invertedL

Create inverted-L antenna over rectangular ground plane

Description

The default invertedL object is an inverted-L antenna mounted over a rectangular ground plane resonating around 1.67 GHz.

The width of the metal strip is related to the diameter of an equivalent cylinder by the equation

$w = 2 d = 4 r$

where:

d = diameter of equivalent cylinder
a = radius of equivalent cylinder

For a given cylinder radius, use the cylinder2strip utility function to calculate the equivalent width. The default inverted-L antenna is center-fed. The feed point coincides with the origin. The origin is located on the xy- plane.

Creation

Syntax

l = invertedL

l = invertedL(Name,Value)

Description

l = invertedL creates an inverted-L antenna mounted over a rectangular ground plane with default property values. The default dimensions are chosen for an operating frequency of around 1.67 GHz.

l = invertedL(Name,Value) creates an inverted-L antenna, 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.

example

Properties

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`Height` — Height of inverted element along z-axis
0.0140 (default) | scalar

Height of inverted element along z-axis, specified a scalar in meters.

Example: 'Height',3

Data Types: double

`Width` — Strip width
0.0020 (default) | scalar

Strip width, specified as a scalar in meters.

Note

Strip width should be less than 'Height'/4 and greater than 'Height'/1001. [2]

Example: 'Width',0.05

Data Types: double

`Length` — Stub length along x-axis
0.0310 (default) | scalar

Stub length along x-axis, specified as a scalar in meters.

Example: 'Length',0.01

`GroundPlaneLength` — Ground plane length along x-axis
0.1000 (default) | scalar

Ground plane length along x-axis, specified a scalar in meters. Setting 'GroundPlaneLength' to Inf, uses the infinite ground plane technique for antenna analysis.

Example: 'GroundPlaneLength',4

Data Types: double

`GroundPlaneWidth` — Ground plane width along y-axis
0.1000 (default) | scalar

Ground plane width along y-axis, specified as a scalar in meters. Setting 'GroundPlaneWidth' to Inf, uses the infinite ground plane technique for antenna analysis.

Example: 'GroundPlaneWidth',2.5

Data Types: double

`FeedOffset` — Signed distance from center along length and width of ground plane
`[0 0]` (default) | two-element vector

Signed distance from center along length and width of ground plane, specified as a two-element vector.

Example: 'FeedOffset',[2 1]

Data Types: double

`Conductor` — Type of metal material
`'PEC'` (default) | `metal` object

Type of the metal used as a conductor, specified as a metal material object. You can choose any metal from the MetalCatalog or specify a metal of your choice. For more information, see metal. For more information on metal conductor meshing, see Meshing.

Example: m = metal('Copper'); 'Conductor',m

Example: m = metal('Copper'); ant.Conductor = m

`Load` — Lumped elements
[1x1 LumpedElement] (default) | lumped element object

Lumped elements added to the antenna feed, specified as a lumped element object. For more information, see lumpedElement.

Example: 'Load',lumpedelement. lumpedelement is the object for the load created using lumpedElement.

Example: l.Load = lumpedElement('Impedance',75)

`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.

Example: 90

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

Data Types: double

`TiltAxis` — Tilt axis of antenna
`[1 0 0]` (default) | three-element vector | 2-by-3 matrix | `"X"` | `"Y"` | `"Z"`

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.
"x", "y", or "z" to describe a rotation about the x-, y-, or z-axis, respectively.

For more information, see Rotate Antennas and Arrays.

Example: [0 1 0]

Example: [0 0 0;0 1 0]

Example: "Z"

Data Types: double | string

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
`feedCurrent`	Calculate current at feed for antenna or array
`impedance`	Calculate and plot input impedance of antenna or scan impedance of array
`info`	Display information about antenna, array, or platform
`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
`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

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Create and View Inverted-L Antenna

Open Live Script

Create and view an inverted-L antenna that has 30mm length over a 200mm-by-200mm ground plane.

il = invertedL(Length=30e-3,GroundPlaneLength=200e-3,...
    GroundPlaneWidth=200e-3);
show(il)

Figure contains an axes object. The axes object with title invertedL antenna element, xlabel x (mm), ylabel y (mm) contains 5 objects of type patch, surface. These objects represent PEC, feed.

Radiation Pattern of Inverted-L Antenna

Open Live Script

Plot the radiation pattern of an inverted-L at a frequency of 1.7 GHz.

iL = invertedL(Length=30e-3,GroundPlaneLength=200e-3,...
    GroundPlaneWidth=200e-3);
pattern(iL,1.7e9)

Figure contains 2 axes objects and other objects of type uicontrol. Axes object 1 contains 5 objects of type patch, surface. Hidden axes object 2 contains 17 objects of type surface, line, text, patch.

References

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

[2] Volakis, John. Antenna Engineering Handbook, 4th Ed. New York: Mcgraw-Hill, 2007.

Version History

Introduced in R2015a

invertedL

Description