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waveguideSlotted

Create slotted waveguide antenna

Description

The default waveguideSlotted object creates a slotted waveguide resonating around 2.4 GHz. There are different types of slotted waveguides, including longitudinal slots, transversal slots, center inclined slots, inclined slots, and inclined slots cut into a narrow wall. Slotted waveguide antennas are used in navigation radar as an array fed by a waveguide.

Creation

Description

ant = waveguideSlotted creates a slotted waveguide on the xy- plane with default property values. The default dimensions are chosen for an operating frequency of around 2.4 GHz.

example

ant = waveguideSlotted(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, ant = waveguideSlotted(Height=1) creates a slotted waveguide with a height of 1 meter.

example

Properties

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Length of the waveguide, specified as a real-valued scalar in meters. Length is calculated as number of slots times the wavelength.

Example: 0.760

Data Types: double

Width of the waveguide, specified as a real-valued scalar in meters.

Example: 0.0840

Data Types: double

Height of the waveguide, specified as a real-valued scalar in meters.

Example: 0.0340

Data Types: double

Number of slots, specified as a scalar integer.

Example: 7

Data Types: double

Shape of waveguide slot, specified as one of the following objects: antenna.Circle, antenna.Polygon, antenna.Rectangle, antenna.Ellipse, and antenna.Triangle.

Example: antenna.Rectangle(Length=0.035)

Data Types: double

Distance from the closed face edge to the top slot center, specified as a real-valued scalar in meters.

Example: 0.0503

Data Types: double

Spacing between the centers of two adjacent slots, specified as a real-valued scalar for uniform spacing or real-valued vector of length NumSlots-1 for non-uniform spacing in meters.

Example: 0.0906

Example: [0.0806 0.0906]

Data Types: double

Slot displacement from the center line of the width of the waveguide to the center of the slot, specified as a real-valued scalar for uniform offset or vector of size of 1-by-n where, n < NumSlots for non-uniform offset in meters.

Example: 0.0560

Example: [0.0560 0.0610]

Data Types: double

Slot angle, specified as a real-valued scalar in degrees or a vector with each element unit in degrees. In slotted waveguide the slots are in pairs. You use a vector when you want one slot in the pair to be tilted at a different angle form the other. It varies from - 180o to 180o.

When you specify SlotAngle as a vector, it must have a size of 1-by-n where, n <= NumSlots.

Example: 20

Example: [20 10]

Data Types: double

Plate to close the open-ended side, specified as 0 for open waveguide and 1 for closed waveguide.

Example: 1

Data Types: double

Height of the feed, specified as a real-valued scalar in meters.

Example: 0.0210

Data Types: double

Width of the feed, specified as a real-valued scalar in meters.

Example: 0.0300

Data Types: double

Signed distances from the origin measured along the length and width of the waveguide, specified as a two-element vector with each element in meters.

Example: [-0.3627 0]

Data Types: double

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: metal("Copper")

Lumped elements added to the antenna feed, specified as a lumped element object. You can add a load anywhere on the surface of the antenna. By default, the load is at the feed. For more information, see lumpedElement.

Example: lumpedElement(Impedance=75)

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

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

axialRatioCalculate and plot axial ratio of antenna or array
bandwidthCalculate and plot absolute bandwidth of antenna or array
beamwidthBeamwidth of antenna
chargeCharge distribution on antenna or array surface
currentCurrent distribution on antenna or array surface
designDesign prototype antenna or arrays for resonance around specified frequency or create AI-based antenna from antenna catalog objects
EHfieldsElectric and magnetic fields of antennas or embedded electric and magnetic fields of antenna element in arrays
efficiencyCalculate and plot radiation efficiency of antenna or array
feedCurrentCalculate current at feed for antenna or array
impedanceCalculate and plot input impedance of antenna or scan impedance of array
infoDisplay information about antenna, array, or platform
memoryEstimateEstimate memory required to solve antenna or array mesh
meshMesh properties of metal, dielectric antenna, or array structure
meshconfigChange meshing mode of antenna, array, custom antenna, custom array, or custom geometry
msiwriteWrite antenna or array analysis data to MSI planet file
optimizeOptimize antenna or array using SADEA optimizer
patternPlot radiation pattern and phase of antenna or array or embedded pattern of antenna element in array
patternAzimuthAzimuth plane radiation pattern of antenna or array
patternElevationElevation plane radiation pattern of antenna or array
peakRadiationCalculate and mark maximum radiation points of antenna or array on radiation pattern
rcsCalculate and plot monostatic and bistatic radar cross section (RCS) of platform, antenna, or array
resonantFrequencyCalculate and plot resonant frequency of antenna
returnLossCalculate and plot return loss of antenna or scan return loss of array
showDisplay antenna, array structures, shapes, or platform
sparametersCalculate S-parameters for antenna or array
stlwriteWrite mesh information to STL file
vswrCalculate and plot voltage standing wave ratio (VSWR) of antenna or array element

Examples

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Create and view a slotted waveguide antenna with default property values.

ant = waveguideSlotted
ant = 
  waveguideSlotted with properties:

             Length: 0.8060
              Width: 0.0857
             Height: 0.0428
           NumSlots: 8
               Slot: [1x1 antenna.Rectangle]
          SlotToTop: 0.0403
        SlotSpacing: 0.0806
         SlotOffset: 0.0123
          SlotAngle: 0
          FeedWidth: 0.0020
         FeedHeight: 0.0310
         FeedOffset: [-0.3627 0]
    ClosedWaveguide: 0
          Conductor: [1x1 metal]
               Tilt: 0
           TiltAxis: [1 0 0]
               Load: [1x1 lumpedElement]

show(ant)

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

Plot the radiation pattern of the antenna at 2.45 GHz.

pattern(ant, 2.45e9)

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.

Create a slotted waveguide antenna with the following dimensions.

 ant = waveguideSlotted(Length=806e-3, Width=94e-3, NumSlots=8,...
      Height=44e-3, Slot=antenna.Rectangle(Length=53e-3,Width=6.5e-3), SlotToTop=40.3e-3,...
      SlotSpacing=80.6e-3, SlotOffset=10e-3, FeedHeight=31e-3,...
      FeedOffset=[-362.7e-3 0], FeedWidth=2e-3);
show(ant)  

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

Plot impedance and S-parameters from 2.2 GHz to 2.8 GHz.

freq = 2.2e9:0.025e9:2.8e9;
figure
impedance(ant,freq);

Figure contains an axes object. The axes object with title Impedance, xlabel Frequency (GHz), ylabel Impedance (ohms) contains 2 objects of type line. These objects represent Resistance, Reactance.

s = sparameters(ant,freq);
figure
rfplot(s);

Figure contains an axes object. The axes object with xlabel Frequency (GHz), ylabel Magnitude (dB) contains an object of type line. This object represents dB(S_{11}).

References

[1] Perovic, Una. " Investigation of Rectangular, Unidirectional, Horizontally Polarized Waveguide Antenna with Longitudinal Slotted Arrays Operating at 2.45 GHz".

Version History

Introduced in R2019b