customArrayGeometry

Create array represented by 2-D custom geometry

Description

The customArrayGeometry object is an array represented by a 2-D custom geometry on the X-Y plane. You can use the customArrayGeometry to import a 2-D custom geometry, define feeds to create an array element, and analyze the custom array.

Creation

Syntax

array = customArrayGeometry

array = customArrayGeometry(Name,Value)

Description

array = customArrayGeometry creates a custom array represented by 2-D geometry on the X-Y plane, based on the specified boundary.

array = customArrayGeometry(Name,Value) creates a 2-D array geometry, with additional properties specified by one or more name-value pair arguments. Name is the property name and Value is the corresponding value. You can specify several name-value pair arguments in any order as Name1, Value1, ..., NameN, ValueN. Properties not specified retain their default values.

Output Arguments

array — Custom array geometry

customArrayGeometry object

Custom array geometry, returned as an customArrayGeometry object.

Properties

Boundary — Boundary information in Cartesian coordinates

cell array

Boundary information in Cartesian coordinates, specified as a cell array in meters.

Data Types: double

Operation — Boolean operation performed on boundary list

'P1' (default) | character vector

Boolean operation performed on the boundary list, specified as a character vector. operation set is; [+, -, *].

Example: 'Operation','P1-P2'

Data Types: double

FeedLocation — Array element feed location in Cartesian coordinates

[0 0 0] (default) | three-element vector

Array element feed location in Cartesian coordinates, specified as a three-element vector. The three elements represent the X, Y, and Z coordinates respectively.

Example: 'FeedLocation', [0 0.2 0]

Data Types: double

FeedWidth — Width of feed for array elements

0.0100 (default) | scalar

Width of feed for array elements, specified as a scalar in meters.

Example: 'FeedWidth',0.05

Data Types: double

AmplitudeTaper — Excitation amplitude for array elements

1 (default) | non-negative scalar | vector of non-negative scalars

Excitation amplitude for array elements, specified as a non-negative scalar or vector of non-negative scalars. Set property value to 0 to model dead elements.

Example: 'AmplitudeTaper',3

Data Types: double

PhaseShift — Phase shift for array elements

0 (default) | real scalar | real vector

Phase shift for array elements, specified as a real scalar in degrees or a real vector in degrees.

Example: 'PhaseShift',[3 3 0 0] specified the phase shift for custom array containing four elements.

Data Types: double

Tilt — Tilt angle of array

0 (default) | scalar | vector

Tilt angle of the array specified as a scalar or vector with each element unit in degrees. For more information, see Rotate Antennas and Arrays.

Example: 'Tilt',90,

Example: 'Tilt',[90 90],'TiltAxis',[0 1 0;0 1 1] tilts the array at 90 degrees about the two axes, defined by vectors.

Data Types: double

TiltAxis — Tilt axis of array

[1 0 0] (default) | three-element vector of Cartesian coordinates | two three-element vectors of Cartesian coordinates | 'X' | 'Y' | 'Z'

Tilt axis of the array, specified as:

• Three-element vectors of Cartesian coordinates in meters. In this case, each vector starts at the origin and lies along the specified points on the X-, Y-, and Z-axes.

• Two points in space, each specified as three-element vectors of Cartesian coordinates. In this case, the array rotates around the line joining the two points in space.

• A string input describing simple rotations around one of the principal axes, 'X', 'Y', or 'Z'.

For more information, see Rotate Antennas and Arrays.

Example: 'TiltAxis',[0 1 0]

Example: 'TiltAxis',[0 0 0;0 1 0]

Example: array.TiltAxis = 'Z'

Data Types: double

Object Functions

show	Display antenna or array structure; display shape as filled patch
info	Display information about antenna or array
axialRatio	Axial ratio of antenna
beamwidth	Beamwidth of antenna
charge	Charge distribution on metal or dielectric antenna or array surface
current	Current distribution on metal or dielectric antenna or array surface
EHfields	Electric and magnetic fields of antennas; Embedded electric and magnetic fields of antenna element in arrays
impedance	Input impedance of antenna; scan impedance of array
mesh	Mesh properties of metal or dielectric antenna or array structure
meshconfig	Change mesh mode of antenna structure
pattern	Radiation pattern and phase of antenna or array; Embedded pattern of antenna element in array
patternAzimuth	Azimuth pattern of antenna or array
patternElevation	Elevation pattern of antenna or array
returnLoss	Return loss of antenna; scan return loss of array
sparameters	Calculate S-parameter for antenna and antenna array objects
show	Display antenna or array structure; display shape as filled patch
vswr	Voltage standing wave ratio of antenna

Examples

Create Custom Slot Antenna Array

Create a custom array using customArrayGeometry. Visualize it and plot the impedance. Also, visualize the current distribution on the array.

Create a ground plane with a length of 0.6 m and a width of 0.5 m.

Lp  = 0.6;
Wp  = 0.5;
[~,p1]   = em.internal.makeplate(Lp,Wp,2,'linear');

Create slots on the ground plane with a length 0.05 m and a width of 0.4 m.

Ls  = 0.05;
Ws  = 0.4;
offset = 0.12;
[~,p2]   = em.internal.makeplate(Ls,Ws,2,'linear');
p3 = em.internal.translateshape(p2, [offset, 0, 0]);
p2 = em.internal.translateshape(p2, [-offset, 0, 0]);

Create a feed in between the slots on the ground plane.

Wf  = 0.01;
[~,p4]   = em.internal.makeplate(Ls,Wf,2,'linear');
p5 = em.internal.translateshape(p4, [offset, 0, 0]);
p4 = em.internal.translateshape(p4, [-offset, 0, 0]);

Create an array using the slotted ground plane.

carray = customArrayGeometry;
carray.Boundary = {p1', p2', p3', p4', p5'};
carray.Operation= 'P1-P2-P3+P4+P5';
carray.NumFeeds = 2;
carray.FeedWidth= [0.01 0.01];
carray.FeedLocation = [-offset,0,0 ; offset,0,0];

Visualize the array.

figure; show(carray);

Calculate the impedance of the array using the frequency range of 350 MHz to 450 MHz.

figure; impedance(carray, 350e6:5e6:450e6);

Visualize the current distribution of the array at 410 MHz.

figure; current(carray, 410e6);

References

[1] Balanis, C. A. Antenna Theory. Analysis and Design. 3rd Ed. Hoboken, NJ: John Wiley & Sons, 2005.