Super-wideband Antenna Technologies for Next
Generation Mobile Systems
Student: Jianjun Liu
Student ID: 41646975
Supervisor:Karu. P. Esselle
Centre for Microwave and Wireless Applications, Electronics Engineering,
Macquarie University, NSW 2109, Australia
jianjun.liu@mq.edu.au
1
Outline
• Introduction
• Antenna requirement
• Antenna development and Case study
• Proposed extremely wideband antenna for
wireless communication Systems
• Conclusion
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Wireless Communication System
-41.3 dBm/MHz maximum power level for UWB
3
Examples for existing communication standard
•
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•
•
•
•
•
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GPS (1.57–1.58 GHz)
WCDMA (1.92–2.17 GHz)
Bluetooth (2.4-2.48GHz)
WLAN 802.11b/g (5.15-5.825)
WLAN802.11b/g (2.4-2.4835)
Wi-max (3.3-3.6GHz)
Commercial UWB (3.1–10.6 GHz)
Vehicle UWB radar system(22-29GHz)
4
Examples for multi-band wireless system
Cellar system (GSM, Bluetooth, CDMA, USMT)
5
Wireless Local Area Network
6
• UWB through wall image operation (0-960MHz)
• Commercial UWB, localization precision(3.1–10.6 GHz)
• vehicle UWB radar system(22-29GHz)
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Antenna Requirement
• Key component
• Antenna performance
Proposal A: multiple antennas are implemented
Each one covers a specific operation spectrum.
Disadvantage:
• Occupy much space for other device
• Increase the system complexity.
• The installation may restrict the system updating possibility after
manufacture.
Proposal B: Utilize single antenna
• Antenna bandwidth can cover more than one operating
frequency bands of multiple wireless communication systems
• Such antenna should have stable radiation-pattern
characteristics over entire frequency range.
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Antenna Development
Lodge’s biconical antennas (1898)
Carter’s improved match biconical
antennas (1939)
The antennas are bulky and too heavy for portable device
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Equiangular spiral antenna
(1959)
log-periodic dipole antenna
(1960)
The movement of the effective radiating region with frequency
results in waveform distortion of a transmitted pulse
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Metal-plate Monopole Antennas
Ratio impedance bandwidth: 13:1 Frequency range :0.8-10.5GHz
J.A. Evans and M.J. Ammann. “Planar trapezoidal and pentagonal monopoles with impedance bandwidths
in excess of 10:1 [C],” IEEE Antennas Propagat. Symp., vol.3, pp. 1558-1561, July, 1999.
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Frequency range :1.38-11.45GHz Ratio Impedance bandwidth: 8.3:1
Kin-Lu Wong, Chih-Hsien Wu, and Saou-Wen Su, “Ultrawide-Band Square Planar Metal-Plate Monopole Antenna With a
Trident-Shaped Feeding Strip, ” IEEE Trans. Antennas Propagation, vol.53, pp1262-1269, April, 2005.
The perpendicular ground plane leads to antennas with high profiles which is
inconvenience for integrating with monolithic microwave integrated circuits (MMIC).
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Microstrip-feed Printed Monopole Antenna
Impedance bandwidth ratio : 3.52:1
Frequency range :2.78-9.78GHz
J. Liang, Choo C. Chiau, X.D. Chen, et al. “Study of a Printed Circular Disc Monopole Antenna for UWB Systems” [J].IEEE
Trans. Antennas Propag., 2005, 53(11):3550-3554.
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CPW-fed Printed Monopole Antennas
Impedance bandwidth ratio : 4.4:1 Frequency range : 2.73-12GHz
J. Liang, L. Guo, C.C. Chiau, X. Chen and C.G. Parini. Study of CPW-fed circular discmonopole antenna for ultra wideband
applications[J].IEE Proc.-Microw. Antennas Propag.,2005,152(6):520-526.
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Complanation Transform from Discone Antenna
Disc
Discone
Coaxial-feeding line
Elliptical patch
Trapezoid ground
plane
CPW feeding line
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Performance for antenna with Trapezoid Ground Plane
a
Dmin
b
wtop
A
t
z
x
y
H
G
Tapered strip
wbottom
B
Dmax
S.-S. Zhong, X.-L. Liang and W. Wang, “Compact elliptical monopole antenna with impedance bandwidth in excess of
21:1,”IEEE Trans. Antennas Propagation, vol.55, pp. 3080-3085, November, 2007.
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Performance Comparison between different printed antenna
tapered
BWNo.2 10.7

