Create rectangular spiral antenna on xy-plane
spiralRectangular object creates a single or two-arm
rectangular spiral antenna. The default rectangular spiral has two arms, is center-fed
and is on the xy-plane. The default resonating frequency is 7.65
A spiral rectangular antenna is made up of filaments. The distance between the two violet dashed lines in the diagram represents the first filament or the initial width. The distance between the two orange dashed lines in the diagram represents the second filament or the initial length.
a default rectangular spiral antenna object operating at 7.65 GHz.
ant = spiralRectangular
creates a rectangular spiral antenna, with additional Properties
specified by one or more name-value arguments.
ant = spiralRectangular(Name=Value)
the property name and
Value is the corresponding value.
You can specify several name-value arguments in any order as
NameN=ValueN. Properties not specified retain their
NumArms — Number of arms of spiral
2 (default) |
Number of arms of the spiral, specified as
NumTurns — Number of turns in spiral
1.53 (default) | scalar
Number of turns in the spiral, specified as a scalar in meters. One turn length is taken as the length of a complete 360-degree revolution. To calculate the length of 1.25 turns, the first spiral is created up to one turn. Then the length of the second turn is scaled to the given fraction and added to the first turn length.
InitialWidth — Length of first filament along y-axis
0.0010 (default) | scalar
Length of the first filament along the y-axis from the
origin to the mid-line of the strip width of the second filament, specified
as a scalar in meters.
InitialWidth is the width between
the dashed violet color lines in the antenna image.
InitialLength — Length of second filament along x-axis
0.0015 (default) | scalar
Length of the second filament along the x-axis from the
mid line of the first filament to half of the strip width of the third
filament, specified as a scalar in meters.
is the width between the dashed orange color lines in the antenna
StripWidth — Width of strip
4.0500e-04 (default) | scalar
Width of the strip, specified as a scalar in meters.
Spacing — Spacing between turns
0.0011 (default) | scalar
Spacing between turns of the spiral, specified as a scalar in meters.
WindingDirection — Direction of spiral turns (windings)
"CCW" (default) |
Direction of the spiral turns (windings), specified as
"CW" (clockwise) or
Conductor — Type of metal material
"PEC" (default) |
Load — Lumped elements
lumpedElement] (default) |
Lumped elements added to the antenna feed, specified as a
lumpedElement object. You can add a load anywhere on the surface of
the antenna. By default, the load is at the feed. For more information, see
Tilt — Tilt angle of antenna
0 (default) | scalar | vector
Tilt angle of the antenna in degrees, specified as a scalar or vector. For more information, see Rotate Antennas and Arrays.
TiltAxis=[0 1 0;0 1 1]
tilts the antenna at 90 degrees about the two axes defined by the
TiltAxis — Tilt axis of antenna
[1 0 0] (default) | three-element vector | 2-by-3 matrix |
Tilt axis of the antenna, specified as one of these values:
Three-element vector of Cartesian coordinates in meters. In this case, each coordinate in the vector starts at the origin and lies along the specified points on the x-, y-, and z-axes.
Two points in space, specified as a 2-by-3 matrix corresponding to two three-element vectors of Cartesian coordinates. In this case, the antenna rotates around the line joining the two points.
"z"to describe a rotation about the x-, y-, or z-axis, respectively.
For more information, see Rotate Antennas and Arrays.
[0 1 0]
[0 0 0;0 1 0]
|Display antenna, array structures, shapes, or platform|
|Axial ratio of antenna|
|Beamwidth of antenna|
|Charge distribution on antenna or array surface|
|Current distribution on antenna or array surface|
|Design prototype antenna or arrays for resonance around specified frequency or create AI-based antenna from antenna catalog objects|
|Radiation efficiency of antenna|
|Electric and magnetic fields of antennas or embedded electric and magnetic fields of antenna element in arrays|
|Input impedance of antenna or scan impedance of array|
|Mesh properties of metal, dielectric antenna, or array structure|
|Change meshing mode of antenna, array, custom antenna, custom array, or custom geometry|
|Optimize antenna or array using SADEA optimizer|
|Plot radiation pattern and phase of antenna or array or embedded pattern of antenna element in array|
|Azimuth plane radiation pattern of antenna or array|
|Elevation plane radiation pattern of antenna or array|
|Calculate and plot radar cross section (RCS) of platform, antenna, or array|
|Return loss of antenna or scan return loss of array|
|Calculate S-parameters for antennas and antenna arrays|
|Voltage standing wave ratio (VSWR) of antenna or array element|
|Calculate number of turns for specified arm length in rectangular spiral antenna|
Default Rectangular Spiral Antenna
Create and view a default rectangular spiral antenna.
ant = spiralRectangular
ant = spiralRectangular with properties: NumArms: 2 NumTurns: 1.5300 InitialWidth: 0.0010 InitialLength: 0.0015 StripWidth: 4.0500e-04 Spacing: 0.0011 WindingDirection: 'CCW' Conductor: [1x1 metal] Tilt: 0 TiltAxis: [1 0 0] Load: [1x1 lumpedElement]
Plot the radiation pattern of the antenna at the default frequency.
Radiation Pattern of Reflector Backed Rectangular Spiral
Create a rectangular spiral antenna object with two arms and two turns.
ant_d = spiralRectangular(NumArms=2, NumTurns=2, InitialLength=1e-3,... InitialWidth=1e-3, Spacing=0.5e-3, StripWidth=0.5e-3);
Back the spiral using a reflector antenna object.
r = reflector(Exciter=ant_d, GroundPlaneLength=15e-3, GroundPlaneWidth=... 15e-3, Spacing=2e-3, Substrate=dielectric("FR4")); figure show(r);
Plot the radiation pattern of the antenna at the specified frequency.
Rectangular Spiral Antenna with Specified Arm Length
Create a single arm rectangular spiral antenna with a total arm length of 291 mm.
ant = spiralRectangular(NumArms=1, NumTurns=3, InitialLength=4.5e-3,... InitialWidth=4.5e-3, Spacing=3.3e-3, StripWidth=1.2e-3); nT = rectspirallength2turns(ant,291e-3); ant.NumTurns = nT; figure show(ant)
 Nakano, H., H. Yasui, and J. Yamauchi. “Numerical Analysis of Two-Arm Spiral Antennas Printed on a Finite-Size Dielectric Substrate.” IEEE Transactions on Antennas and Propagation 50, no. 3 (March 2002): 362–70. https://doi.org/10.1109/8.999628.
 Nakano, H., J. Eto, Y. Okabe, and J. Yamauchi. “Tilted- and Axial-Beam Formation by a Single-Arm Rectangular Spiral Antenna with Compact Dielectric Substrate and Conducting Plane.” IEEE Transactions on Antennas and Propagation 50, no. 1 (January 2002): 17–24. https://doi.org/10.1109/8.992557.
Introduced in R2020a