dielectric
Dielectric material to use as antenna substrate
Description
Dielectric material used as a substrate for antennas.
Creation
Description
d = dielectric(material)
d = dielectric(PropertyName=Value)PropertyName is the
property name and Value is the corresponding value. You can specify
several name-value arguments in any order as
PropertyName1=Value1,...,PropertyNameN=ValueN. Properties that you do
not specify, retain their default values.
For example, d =
dielectric(Name="CustomDielectric",EpsilonR=4.5,LossTangent=0.02,Thickness=1e-3)
creates a custom dielectric material of 1mm. thickness with relative permittivity of 4.5,
and loss tangent of 0.02.
Input Arguments
Properties
Object Functions
getMaterialProperties | Calculate dielectric properties of material |
Examples
Use a Teflon dielectric material as a substrate for a PIFA antenna. View the antenna.
d = dielectric("Teflon")d =
dielectric with properties:
Name: 'Teflon'
EpsilonR: 2.1000
LossTangent: 2.0000e-04
Thickness: 0.0060
FrequencyModel: 'Constant'
For more materials see catalog
p = pifa(Height=0.0060,Substrate=d)
p =
pifa with properties:
Length: 0.0300
Width: 0.0200
Height: 0.0060
Substrate: [1×1 dielectric]
GroundPlaneLength: 0.0360
GroundPlaneWidth: 0.0360
PatchCenterOffset: [0 0]
ShortPinWidth: 0.0200
FeedOffset: [-0.0020 0]
Conductor: [1×1 metal]
Tilt: 0
TiltAxis: [1 0 0]
Load: [1×1 lumpedElement]
show(p)
Create a patch microstrip antenna using a substrate with a relative permittivity of 2.70, a loss tangent of 0.002 and a thickness of 0.0008 m. View the antenna.
t = dielectric(Name="Taconic_TLC",EpsilonR=2.70,LossTangent=0.002,... Thickness=0.0008); p = patchMicrostrip(Height=0.0008,Substrate=t)
p =
patchMicrostrip with properties:
Length: 0.0750
Width: 0.0375
Height: 8.0000e-04
Substrate: [1×1 dielectric]
GroundPlaneLength: 0.1500
GroundPlaneWidth: 0.0750
PatchCenterOffset: [0 0]
FeedOffset: [-0.0187 0]
Conductor: [1×1 metal]
Tilt: 0
TiltAxis: [1 0 0]
Load: [1×1 lumpedElement]
show(p)
Create a microstrip patch antenna.
p = patchMicrostrip;
For property values of air and teflon dielectrics, refer Dielectric Catalog.
openDielectricCatalog
Use Teflon as a dielectric substrate. There is an air gap between the patch groundplane and the dielectric.
sub = dielectric(Name=["Air" "Teflon"],EpsilonR=[1 2.1],... Thickness=[0.002 0.004],LossTangent=[0 2e-04]);
Add the substrate to the patch antenna.
p.Substrate = sub; figure show(p)
Create a microstrip patch antenna.
p = patchMicrostrip;
For dielectric properties, use the Dielectric Catalog.
openDielectricCatalog
Use FR4, Teflon and Foam as the three layers of the substrate.
sub = dielectric(Name=["FR4" "Teflon" "Foam"],EpsilonR=... [4.80 2.10 1.03],Thickness=[0.002 0.004 0.001],... LossTangent=[0.0260 2e-04 1.5e-04]);
Add the three layer substrate to the patch antenna.
p.Substrate = sub; figure show(p)
Plot the radiation pattern of the antenna.
figure pattern(p,1.67e9)
Design a dipole antenna backed by a dielectric substrate and an infinite reflector.
Create a dipole antenna of length, 0.15 m, and width, 0.015 m.
d = dipole(Length=0.15,Width=0.015,Tilt=90,TiltAxis=[0 1 0]);
Create a reflector using the dipole antenna as an exciter and the dielectric, teflon as the substrate.
t = dielectric("Teflon")t =
dielectric with properties:
Name: 'Teflon'
EpsilonR: 2.1000
LossTangent: 2.0000e-04
Thickness: 0.0060
FrequencyModel: 'Constant'
For more materials see catalog
rf = reflector(Exciter=d,Spacing=7.5e-3,Substrate=t);
Set the groundplane length of the reflector to inf. View the structure.
rf.GroundPlaneLength = inf; show(rf)
Calculate the radiation pattern of the antenna at 70 MHz.
pattern(rf,70e6)
Compare the gain values of a dipole antenna in free space and dipole antenna on a substrate.
Design a dipole antenna at a frequency of 1 GHz.
d = design(dipole,1e9); l_by_w = d.Length/d.Width; d.Tilt = 90; d.TiltAxis = [0 1 0];
Plot the radiation pattern of the dipole in free space at 1 GHz.
figure pattern(d,1e9);
Use FR4 as the dielectric substrate.
t = dielectric("FR4")t =
dielectric with properties:
Name: 'FR4'
EpsilonR: 4.8000
LossTangent: 0.0260
Thickness: 0.0060
FrequencyModel: 'Constant'
For more materials see catalog
eps_r = t.EpsilonR;
lambda_0 = physconst("lightspeed")/1e9;
lambda_d = lambda_0/sqrt(eps_r);Adjust the length of the dipole based on the wavelength.
d.Length = lambda_d/2; d.Width = d.Length/l_by_w;
Design a reflector at 1 GHz with the dipole as the exciter and FR4 as the substrate.
rf = reflector(Exciter=d,Spacing=7.5e-3,Substrate=t); rf.GroundPlaneLength = lambda_d; rf.GroundPlaneWidth = lambda_d/4; figure show(rf)
Remove the groundplane for plotting the gain of the dipole on the substrate.
rf.GroundPlaneLength = 0; show(rf)
Plot the radiation pattern of the dipole on the substrate at 1 GHz.
figure pattern(rf,1e9);
Compare the gain values.
Gain of the dipole in free space = 2.11 dBi
Gain of the dipole on substrate = 1.93 dBi
