frequencySweep

Create frequency sweep object

Since R2025a

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    Description

    Create a frequency sweep object to setup the interpolation parameters for frequency sweep with a full-wave solver.

    Creation

    Syntax

    h = frequencySweep

    Description

    h = frequencySweep creates a default interpolating sweep object.

    You can set the properties of this object only after its creation. Properties that you do not specify, retain their default values.

    For example, h = frequencySweep; h.NumFreqs = 150; creates a default frequency sweep object and sets the number of frequency points to 150.

    example

    Properties

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    Type of interpolating frequency sweep, specified as:

    • "interp" uses interpolation with the minimum possible set of points within the specified frequency range.

    • "interpWithGrad" uses a gradient-based interpolation technique to predict the next point within the specified frequency range.

    Example: "interpWithGrad"

    Data Types: string

    Maximum error tolerance in subsequent fitting iterations, specified as a negative scalar. The default error tolerance is -80 dB.

    Example: -90

    Data Types: double

    Number of points to discretize frequency range, specified as a positive integer.

    Example: 150

    Data Types: double

    Maximum number of iterations for fitting, specified as a positive integer.

    Example: 50

    Data Types: double

    Object Functions

    getRationalModelRead rational fitting parameters

    Examples

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    This example uses:

    Open Live Script

    Create a frequency sweep object for using a gradient-based interpolating sweep.

    h = frequencySweep;
h.SweepType = "interpWithGrad";
h.NumFreqs = 200;

    Create a dipole antenna. Calculate its S-parameter in the range 60 MHz to 80 MHz using frequency sweep interpolation.

    d = dipole; 
[s,sweeptype] = sparameters(d,[60e6,80e6],SweepOption=h)
    s = 
  sparameters with properties:

      Impedance: 50
       NumPorts: 1
     Parameters: [1×1×200 double]
    Frequencies: [200×1 double]


    sweeptype = 
  frequencySweep with properties:

    SweepType: "interpWithGrad"
       ErrTol: -80
     NumFreqs: 200
     NumIters: 25

    View rational fit parameters of the interpolated sweep.

    g = getRationalModel(sweeptype)
    g = 
  rational with properties:

      NumPorts: 1
      NumPoles: 5
         Poles: [5×1 double]
      Residues: [1×1×5 double]
    DirectTerm: 0.0937
         ErrDB: -161.8155

    Plot the S-parameter.

    figure
rfplot(s)

    Figure contains an axes object. The axes object with xlabel Frequency (MHz), ylabel Magnitude (dB) contains an object of type line. This object represents dB(S_{11}).

    References

    [1] Yuan, Hao-Bo, Wen-Tao Bao, Chung Hyun Lee, Brian F. Zinser, Salvatore Campione, and Jin-Fa Lee. “A Method of Moments Wide Band Adaptive Rational Interpolation Method for High-Quality Factor Resonant Cavities.” IEEE Transactions on Antennas and Propagation 70, no. 5 (2022): 3595–604. https://doi.org/10.1109/TAP.2022.3142281.

    Version History

    Introduced in R2025a

    See Also

    Objects

    Functions