# impedance

Input impedance of antenna; scan impedance of array

## Syntax

``impedance(antenna,frequency)``
``z = impedance(antenna,frequency)``
``impedance(array,frequency,elementnumber)``
``z = impedance(array,frequency,elementnumber)``

## Description

example

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

example

````z = impedance(antenna,frequency)` returns the impedance of the antenna object, 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. ```

## 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 × 0.2906 - 1.7345i 0.2906 - 1.7345i 0.3019 - 1.6531i 0.3019 - 1.6531i 0.3135 - 1.5735i 0.3135 - 1.5735i 0.3253 - 1.4955i 0.3253 - 1.4955i 0.3374 - 1.4189i 0.3374 - 1.4189i 0.3497 - 1.3435i 0.3497 - 1.3435i 0.3624 - 1.2693i 0.3624 - 1.2693i 0.3754 - 1.1961i 0.3754 - 1.1961i 0.3887 - 1.1237i 0.3887 - 1.1237i 0.4024 - 1.0521i 0.4024 - 1.0521i ⋮ ```

## Input Arguments

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Antenna object, specified as a scalar.

Array object, specified as a scalar.

Frequency range to calculate impedance, specified as a scalar in hertz or a vector with each element unit in Hz.

Example: 50e6:1e6:100e6

Data Types: `double`

Antenna element number in array, specified as a scalar.

Example: 1

Data Types: `double`

## 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