plot

Plot specified circuit object parameters on X-Y plane

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Syntax

lineseries = plot(h,parameter)
lineseries = plot(h,parameter1,...,parametern)
lineseries = plot(h,parameter1,...,parametern,format)
lineseries=plot(h,'parameter1',...,'parametern', format ,xparameter,xformat,'condition1',value1,..., 'conditionm',valuem,'freq',freq,'pin',pin)
lineseries = plot(h,'budget',...)
lineseries = plot(h,'mixerspur',k,pin,fin)

Description

lineseries = plot(h,parameter) plots the specified parameter on an X-Y plane in the default format. h is the handle of a circuit ( rfckt ) object. Use the listparam method to get a list of the valid parameters for a particular circuit object, h.

The plot method returns a column vector of handles to lineseries objects, one handle per line. This output is the same as the output returned by the MATLAB® plot function.

lineseries = plot(h,parameter1,...,parametern) plots the specified parameters parameter1,..., parametern from the object h on an X-Y plane.

lineseries = plot(h,parameter1,...,parametern,format) plots the specified parameters parameter1,..., parametern in the specified format. The format determines if RF Toolbox™ software converts the parameter values to a new set of units, or operates on the components of complex parameter values. For example:

  • Specify format as Real to plot the real part of the selected parameter.

  • Specify format as 'none' to plot the parameter values unchanged.

Use the listformat method to get a list of the valid formats for a particular parameter.

lineseries=plot(h,'parameter1',...,'parametern', format ,xparameter,xformat,'condition1',value1,..., 'conditionm',valuem,'freq',freq,'pin',pin) plots the specified parameters at the specified operating conditions for the object h.

xparameter is the independent variable to use in plotting the specified parameters. Several xparameter values are available for all objects. When you import rfckt.amplifier, rfckt.mixer, or rfdata.data object specifications from a .p2d or .s2d file, you can also specify any operating conditions from the file that have numeric values, such as bias.

The following table shows the most commonly available parameters and the corresponding xparameter values. The default settings listed in the table are used if xparameter is not specified.

Parameter Namexparameter values
Pout, Phase, LS11, LS12, LS21, LS22Pin (default), Freq
S11, S12, S21, S22, Sij,NF, IIP3, OIP3, GroupDelay, VSWRIn, VSWROut, GammaIn, GammaOut, FMIN, GammaOPT, RN, TF1, TF2, Gt, Ga, Gp, Gmag, Gmsg, GammaMS, GammaML, K, Delta, Mu, MuPrimeFreq
AM/AM, AM/PMAM

xformat is the format to use for the specified xparameter. No xformat specification is needed when xparameter is an operating condition.

The following table shows the xformat values that are available for the xparameter values listed in the preceding table, along with the default settings that are used if xformat is not specified.

xparameter valuesxformat values
PindBm (default), mW, W, dBW
Freq

THz, GHz, MHz, KHz, Hz

By default, xformat is chosen to provide the best scaling for the given xparameter values.

AMMagnitude (decibels) (default), Magnitude (linear)

condition1,value1,..., conditionm,valuem are the optional condition/value pairs at which to plot the specified parameters. These pairs are usually operating conditions from a .p2d or .s2d file. For some parameters, you can specify a set of frequency or input power values at which to plot the specified parameter.

For example:

  • When plotting large-signal S-parameters as a function of input power, you can specify frequency points of interest using condition/value pairs.

  • When plotting large-signal S-parameters as a function of frequency, you can specify input power levels of interest using condition/value pairs.

  • When plotting parameters as a function of an operating condition, you can specify both frequency and input power values using condition/value pairs.

freq is the optional frequency value, in hertz, at which to plot the specified parameters.

pin is the optional input power value, in dBm, at which to plot the specified parameters.

If h has multiple operating conditions, such as from a .p2d or .s2d file, the plot method operates as follows:

  • If you do not specify any operating conditions as arguments to the plot method, then the method plots the parameter values based on the currently selected operating condition.

