infiniteArray

Create infinite array of 2-D custom antenna in xy-plane

Description

The infiniteArray object is an infinite antenna array in the xy-plane. Infinite array models a single antenna element called the unit cell. Ground plane of the antenna specifies the boundaries of the unit cell. Antenna without a ground plane requires a reflector. The infinite array has a reflector-backed dipole as the default exciter antenna element. The default dimensions are chosen for an operating frequency of 1GHz.

Creation

Description

infa = infiniteArray creates an infinite antenna array in the xy-plane.

infa = infiniteArray(Name=Value)sets properties using one or more name-value arguments. Name is the property name and Value is the corresponding value. You can specify several name-value arguments in any order as Name1=Value1,...,NameN=ValueN. Properties that you do not specify, retain their default values.

For example, infa = infiniteArray(Element=reflector) creates an infinite array of reflector-backed dipole antenna.

Properties

Element — Type of individual antenna element in unit cell

reflector-backed dipole antenna (default) | antenna object | pcbStack object

Type of individual antenna element in an unit cell, specified as an antenna object or a pcbStack object. Back an antenna without a ground plane by a reflector. The ground plane size specifies the unit cell boundaries. Add vias to the infinite array by setting this property to a pcbStack object.

Note

1. You cannot set this property to a pcbStack object for these specifications:

   • Disconnected array of metal-dielectric structures

   • Antenna with multiple dielectric layers, edge feed, and different dimensions of the ground plane and dielectric substrate

   • Antenna that you create with thePCB Antenna Designer app

2. Following antennas are unsupported as an element:

   • cavity, cavityCircular

   • slot, vivaldiAntipodal

   • Antennas with tilted ground planes.

   • All reflector antennas except reflector with a dipole exciter.

Example: reflector

ScanAzimuth — Scan direction in azimuth plane

0 (default) | scalar

Scan direction in azimuth plane, specified as a scalar in degrees.

Example: 25

Data Types: double

ScanElevation — Scan direction in elevation plane

90 (default) | scalar

Scan direction in elevation plane, specified as a scalar in degrees.

Example: 80

Data Types: double

RemoveGround — Remove ground plane

false or 0 (default) | true or 1

Remove the ground plane of the reflector with air substrate, specified as a numeric or logical 1 (true) or 0 (false). When you specify 1, the object removes the ground plane. When you specify 0, the object does not remove the ground plane.

Example: 1

Data Types: logical

Object Functions

axialRatio	Calculate and plot axial ratio of antenna or array
bandwidth	Calculate and plot absolute bandwidth of antenna or array
beamwidth	Beamwidth of antenna
charge	Charge distribution on antenna or array surface
current	Current distribution on antenna or array surface
design	Design prototype antenna or arrays for resonance around specified frequency or create AI-based antenna from antenna catalog objects
efficiency	Calculate and plot radiation efficiency of antenna or array
EHfields	Electric and magnetic fields of antennas or embedded electric and magnetic fields of antenna element in arrays
impedance	Calculate and plot input impedance of antenna or scan impedance of array
info	Display information about antenna, array, or platform
layout	Display array or PCB stack layout
memoryEstimate	Estimate memory required to solve antenna or array mesh
mesh	Mesh properties of metal, dielectric antenna, or array structure
meshconfig	Change meshing mode of antenna, array, custom antenna, custom array, or custom geometry
msiwrite	Write antenna or array analysis data to MSI planet file
numSummationTerms	Change number of summation terms for calculating periodic Green's function
optimize	Optimize antenna or array using SADEA optimizer
pattern	Plot radiation pattern and phase of antenna or array or embedded pattern of antenna element in array
patternAzimuth	Azimuth plane radiation pattern of antenna or array
patternElevation	Elevation plane radiation pattern of antenna or array
peakRadiation	Calculate and mark maximum radiation points of antenna or array on radiation pattern
rcs	Calculate and plot monostatic and bistatic radar cross section (RCS) of platform, antenna, or array
resonantFrequency	Calculate and plot resonant frequency of antenna
returnLoss	Calculate and plot return loss of antenna or scan return loss of array
show	Display antenna, array structures, shapes, or platform
sparameters	Calculate S-parameters for antenna or array
stlwrite	Write mesh information to STL file
vswr	Calculate and plot voltage standing wave ratio (VSWR) of antenna or array element

Examples

Infinite Array of Reflector-Backed Dipoles

Create an infinite array of reflector-backed dipole as the unit cell. Scan the array at boresight. Visualize the unit cell.

infa = infiniteArray(Element=reflector,ScanAzimuth=0, ...
    ScanElevation=90);
show(infa)

Scan Impedance of Infinite Array

Calculate the scan impedance of an infinite array at 1 GHz. To calculate the impedance, scan the infinite array from boresight to horizon in the elevation plane.

infa = infiniteArray;
theta0deg = linspace(0,90,5);
zscan = nan(1,numel(theta0deg));    
    for j = 1:numel(theta0deg)
      infa.ScanElevation = theta0deg(j);
      zscan(1,j) = impedance(infa,1e9);
    end
 plot(theta0deg, real(zscan), 'b',theta0deg, imag(zscan), 'r', LineWidth=2);
legend("Resistance","Reactance",Location="best")
title("Scan Impedance");
xlabel("Scan Elevation Angle (degrees)");
ylabel("Impedance (ohms)");
grid on

Calculate and Plot Scan Impedance at Bore Sight of Metal Infinite Array

Calculate the scan impedance at bore sight of a metal infinite array without ground plane at a frequency of 1 GHz.

h = infiniteArray(Element=reflector,ScanAzimuth=0, ...
    ScanElevation=90,RemoveGround=1);
zin = impedance(h,1e9)

zin = 
51.4656 +26.1751i

impedance(h,1e9)

Plot Scan Impedance at Boresight of Metal-Dielectric Infinite Array

Plot the scan impedance at the boresight of a metal-dielectric infinite array at a frequency of 1 GHz.

ant = patchMicrostrip(Substrate=dielectric("Teflon"));
h = infiniteArray(Element=ant,ScanAzimuth=0,ScanElevation=90);
impedance(h,1e9)

Add Via to Infinite Array

This example shows how to add vias to an infinite array using a pcbStack object.

Create Infinite Array of pcbStack Objects

Create a pcbStack object with an FR4 dielectric substrate. Define the feed dimension and location. Define the via dimension and location. Create an infinite array of this pcbStack object.

f = 1e9;
lambda = 3e8/f;
p = pcbStack;
d = dielectric("FR4");
p.BoardThickness = d.Thickness;
p.Layers = {p.Layers{1} d p.Layers{2}};
p.FeedLocations = [0.02 0 1 3];
p.FeedDiameter = 1e-3;
p.ViaLocations = [0 0 1 3];
p.ViaDiameter = 1e-3;
ant = infiniteArray(Element=p)

ant = 
  infiniteArray with properties:

          Element: [1x1 pcbStack]
      ScanAzimuth: 0
    ScanElevation: 90
     RemoveGround: 0

View Array and Elevation Pattern

View and mesh the array. Plot the elevation pattern of the array at 1 GHz.

figure;
show(ant)

figure;
mesh(ant,MaxEdgeLength=lambda/20)  

figure;
patternElevation(ant,f)

References

[1] Balanis, C.A. Antenna Theory: Analysis and Design. 3rd Ed. New York: Wiley, 2005.

Version History

Introduced in R2015b