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vswr

Calculate and plot voltage standing wave ratio (VSWR) of antenna or array element

    Description

    vswr(object,frequency,z0) calculates and plots the VSWR of an antenna or an array element, over specified frequency range, and a reference impedance of z0 ohms.

    example

    vswRatio = vswr(object,frequency,z0) calculates and returns the VSWR of an antenna or array element, over specified frequency range, and a reference impedance of z0 ohms.

    example

    vswRatio = vswr(___,UseParallel = true) uses the Parallel Computing Toolbox™ to perform VSWR calculations for each frequency in parallel. To use this feature, you need a license to the Parallel Computing Toolbox.

    Examples

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    Plot vswr (voltage standing wave ratio) of a circular loop antenna.

    h = loopCircular;
    vswr(h,50e6:1e6:100e6,50)

    Figure contains an axes object. The axes object with title VSWR, xlabel Frequency (MHz), ylabel Magnitude (dB) contains an object of type line.

    Calculate vswr (voltage standing wave ratio) of a helix antenna.

    h = helix;
    hvswr = vswr(h,2e9:1e9:4e9,50)
    hvswr = 1×3
    
        3.6047    6.7230    3.3524
    
    

    Input Arguments

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    Antenna or array to calculate the VSWR, specified as one of the following options:

    Example: dipole

    Frequency to calculate the VSWR, specified as a scalar for a single frequency or a vector for a frequency range in Hertz.

    Example: 75e6

    Example: 50e6:1e6:100e6

    Data Types: double

    Reference impedance, specified as a scalar in ohms.

    Option to enable parallel pool, specified as a logical value. The default value is false. Set the flag to true or 1 to enable the parallel pool. Use parallel pool to speedup the VSWR calculations at multiple frequencies for computationally large antennas and arrays.

    Example: UseParallel=true

    Data Types: logical

    Output Arguments

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    Voltage standing wave ratio, returned as a scalar in dB for a single analysis frequency and a vector in dB for analysis over a frequency range.

    Version History

    Introduced in R2015a