dipoleHelix
Create helical dipole antenna
Description
The dipoleHelix
object is a helical dipole antenna. The
antenna is typically center-fed. You can move the feed along the antenna length using
the feed offset property. Helical dipoles are used in satellite communications and
wireless power transfers.
The width of the strip is related to the diameter of an equivalent cylinder by this equation
where:
w is the width of the strip.
d is the diameter of an equivalent cylinder.
r is the radius of an equivalent cylinder.
For a given cylinder radius, use the cylinder2strip
utility function to calculate the equivalent width. The
default helical dipole antenna is center-fed. The circular ground plane is on the
xy- plane. Commonly, helical dipole antennas are used in axial
mode. In this mode, the helical dipole circumference is comparable to the operating
wavelength, and has maximum directivity along its axis. In normal mode, the helical
dipole radius is small compared to the operating wavelength. In this mode, the helical
dipole radiates broadside, that is, in the plane perpendicular to its axis. The basic
equation for the helical dipole antenna is:
where:
r is the radius of the helical dipole.
θ is the winding angle.
S is the spacing between turns.
For a given pitch angle in degrees, use the helixpitch2spacing
utility function to calculate the spacing between the
turns in meters.
Creation
Description
creates a helical
dipole antenna. The default antenna operates around 2 GHz.dh
= dipoleHelix
creates a helical dipole antenna, with additional properties specified by
one or more name–value pair arguments. dh
= dipoleHelix(Name,Value)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
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 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 or dielectric antenna or array structure |
meshconfig | Change mesh mode of antenna 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 |
vswr | Voltage standing wave ratio of antenna |
Examples
References
[1] Balanis, C. A. Antenna Theory. Analysis and Design. 3rd Ed. Hoboken, NJ: John Wiley & Sons, 2005.
[2] Volakis, John. Antenna Engineering Handbook. 4th Ed. New York: McGraw-Hill, 2007.
Version History
See Also
spiralArchimedean
| helix
| monopole
| pifa
| helixpitch2spacing
| cylinder2strip