Rotate Antennas and Arrays

To rotate antenna elements in Antenna Toolbox™, use the Tilt and TiltAxis properties. The Tilt property specifies the angles of rotation of the antenna in degrees. The TiltAxis property specifies the one or more axes of rotation (X, Y, Z) of the antenna.

Rotate Single Antenna Element

Create a patch antenna. By default, this antenna is on the X-Y plane.

patch = patchMicrostrip;
show(patch)

To make the antenna lie on the Y-Z plane, rotate it by 90 degrees about the Y-axis. The rotation follows the standard right-hand rule.

patch.TiltAxis ="Y"; 
patch.Tilt = 90;
show(patch)

The patch lies behind the ground plane and is not visible. To make the patch visible change the TiltAxis property to [0 -1 0]. The Tilt property is still 90, but the axis of rotation is now the Y-axis. The negative number in the TiltAxis vector determines the direction of rotation about the Y-axis as per the right-hand rule.

patch.TiltAxis = [0 -1 0];
show(patch)

Rotate Single Antenna Element About Multiple Axes

Create a dipole antenna. Change the direction of rotation of the antenna with two rotations simultaneously. Rotate the antenna by 90 degrees about the axis specified by [0 1 0] and rotate it by 90 degree about the axis specified by [0 1 1].

d = dipole(Tilt=[90 90], TiltAxis=[0 1 0; 0 1 1])
dipole with properties:

        Length: 2
         Width: 0.1000
    FeedOffset: 0
          Tilt: [90 90]
      TiltAxis: [2x3 double]

show(d)

Rotate Dipole-Backed Reflector

The Tilt and TiltAxis properties are available for dipole and reflector elements. Use these properties if you want to model an antenna parallel or perpendicular to the ground plane.

Create a reflector element. By default, the dipole is parallel to the reflector element.

r = reflector;
show(r)

The dipole is the exciter element of the reflector. View its properties.

r.Exciter;

 dipole with properties:

        Length: 0.1500
         Width: 0.0050
    FeedOffset: 0
          Tilt: 90
      TiltAxis: [0 1 0]

Based on the Tilt and TiltAxis properties the dipole element is rotated by 90 degrees about the y-axis and is parallel to the X-Y plane. To make the dipole perpendicular to the X-Y plane, change the Tilt property of the dipole to 0 degrees.

r.Exciter.Tilt = 0;
show(r)

Rotating the reflector element rotates the entire structure by the specified angle. To rotate the complete antenna, use the Tilt property of the reflector object. For example, rotate the reflector by 90 degrees about the X-axis. According to the right-hand rule, the reflector now lies in the X-Z plane with the dipole.

r = reflector;
r.Tilt = 90;
show(r)

Rotate Antenna Array

Create an array of Archimedean spirals with the whole array rotated at 30 degrees about the X-axis and Y-axis. First create one spiral antenna.

s = spiralArchimedean;
l = linearArray(Element=s, ElementSpacing=0.1,...
NumElements=3, Tilt=30, TiltAxis=[1 1 0]);
show(l)

See Also

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