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phased.IsotropicAntennaElement System object

Package: phased

Isotropic antenna element


The IsotropicAntennaElement object creates an antenna element with an isotropic response pattern. This antenna object does not support polarization.

To compute the response of the antenna element for specified directions:

  1. Define and set up your isotropic antenna element. See Construction.

  2. Call step to compute the antenna response according to the properties of phased.IsotropicAntennaElement. The behavior of step is specific to each object in the toolbox.

    Note:   Starting in R2016b, instead of using the step method to perform the operation defined by the System object™, you can call the object with arguments, as if it were a function. For example, y = step(obj,x) and y = obj(x) perform equivalent operations.


H = phased.IsotropicAntennaElement creates an isotropic antenna system object, H. The object models an antenna element whose response is 1 in all directions.

H = phased.IsotropicAntennaElement(Name,Value) creates an isotropic antenna object, H, with each specified property Name set to the specified Value. You can specify additional name-value pair arguments in any order as (Name1,Value1,...,NameN,ValueN).



Operating frequency range

Specify the antenna element operating frequency range (in Hz) as a 1-by-2 row vector in the form of [LowerBound HigherBound]. The antenna element has zero response outside the specified frequency range.

Default: [0 1e20]


Baffle the back of antenna element

Set this property to true to baffle the back of the antenna element. In this case, the antenna responses to all azimuth angles beyond +/– 90 degrees from the broadside (0 degrees azimuth and elevation) are 0.

When the value of this property is false, the back of the antenna element is not baffled.

Default: false


directivityDirectivity of isotropic antenna element
isPolarizationCapablePolarization capability
patternPlot isotropic antenna element directivity and patterns
patternAzimuthPlot isotropic antenna element directivity or pattern versus azimuth
patternElevationPlot isotropic antenna element directivity or pattern versus elevation
plotResponsePlot response pattern of antenna
stepOutput response of antenna element
Common to All System Objects

Create System object with same property values


Expected number of inputs to a System object


Expected number of outputs of a System object


Check locked states of a System object (logical)


Allow System object property value changes


expand all

Create an isotropic antenna operating over a frequency range from 800 MHz to 1.2 GHz. The operating frequency is 1 GHz. Find the response of the antenna at boresight. Then, plot the polar-pattern elevation response of the antenna.

antenna = phased.IsotropicAntennaElement('FrequencyRange',[800e6 1.2e9]);
fc = 1e9;

Obtain the response at boresight.

resp = antenna(fc,[0;0])
resp =


Plot the response pattern.

pattern(antenna,fc,0,[-90:90],'CoordinateSystem','polar','Type','powerdb', ...

Extended Capabilities

Introduced in R2012a

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