Documentation

dipoleMeander

Create meander dipole antenna

Description

The `dipoleMeander` class creates a meander dipole antenna with four dipoles. The antenna is center fed and it is symmetric about its origin. The first resonance of meander dipole antenna is at 200 MHz.

The width of the dipole is related to the diameter of an equivalent cylindrical dipole by the equation

`$w=2d=4r$`

, where:

• d is the diameter of equivalent cylindrical dipole.

• r is the radius of equivalent cylindrical dipole.

For a given cylinder radius, use the `cylinder2strip` utility function to calculate the equivalent width. The default strip dipole is center-fed. The feed point coincides with the origin. The origin is located on the X-Y plane.

Creation

Syntax

``dm = dipoleMeander``
``dm = dipoleMeander(Name,Value)``

Description

example

``` `dm = dipoleMeander` creates a meander dipole antenna with four dipoles.```
``` `dm = dipoleMeander(Name,Value)` creates a meander dipole antenna with four dipoles, 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

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Dipole width, specified as a scalar in meters.

Example: `'Width',0.05`

Data Types: `double`

Length of individual dipole arms, specified as a vector in meters. The total number of dipole arms generated is :

`$2\ast N-1$`

where N is the number of specified arm lengths.

Example: ```'ArmLength',[0.6000 0.5000 1 0.4000]```

Data Types: `double`

Notch length along the length of the antenna, specified as a scalar in meters.

For example, in a dipole meander antenna with seven stacked arms there are six notches.

Example: `'NotchLength',1`

Data Types: `double`

Notch width perpendicular to the length of the antenna, specified as a scalar in meters.

Example: `'NotchWidth',1`

Data Types: `double`

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

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

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

Tilt angle of the antenna, 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 antenna at 90 degree about two axes, defined by vectors.

Data Types: `double`

Tilt axis of the antenna, 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 antenna 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'.

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

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

Example: `ant.TiltAxis = 'Z'`

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 `design` Design prototype antenna or arrays for resonance at specified frequency `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` S-parameter object `vswr` Voltage standing wave ratio of antenna

Examples

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Create and view the default meander dipole antenna.

`dm = dipoleMeander`
```dm = dipoleMeander with properties: Width: 0.0040 ArmLength: [0.0880 0.0710 0.0730 0.0650] NotchLength: 0.0238 NotchWidth: 0.0170 Tilt: 0 TiltAxis: [1 0 0] Load: [1x1 lumpedElement] ```
`show(dm)`

Plot the radiation pattern of meander dipole antenna at a 200MHz frequency.

```dm = dipoleMeander; pattern(dm,200e6)```

References

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