place the component of interest in the drawing area, double-click it toaccess the parameters dialog box, and click the Help button.

Documentation 25

MDS Design Translation

When you click the Help button in the MDS to ADS Import dialog box, the topicthat appears is “Translating Designs into ADS.” Note that the preceding topic“Exporting Designs from MDS,” describes the actual first step of the process, whichis using the migrate.ddl script, not the IFF export feature.

Instrument Server

None of the help links for the Instrument Server work. The workaround is toaccess the Using Instruments manual from any program window by selecting Help> Topics and Index > Manuals > Schematic Designs and Display > UsingInstruments.

RFIC Dynamic Link

The Help button for the Netlist File Include component does not work. Assumingyou have installed the online documentation, you can access this information bybringing up the online documentation from any window (Help > Topics and Index)then using the following series of links: Manuals > Design Flow > RFIC DynamicLink User’s Guide. Select the first topic from chapter 9, “Using the Netlist FileInclude Component.”

Search

• The search engine may not return matches for a query if you have a customizedADS installation. Even if a match appears, clicking it may not display the helptopic, resulting in a navigation error. Whether or not this problem occursdepends on how the custom installation was performed and whichdocumentation files were omitted.

• If you are using MS Internet Explorer to view the ADS Documentation, aproblem occurs when using the Search feature. After entering queries for one ormore terms, if you use the Back button or navigation tabs to open another page,then return to the Search, the applet fails when you enter another query. Theerror message that appears is:

Error occurred. Please relaunch your browser and try again.

The workaround is to close the browser, then reopen it from ADS using Help >Topics and Index.

26 Documentation

• Using a partial word for a query entry could prevent the search engine fromfinding any matches. For example, when you perform a query, use a completeterm such as hpeesofsim because no matches will be found for eesofsim.

Errors and Omissions

Installation

Revised documentation for the Load Sharing Facility

UNIX only—The documentation for the Load Sharing Facility (LSF) found in theinstallation manual on the CD-ROM is incomplete. Please refer to the updatedversion of Installation on UNIX Systems on the Web. Please ignore the CD-ROMversion of this topic and use only the updated version on the Web(http://www.agilent.com/eesof-eda).

See “Using LSF Remote Simulation, ” in Appendix D, Using Remote Simulation

Using multiple versions of ADS

If you need to have multiple versions of ADS installed at the same time, there areseveral things you should know about keeping the installations separate anddistinct. A description of how to do this can be found in the updated versions of theinstallation manuals on the Web (http://www.agilent.com/eesof-eda).

See “Using Multiple ADS Versions” in Chapter 3, Installation Procedures

Analog/RF User-defined Models

Incorrect/incomplete compiler information

Chapter 1, Building User-Compiled Analog Models, contains outdated compilerinformation in the section, “Setup Information.” For current compiler information,refer to the installation manual for your platform.

User’s Guide

New documentation of units/scale factors in ADS

A complete description of how units are handled in ADS (missing from the originalADS documentation) can be found in the updated version of the User’s Guide onthe Web (http://www.agilent.com/eesof-eda).

See “Units/Scale Factors” in Chapter 3, Creating Designs

Documentation 27

Documentation for new power pin feature

A description of the power pin (also known as inherited pin) capability, which ismissing from the CD-ROM documentation, can be found in the updated version ofthe User’s Guide on the Web (http://www.agilent.com/eesof-eda).

See “Adding Power Pins” in Chapter 10, Working with Symbols

Series IV Design Translation

Infinity symbol appears instead of multiplier symbol

Appendix B, Nonlinear Model and Component Changes from Series IV to ADS,contains several typographical errors related to symbols. For the following models,infinity symbols appear in equations where they should be multiplier symbols:

Curtice-Quadratic GaAsFET

Curtice-Cubic GaAsFET

Statz (Raytheon) GaAsFET

TriQuint Scalable Nonlinear GaAsFET

28 Documentation

Incomplete description of units in ADS

A complete description of how units are handled in ADS can be found in theupdated version of the User’s Guide on the Web(http://www.agilent.com/eesof-eda).

