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rf.Sparameter

Model RF complex baseband S-parameter systems

Since R2024b

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Description

Use the idealized baseband rf.Sparameter System object™ to model RF complex baseband S-parameter systems for command line simulation. You can input your S-parameters as a Touchstone file, an sparameters object, or as a rational object. If you describe the S-parameters using a Touchstone file or an sparameters object, the software uses rational fitting to derive a rational object. You can also model your S-parameters data in either the time or the frequency domain and plot the S-parameters characteristics.

To model a RF complex baseband S-parameter system:

  1. Create the rf.Sparameter object and set its properties.

  2. Call the object with arguments, as if it were a function.

To learn more about how System objects work, see What Are System Objects?

Creation

Syntax

rfspara = rf.Sparameter
rfspara = rf.Sparameter(Name=Value)

Description

rfspara = rf.Sparameter creates an idealized S-parameter element that allows you to model complex baseband S-parameter systems.

example

rfspara = rf.Sparameter(Name=Value) sets properties of the rf.Sparameter object using one or more name-value arguments. For example, rfspara = rf.Sparameter(FileName='default.s2p') creates an idealized S-parameter element using the default.s2p Touchstone file. Properties you do not specify retain their default values.

Properties

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Unless otherwise indicated, properties are nontunable, which means you cannot change their values after calling the object. Objects lock when you call them, and the release function unlocks them.

If a property is tunable, you can change its value at any time.

For more information on changing property values, see System Design in MATLAB Using System Objects.

Data Parameters

Data source to model RF complex baseband S-parameter systems, specified as one of the following:

  • file — Select this option to specify a Touchstone file with the extension .s2p. The System object ignores noise and nonlinearity data in imported files.

  • sparameters — Select this option to specify an sparameters object.

  • rational — Select this option to specify a rational object.

Name of the two-port Touchstone data file, specified as a character vector.

Dependencies

To enable this property, set DataSource to file.

S-parameters object as the data source, specified as a sparameters object.

Dependencies

To enable this property, set DataSource to sparameters.

Rational object as the data source, specified as an rational object.

Dependencies

To enable this property, set DataSource to rational.

Signal Parameters

Carrier frequency of the complex baseband modulated signal, specified as a real number or a positive integer in Hz.

Sample rate of the input complex baseband signal, specified as a nonnegative integer of data type double in samples per second.

Usage

Syntax

out = rfsparam(in)

Description

out = rfsparam(in) returns a time-dependent output signal out based on the time-dependent input signal in.

example

Input Arguments

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Time-dependent input signal, specified as a real scalar, real column, complex scalar, or complex column. A column represents consecutive points in time.

Data Types: double | single

Output Arguments

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Time-dependent output signal, returned as a complex scalar or complex column. The output time-dependent signal is equal in size to the input time-dependent signal.

Data Types: double | single

Object Functions

To use an object function, specify the System object as the first input argument. For example, to release system resources of a System object named obj, use this syntax:

release(obj)

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visualizeVisualize idealized amplifier characteristics, S-parameter data, and filter response
stepRun System object algorithm
releaseRelease resources and allow changes to System object property values and input characteristics
resetReset internal states of System object

Examples

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This example uses:

Open Live Script

Create an rf.Sparameter System object.

rfspara = rf.Sparameter(FileName='default.s2p');

Create a 16 QAM input signal.

in = qammod(randi([0 15],1000,1),16,UnitAveragePower=true);

Apply the input signal to the rf.Sparameter System object.

out = rfspara(in)
out = 1000×1 complex

  -0.7813 + 0.3392i
   1.4492 + 1.2168i
   2.3425 - 1.0038i
   1.4688 + 1.2070i
   1.0171 + 2.3449i
   0.1024 - 1.8777i
  -1.4511 - 1.2371i
  -2.3415 + 1.0101i
   0.3228 + 0.7850i
   0.3468 + 0.7810i
      ⋮

Version History

Introduced in R2024b

See Also

Blocks