eggCrate

Create egg crate array of Vivaldi antenna elements

Since R2021a

Description

The eggCrate object creates an array of Vivaldi antenna elements arranged in a rectangular egg-crate structure. Egg crate arrays are used in phased array applications in radar systems.

Creation

Syntax

array = eggCrate

array = eggCrate(Name,Value)

Description

array = eggCrate creates an array of Vivaldi antenna elements arranged in a rectangular egg-crate structure in the X-Y plane at an operating frequency of 825 MHz.

array = eggCrate(Name,Value) sets additional Properties using name-value pairs. For example, arr = eggCrate('Element', vivaldiOffsetCavity) creates an egg-crate array of offset Vivaldi antenna elements.

Properties

Element — Vivaldi antenna

vivaldi (default) | vivaldiOffsetCavity

Vivaldi antenna, specified as a vivaldi or vivaldiOffsetCavity object..

Example: 'Element',vivaldi

Size — Number of rows and columns in array

[2 2] (default) | two-element vector

Number of rows and columns in the egg crate array, specified as a two-element vector.

Note

You can use NumElements to determines number of Vivaldi antenna elements in the egg-crate array.

Example: 'Size',[4 4]

Data Types: double

Gap — Spacing between Vivaldi antenna elements

[0 0] (default) | two-element vector

Spacing between the Vivaldi antenna elements, specified as a two-element vector with each element in meters. The first element in the vector represents the spacing between the Vivaldi elements along x-axis. The second element represents the spacing between the Vivaldi elements along y-axis.

Example: 'Gap',[0.1 0.2]

Data Types: double

FeedVoltage — Voltage applied to feed

1 (default) | positive scalar | real positive vector

Magnitude of the voltage applied to the feed, specified as a as a positive scalar or a vector of positive elements in volts. If you specify a vector, the vector should be of the same size as 'NumElements'.

Example: 'FeedVoltage',2

Data Types: double

FeedPhase — Phase shift for each element in array

0 (default) | real scalar | real vector

Phase shift for each element in the array, specified as a real scalar or a vector of real elements in degrees. If you specify a vector, the vector should be of the same size as 'NumElements'.

Example: 'FeedPhase',-12

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

SolverType — Solver for antenna analysis

'MoM' (default) | 'MoM-PO' | 'FMM'

Solver for antenna analysis, specified as the comma-separated pair consisting of 'SolverType' and 'MoM-PO' or 'MoM' (Method of Moments) or 'FMM' (Fast Multipole Method).

Example: 'SolverType','MOM'

Data Types: char

Object Functions

show	Display antenna, array structures or shapes
solver	Access FMM solver for electromagnetic analysis
info	Display information about antenna or array
beamwidth	Beamwidth of antenna
charge	Charge distribution on antenna or array surface
current	Current distribution on antenna or array surface
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 Radiation Pattern of Default Egg-Crate Array

Create a default egg-crate array.

eca = eggCrate

eca = 
  eggCrate with properties:

        Element: [1x1 vivaldi]
           Size: [2 2]
            Gap: [0 0]
    FeedVoltage: 1
      FeedPhase: 0
           Tilt: 0
       TiltAxis: [1 0 0]
     SolverType: 'MoM'

View the array using the show function.

show(eca)

Plot the radiation pattern of the egg-crate array at a frequency of 825 MHz.

pattern(eca,825e6)

Create Egg-Crate Array and Plot Radiation Pattern

Create a 2-by-2 egg-crate array with a spacing of 20 mm between the Vivaldi elements.

eca = eggCrate('Size',[2 2],'Gap',[20e-3 20e-3])

eca = 
  eggCrate with properties:

        Element: [1x1 vivaldi]
           Size: [2 2]
            Gap: [0.0200 0.0200]
    FeedVoltage: 1
      FeedPhase: 0
           Tilt: 0
       TiltAxis: [1 0 0]
     SolverType: 'MoM'

View the array using the show function.

show(eca)

Plot the radiation pattern of the array at a frequency of 0.9 GHz.

pattern(eca,0.9e9)

Create Egg Crate Array and Plot Impedance of all Elements

Create a 1-by-4 egg-crate array with vivaldiOffsetCavity elements.

eca = eggCrate('Element',vivaldiOffsetCavity,'Size',[1 4])

eca = 
  eggCrate with properties:

        Element: [1x1 vivaldiOffsetCavity]
           Size: [1 4]
            Gap: [0 0]
    FeedVoltage: 1
      FeedPhase: 0
           Tilt: 0
       TiltAxis: [1 0 0]
     SolverType: 'MoM'

View array using the show function.

show(eca)

Plot the S-parameters of the array over a frequency range of 14--17 GHz.

s = sparameters(eca,linspace(14e9,17e9,41));
rfplot(s)

More About

NumElements

Determines number of antenna elements in egg crate array as a positive integer value. The NumElements for default egg crate array is 8.

Example: N = arr.NumElements

References

[1] Chu, Hao-Lung, Ghanshyam Mishra, and Satish K. Sharma. “Dual Polarized Wideband Vivaldi 4x4 Subarray Antenna Aperture for 5G Massive MIMO Panels with Simultaneous Multiple Beams.” In 2018 18th International Symposium on Antenna Technology and Applied Electromagnetics (ANTEM), 1–2. Waterloo, ON: IEEE, 2018. https://doi.org/10.1109/ANTEM.2018.8572871.

[2] R. Hahnel and D. Plettemeier, "Dual-polarized Vivaldi array for X- and Ku-Band," Proceedings of the 2012 IEEE International Symposium on Antennas and Propagation,2012, pp. 1-2.

[3] Yan, J., S. Gogineni, Bruno Camps-Raga and J. Brozena. “A Dual-Polarized 2–18-GHz Vivaldi Array for Airborne Radar Measurements of Snow.” IEEE Transactions on Antennas and Propagation, 2016, vol. 64, pp. 781-785.

Version History

Introduced in R2021a