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Voltage standing wave ratio of antenna



vswr(antenna,frequency,z0) calculates and plots the voltage standing wave ratio of an antenna, over specified frequency range, and given reference impedance, z0.


vswrant = vswr(antenna,frequency,z0) returns the VSWR of the antenna.


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

h = loopCircular;

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

    3.5836    6.7163    3.3699

Input Arguments

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Antenna object, specified as a scalar.

Frequency range used to calculate VSWR, specified as a vector in Hz. The minimum value of frequency must be 1 kHz.

Example: 50e6:1e6:100e6

Data Types: double

Reference impedance, specified as a scalar in ohms.

Output Arguments

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Voltage standing wave ratio, returned as a vector in dB.

Version History

Introduced in R2015a

See Also