Frequency Reconfigurable Microstrip Patch Antenna
Research Supported by:
NSF CAREER Grant #
ECCS-0845822
Antenna and Microwave Laboratory (AML)
Project Goals
Student: Rafid N. Damman
Professor: Dr. Satish K. Sharma
Graduate Student Mentor: Jennifer Taylor
•Microstrip patch antenna that can be reconfigured to
operate at two frequencies:1.8GHz and 2.4GHz
•Find the best parameters for the antenna to achieve
the best gain, matching, and acceptable radiation
pattern.
•Utilized PIN Diode RF switches to make the antenna
reconfigurable
•Ansoft/AnSys HFSS software used to model the RF
switches and patch antenna.
2D Radiation Pattern: 1.8GHz
Radiation Pattern 1.8Ghz
Ansoft LLC
Name
Theta
Ang
Mag
m1
0.0000
0.0000
2.0282
m2
HFSSDesign 1.8 Ghz Final (SMA Better Position)
90.0000 90.0000 -33.6144
m1
dB(RealizedGainPhi)
Setup1 : Sw eep1
Freq='1.8GHz' Phi='0deg'
30
-6.00
dB(RealizedGainPhi)
Setup1 : Sw eep1
Freq='1.8GHz' Phi='90deg'
-22.00
-60
60
dB(RealizedGainTheta)
Setup1 : Sw eep1
Freq='1.8GHz' Phi='0deg'
-38.00
dB(RealizedGainTheta)
Setup1 : Sw eep1
Freq='1.8GHz' Phi='90deg'
-54.00
m2
-90
90
-120
Antenna Geometry
ANSOFT
Curve Info
0
-30
3D Radiation Pattern: 1.8GHz
120
-150
150
-180
2D Radiation Pattern: 2.4GHz
Radiation Pattern 2.4Ghz
Ansoft LLC
Name
Theta
Ang
Mag
m1
0.0000
0.0000
3.5342
m2
90.0000 90.0000 -21.7073
HFSSDesign 1.8 2.4 Ideal (OFF) EXPERIMENT
-30
dB(RealizedGainPhi)
Setup1 : Sw eep1
Freq='2.4GHz' Phi='0deg'
30
-6.00
dB(RealizedGainPhi)
Setup1 : Sw eep1
Freq='2.4GHz' Phi='90deg'
-22.00
-60
60
dB(RealizedGainTheta)
Setup1 : Sw eep1
Freq='2.4GHz' Phi='0deg'
-38.00
dB(RealizedGainTheta)
Setup1 : Sw eep1
Freq='2.4GHz' Phi='90deg'
-54.00
m2
-90
ANSOFT
Curve Info
0
m1
3D Radiation Pattern: 2.4GHz
90
Key
Substrate thickness: 0.8mm
Substrate Dielectric Constant: 4.4
PIN Diode:
-120
120
Approach
150
-180
S11
S11 Frequency Reconfigurable Microstrip Patch Antenna
Ansoft LLC
HFSSDesign 1.8 2.4 Ideal (ON)
0.00
ANSOFT
Curve Info
dB(S(2,2))
Setup1 : Sw eep1
-2.50
dB(S(2,2))_1
Imported
-5.00
Name
-7.50
Y1
•Upon knowing the thickness and the dielectric constant
of the substrate material I can calculate the width and
length of my rectangular patch using the equations given
in the Antenna Theory and Design textbook by Balanis.
•I run many simulations to find the exact configurations
for the two different lengths to have a resonant frequency
of 1.8GHz and 2.4GHz and the best matching levels.
•Finally, I will include five PIN Diode switches to be able
to add the specified length to the antenna so that the
single antenna can operate at the two different
frequencies.
-150
-10.00
X
Y
m1
1.7999 -19.7207
m2
1.7434 -9.9263
m3
1.8536 -10.1796
m4
2.4000 -16.2450
m5
2.3622 -9.9737
m6
2.4277 -9.7291
m2
m3
All Switches
OFF
m6
m5
-12.50
All Switches
ON
-15.00
m4
-17.50
m1
-20.00
1.50
1.75
2.00
Freq [GHz]
2.25
2.50
Conclusion
•The reconfigurable microstrip patch antenna
was designed with two different frequencies to
operate from 1.75GHz to 1.85GHz and
2.36GHz to 2.42GHz depending on the ON or
OFF state of the five switches.
•These two bands are used in many wireless
communication applications including cell
phone and Bluetooth technologies.