See “Units/Scale Factors” in Chapter 3, Creating Designs

Expressions, Measurements, and Simulation Data Processing

UNIX Setup Info Missing from Expressions Documentation

The section, “User-Defined Functions” Chapter 2 of the Expressions,Measurements, and Simulation Data Processing manual only documents the setupfor PC systems. If you are using UNIX, you cannot write to the installationdirectory or to the file expressions_init.ael. The setup for user-defined functions onUNIX is as follows:

1. Copy your AEL file containing the expression(s) to the folder:

$HOME/hpeesof/expressions/ael (user configuration)

or

$HPEESOF_DIR/expressions/ael (site configuration)

Create the folders if they don't exist.

2. Create a new file named user_defined_fun.ael in the same directory, if it doesn'talready exist.

3. Add the following line in the user_defined_fun.ael file:

load("myfile")

where myfile is the name of your AEL file.

4. Restart ADS.

The function(s) defined in your AEL file can now be used in MeasEqn items inschematic and in data display equations.

Documentation 29

Customization

New method for creating custom libraries not documented

The Tools menu now offers access to an easier method of defining custom librariesand loading parts from those libraries. The documentation for the previous methodof doing this has been revised and can be found in the updated version of theCustomization and Configuration manual on the Web.

Design Kit Variables

Beginning with the ADS 2001 release, a separate configuration file, design_kit.cfg,has been created for Design Kits. A number of design kit variables that previouslyhad to be set manually in de_sim.cfg, now exist in design_kit.cfg and are loadedautomatically. It is important that you remove the following variables from yourde_sim.cfg file(s) to prevent a conflict in the future when the variables get renamedto support new design kit software:

DESIGN_KIT_DIRECTORY={$HPEESOF_DIR}/design_kitUSER_AEL={%DESIGN_KIT_DIRECTORY}/design_kit_startupLOCAL_AEL={%DESIGN_KIT_DIRECTORY}/design_kit_project_attach

The following seldom-used design kit variables can remain in de_sim.cfg if needed.The first two are supplied in design_kit.cfg with the default value shown.

DESIGN_KIT_LOCAL_OVERRIDE=FALSE

Set to TRUE to read only local ads.lib files.

DESIGN_KIT_NO_MENU=TRUE

Set to FALSE to turn on the design kit menus in all ADS windows.

USER_MENU_FUNCTION_LIST=app_add_design_kit_menus

Rarely used, but also needed to enable design kit menus in schematic andlayout windows.

The variables noted can be deleted from de_sim.cfg if:

• You want to read the system-wide ads.lib files in addition to local ones(DESIGN_KIT_LOCAL_OVERRIDE)

• You do not want to see the old design kit menus (DESIGN_KIT_NO_MENU,USER_MENU_FUNCTION_LIST)

30 Documentation

Momentum

Visualizing Surface Currents of Existing Projects

The Momentum user guide does not describe how to visualize the surface currentsof existing projects with Momentum Visualization.

The surface currents of projects solved with Momentum under ADS 1.0 or ADS 1.1can be visualized using Momentum Visualization. The surface currents shown arethe superposition of weighted port solutions. The definition of a port solution wasaltered in ADS 1.3/1.5. In ADS 1.1 and earlier, a port solution was defined asfollows:

A voltage source is attached to the port under consideration and all other ports areleft open. Consequently, displaying individual port solutions will show standingwave patterns. For the port solution definition in ADS 1.3/1.5, refer to the chapter,Displaying Surface Currents, in the Momentum manual. Port solutions fromADS 1.1 and earlier can be transferred to the ADS 1.3 definition.

Contact Agilent technical support if you have trouble transferring port solutions.

Visualizing Surface Currents Using Discrete Arrow Plots

The Momentum user manual does not mention that arrow plots enable you tovisualize the surface currents using a vector representation.

