circularArray

Create circular antenna array

Description

The circularArray object is a circular antenna array. Circular array finds application in direction of arrival (DoA) systems. You can use circular arrays to perform 2-D scanning, while lowering element counts. These arrays also have the ability for 360-degree scanning. The individual elements in the circular array are part of the same array environment. This property reduces the impact of edge effects and other coupling variation.

Creation

Syntax

array = circularArray

array = circularArray(Name,Value)

Description

array = circularArray creates a circular antenna array in the X-Y plane.

array = circularArray(Name,Value) class to create a circular antenna array, 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.

Properties

Element — Individual antenna type

dipole (default) | vector of objects

Individual antenna type, specified as a vector of objects. This property supports scalar expansion.

Example: 'Element',[monopole,monopole]

Data Types: char | string

NumElements — Number of elements in array

6 (default) | positive scalar integer

Number of elements in the array,specified as a positive scalar integer. The elements in the array are arranged along the X-axis.

Example: 'NumElements',4

Data Types: double

Radius — Radius of array

1 (default) | positive scalar integer

Radius of array, specified as a positive scalar integer in meters.

Example: 'Radius',0.4

Data Types: double

AngleOffset — Starting angle offset for first element in array

0 (default) | real scalar

Starting angle offset for first element in array, specified as a real scalar in degrees.

Example: 'AngleOffset',8

Data Types: double

AmplitudeTaper — Excitation amplitude for antenna elements in array

1 (default) | real positive vector of size 'Element'

Excitation amplitude for antenna elements in the array, specified as a real positive vector of size 'Element'.

Example: 'AmplitudeTaper',[0 1]

Data Types: double

PhaseShift — Phase shift for each element in array

0 (default) | real vector of size 'Element' in degrees

Phase shift for each element in the array, specified as a real vector of size 'Element' in degrees.

Example: 'PhaseShift',[0 2]

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: TiltAxis='Z'

Data Types: double

Object Functions

show	Display antenna, array structures or shapes
info	Display information about antenna or array
layout	Display array or PCB stack layout
show	Display antenna, array structures or shapes
beamwidth	Beamwidth of antenna
charge	Charge distribution on antenna or array surface
correlation	Correlation coefficient between two antennas in array
current	Current distribution on antenna or array surface
design	Design prototype antenna or arrays for resonance around specified frequency
efficiency	Radiation efficiency of antenna
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, dielectric antenna, or array structure
optimize	Optimize antenna or array using SADEA optimizer
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
rcs	Calculate and plot radar cross section (RCS) of platform, antenna, or array
returnLoss	Return loss of antenna; scan return loss of array
sparameters	Calculate S-parameter for antenna and antenna array objects

Examples

Plot Elevation Pattern of Circular Antenna Array

Create a circular antenna array using 10 antenna elements. View the layout of the antenna elements in the array.

ca = circularArray('NumElements',10)

ca = 
  circularArray with properties:

           Element: [1x1 dipole]
       NumElements: 10
            Radius: 1
       AngleOffset: 0
    AmplitudeTaper: 1
        PhaseShift: 0
              Tilt: 0
          TiltAxis: [1 0 0]

figure;
layout(ca)

Display the array.

figure;
show(ca)

Plot the elevation pattern of the circular array at a frequency of 70 MHz.

figure;
patternElevation(ca,70e6)

Version History

Introduced in R2016b