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

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

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

Calculate and Plot Impedance of Antenna

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 Array

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

antenna — Antenna or array object

scalar handle

Antenna object, specified as a scalar handle.

array — Array object

scalar handle

Array object, specified as a scalar handle.

frequency — Frequency range used to calculate impedance

scalar | vector

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

elementnumber — Antenna element number in array

scalar

Antenna element number in array, specified as a scalar.

Example: 1

Data Types: double

Output Arguments

z — Input impedance of antenna or scan impedance of array

complex number in ohms

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.