On a dense, uniform grid, a vector represents the sampled surface current.Normally, the grid density should be appropriate. If not, the discrete arrow plotprovides another way to look at the surface currents. In a method of momentssolution, your circuit is subdivided into a number of cells.

The surface current on each cell is expanded in a set of basis functions(Momentum uses rooftop basis functions). On a cell, there is a basis functionassociated with each edge. The total current on a cell is the linear superposition ofall basis functions with their appropriate amplitude. In the discrete arrow plot, avector is shown in the middle of all cell edges representing the basis functionamplitude.

Documentation 31

DesignGuide Developer Studio

The following limitations are not documented:

• The Tab Dialog Editor is limited to nine buttons.

• The bitmap viewer in the dialog Insert Palette Item is not as wide as the windowwill permit. It wraps the bitmaps to a second row.

• You cannot use an underscore character (_) in the DesignGuide name forpackaging (packaging is the process of creating a DEBIAN archive file).

• The preview feature of the Bitmap Editor only works on the PC.

• The Palette Editor Insert Palette Item/Change Caption feature is only availableon the PC.

• The Content Editor & System Help Editor do not allow file browsing, so thesource ADS projects must reside at the top level of $HOME, and the startingHTML files must reside at the top level of studio_files/<project_name>/doc.

• The DesignGuide Developer Studio only supports a global build in$HPEESOF_DIR, and not a local build in the $HOME/hpeesof.

• When you package a design guide with the DG Developer Studio, you shouldproduce two packages; one for the PC and one for UNIX, to provide compatiblebitmaps.

• UNIX—The background colors for the window pick up the user settings and donot use the ADS window colors. This sometimes makes the user interfacedifficult to view. The default background colors work best.

• When using the Menu Editor, after you have made a change to the name of amenu, there is a delay in the deselecting of one menu before selecting anothermenu is apparent. Please click once and be patient.

Design Guides

• Many DesignGuide schematics contain subnetworks. If the subnetwork has nomodifiable parameters, there is no online help available for it.

32 Documentation

Circuit Components

DividebyN Component also Used in Harmonic Balance

The description for the DividebyN component (Chapter 6, Phase Lock LoopComponents, of the System Models volume), indicates that it works for transientand circuit envelope simulations. It also works for harmonic balance simulations.

Explanation of Tolerances for Options Component

The description of the relationships between tolerances in the Options component(Chapter 5, Simulation Control Items, of the Introductions and Simulationvolume), is incomplete. Additional details follow.

The simulators work using an iterative method to solve the nonlinear equitations.Given an initial guess x_0, it computes a new guess x_1. From that, it computesx_2. This continues until convergence is reached. When x_j is close to x_j−1, thesolution stops changing. Close is defined as follows:

if (x_j− x_j−1 < reltol*x_j + abstol)

then convergedelse keeps iterating

If the difference between the two iterations is less than the relative tolerancetimes the solution plus an absolute tolerance, the convergence is effective.

Initial Guess Setting in Harmonic Balance Simulation

The description for the Use Initial Guess setting (Chapter 5, Simulation ControlItems, of the Introductions and Simulation Components volume), is not clear. Amore accurate description follows.

In the dialog box for the harmonic balance controller, check the Use Initial Guess(Harmonic Balance) box to enter an initial guess for a simulation. This file istypically generated from a previous simulation by enabling Write Final Solution.If no initial guess filename is supplied, a default name is generated internally,using the design name and appending the suffix .hbs. A suffix is neither requirednor added to any user-supplied filename. For example, if you have saved theharmonic balance solution from a previous simulation, you can later do anonlinear noise simulation and use this saved solution as the initial guess,removing the time required to recompute the nonlinear harmonic balance solution.Or you could quickly get to the initial harmonic balance solution, then sweep aparameter to see the changes. In this latter case, you will probably either want to

Documentation 33

disable the Write Final Solution option or use a different filename for the finalsolution to avoid overwriting the initial guess solution.

34 Documentation