 1.7
BWNo.1 6.3
trapeziform
BWNo.4 11.6

 1.6
BWNo.3 7.2
Elliptical
BWNo.6 21.6

2
BWNo.4 11.6
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Characteristic Mode Analysis for Printed Antenna
(a)
(b)
(c)
K. D. Akkerman, T. F. Kennedy, S. A. Long, and J. T. Williams, "Characteristic modes for planar structure feed
design," in Antennas and Propagation Society International Symposium, 2005 IEEE, 2005, pp. 503-506 vol. 2B.
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Characteristic Mode Analysis for Printed Antenna
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a
Dmin
b
wtop
A
t
z
x
y
H
G
Tapered strip
wbottom
B
Dmax
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Modified Coplanar waveguide-fed elliptical monopole
The feeding terminal affect the high frequency impedance matching
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Modified Coplanar waveguide-fed elliptical monopole
With height and width of patch increased,
the lowest limit decrease and ratio bandwidth increase
Width a（mm）
b=30mm
a=30
a=120
Ratio
bandwidth
VSWR≤2
Impedance
bandwidth
(GHz)
VSWR≤2
25.5:1
0.98 - 25
53:1
0.47-25
Ratio
bandwidth
VSWR≤2
Impedance
bandwidth
(GHz)
VSWR≤2
b=30
53:1
0.47-25
b=90
64:1
0.39-25
Height b（mm）
a=120mm
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Modified Coplanar waveguide-fed elliptical monopole
Gap is a crucial parameter,
The gap variation will affect the impedance bandwidth of whole spectrum
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Modified Coplanar waveguide-fed elliptical monopole
Substrate: Rogers
permitivity:3.48，
thickness:1.5mm。
a
b
H
Dmax
Measured bandwidth: 1.02-24.1 GHz,
ratio bandwidth:23:1
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Modified Coplanar waveguide-fed elliptical monopole
(a)
Maximum gain: 7.2dB
Gain decrease：1 substrate loss
2 radiation shifting
Smith chart
(b)
(c)
(d)
(a) f=1.5GHz (b) f=5GHz
(c) f=10GHz (d) f=20GHz
With the frequency increasing, cross polarization increased. Reverse current lead to
pattern distortion and horizontal current lead to cross polarization enhanced.
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Modified Microstrip-fed printed monopole
Based on modified CPW-fed printed
monopole, two modified microstrip-fed
monopole are proposed
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Modified Microstrip-fed printed monopole
Ratio
bandwidth
VSWR≤2
bandwidth
(GHz)
VSWR≤2
Ordinary antenna
20:1
0.47 – 9.8
Proposed antenna
59:1
0.47-28
Antenna type
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Modified Microstrip-fed printed monopole
Top side
Measured bandwidth: 1.08-27.4 GHz,
ratio bandwidth:25:1
Back side
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Modified Microstrip-fed printed monopole
E Plane
H Plane
E Plane
H Plane
(a) f=1.5GHz (b) f=5GHz (c) f=10GHz
(b) (d) f=15GHz(e) f=20GHz
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Modified Microstrip-fed printed monopole
Maximum gain: 6.5 dB
Gain variation between 4-20 GHz: 2.5 Db
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Modified Microstrip-fed printed monopole
Original proposed antenna
Measured bandwidth: 0.85-25 GHz
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Modified Microstrip-fed printed monopole
ordinary
tapered
proposed
2.3-8.1
0.82-8.15
0.82-25
Ratio bandwidth
3.5
9.2
30.5
Input impedance
（Ω）
18 - 145
22-115
40-79
Bandwidth (GHz)
VSWR≤2
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Modified Microstrip-fed printed monopole
Top side
Measured bandwidth: 0.76-35.2 GHz,
ratio bandwidth:46:1
Back side
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Modified Microstrip-fed printed monopole
E Plane
H Plane
E Plane
H Plane
(a) f=1.5GHz (b) f=5GHz (c) f=10GHz
(b) (d) f=15GHz(e) f=20GHz
Radiation shifting is small
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Modified Microstrip-fed printed monopole
Maximum gain: 8.3dB, gain increases in the whole spectrum
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Conclusion
• Three new configuration of monopole antenna for
wireless applications
• Four Techniques can enhance BW:
1 tapered Microstrip-feeding line
2 trapezoid ground plane
3 optimized radiation patch
4 semicircular feeding branch terminal
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