# impedance

Input impedance of antenna or scan impedance of array

## Description

example

impedance(antenna,frequency) calculates the input impedance of an antenna and plots the resistance and reactance over a specified frequency.

example

z = impedance(antenna,frequency) returns the impedance of the antenna over a specified frequency.

impedance(array,frequency,elementnumber) calculates and plots the scan impedance of a specified antenna element in an array.

z = impedance(array,frequency,elementnumber) returns the scan impedance of a specified antenna element in an array.

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

## Examples

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Calculate and plot the impedance of a planar dipole antenna over a frequency range of 50MHz - 100MHz.

h = dipole;
impedance (h,50e6:1e6:100e6);

Calculate scan impedance of default linear array over a frequency range of 50MHz to 100MHz.

h = linearArray;
z = impedance(h,50e6:1e6:100e6)
z = 51×2 complex
102 ×

0.2988 - 1.7742i   0.2988 - 1.7742i
0.3101 - 1.6906i   0.3101 - 1.6906i
0.3217 - 1.6088i   0.3217 - 1.6088i
0.3335 - 1.5287i   0.3335 - 1.5287i
0.3455 - 1.4501i   0.3455 - 1.4501i
0.3577 - 1.3728i   0.3577 - 1.3728i
0.3703 - 1.2967i   0.3703 - 1.2967i
0.3831 - 1.2216i   0.3831 - 1.2216i
0.3962 - 1.1476i   0.3962 - 1.1476i
0.4096 - 1.0743i   0.4096 - 1.0743i
⋮

## Input Arguments

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Antenna for impedance analysis, specified as either an antenna object from the catalog, a pcbStack object, an installedAntenna object, or a custom antenna created using either of these:

Example: horn

Array for impedance analysis, specified as an array object from the catalog or a custom array created using:

Example: conformalArray

Frequency range to calculate the impedance, specified as a scalar or a vector in Hertz.

Example: 50e6:1e6:100e6

Data Types: double

Antenna element number in array, specified as a scalar.

Example: 1

Data Types: double

Flag 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 impedance calculations at multiple frequencies for computationally large antennas and arrays.

Example: UseParallel=true

Data Types: logical

## Output Arguments

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Input impedance of antenna or scan impedance of array, returned as a complex number in ohms. The real part of the complex number indicates the resistance. The imaginary part of the complex number indicates the reactance.

Note

Antenna Toolbox™ caches the impedance values while running for the first time so that the subsequent runs are faster.

## Version History

Introduced in R2015a