  • If you specify one or more operating conditions, the plot method plots the parameter values based on those operating conditions.

  • When you use an operating condition for the xparameter input argument, the method plots the parameters for all operating condition values.

lineseries = plot(h,'budget',...) plots budget data for the specified parameters parameter1,..., parametern from the rfckt.cascade object h.

The following table summarizes the parameters and formats that are available for a budget plot.

Parameter

Format

S11, S12, S21, S22, Sij

Magnitude (decibels)
Magnitude (linear)
Angle (degrees)
Real
Imaginary

OIP3

dBm
dBW
W
mW

NF

Magnitude (decibels)
Magnitude (linear)

lineseries = plot(h,'mixerspur',k,pin,fin) plots spur power of an rfckt.mixer object or an rfckt.cascade object that contains one or more mixers.

k is the index of the circuit object for which to plot spur power. Its value can be an integer or 'all'. The default is 'all'. This value creates a budget plot of the spur power for h. Use 0 to plot the power at the input of h.

pin is the optional scalar input power value, in dBm, at which to plot the spur power. The default is 0 dBm. When you create a spur plot for an object, the previous input power value is used for subsequent plots until you specify a different value.

fin is the optional scalar input frequency value, in hertz, at which to plot the spur power. If h is an rfckt.mixer object, the default value of fin is the input frequency at which the magnitude of the S21 parameter of the mixer, in decibels, is highest. If h is an rfckt.cascde object, the default value of fin is the input frequency at which the magnitude of the S21 parameter of the first mixer in the cascade is highest. When you create a spur plot for an object, the previous input frequency value is used for subsequent plots until you specify a different value.

For more information on plotting mixer spur power, see the Visualizing Mixer Spurs example.

Note

For all circuit objects except those that contain data from a data file, you must perform a frequency domain analysis with the analyze method before calling plot.

Use the Property Editor (propertyeditor) or the MATLAB set function to change Line Properties. The reference pages for MATLAB functions such as figure, axes, and text also list available properties and provide links to more complete property descriptions.

Note

Use the MATLAB plot function to plot network parameters that are specified as vector data and are not part of a circuit (rfckt) object or data (rfdata) object.

Examples

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Open Live Script

Create and analyze a two-wire network object.

 tx1=rfckt.twowire('Radius',7.5e-4)
tx1 = 
   rfckt.twowire with properties:

            Radius: 7.5000e-04
        Separation: 0.0016
               MuR: 1
          EpsilonR: 2.3000
       LossTangent: 0
         SigmaCond: Inf
        LineLength: 0.0100
          StubMode: 'NotAStub'
       Termination: 'NotApplicable'
             nPort: 2
    AnalyzedResult: []
              Name: 'Two-Wire Transmission Line'


 analyze(tx1,1.9e9)
ans = 
   rfckt.twowire with properties:

            Radius: 7.5000e-04
        Separation: 0.0016
               MuR: 1
          EpsilonR: 2.3000
       LossTangent: 0
         SigmaCond: Inf
        LineLength: 0.0100
          StubMode: 'NotAStub'
       Termination: 'NotApplicable'
             nPort: 2
    AnalyzedResult: [1x1 rfdata.data]
              Name: 'Two-Wire Transmission Line'

Plot S12 on X-Y plane

 linesereis = plot(tx1,'S12')

linesereis = 
  Line (S_{12}) with properties:

              Color: [0 0.4470 0.7410]
          LineStyle: '-'
          LineWidth: 0.5000
             Marker: 'none'
         MarkerSize: 6
    MarkerFaceColor: 'none'
              XData: 1.9000
              YData: -0.3130
              ZData: [1x0 double]

  Show all properties

Alternatives

The rfplot function creates magnitude-frequency plots for RF Toolbox S-parameter objects.

See Also

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Introduced before R2006a

RF Toolbox Documentation
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