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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
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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
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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)
Examples for existing communication standard
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Examples for multi-band wireless system
Cellar system (GSM, Bluetooth, CDMA, USMT)
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Wireless Local Area Network
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• 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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Lodge’s biconical antennas (1898) Carter’s improved match biconical antennas (1939)
Antenna Development
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
The perpendicular ground plane leads to antennas with high profiles which is
inconvenience for integrating with monolithic microwave integrated circuits (MMIC).
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.
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Microstrip-feed Printed Monopole Antenna
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.
Impedance bandwidth ratio : 3.52:1 Frequency range :2.78-9.78GHz
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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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Disc Elliptical patch
DisconeTrapezoid ground plane
Coaxial-feeding line CPW feeding line
Complanation Transform from Discone Antenna
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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.
Performance for antenna with Trapezoid Ground Plane
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.2
.1
10.71.7
6.3
No
No
BW
BW
.6
.4
21.62
11.6
No
No
BW
BW
.4
.3
11.61.6
7.2
No
No
BW
BW
tapered
trapeziform
Elliptical
Performance Comparison between different printed antenna
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(a) (b) (c)
Characteristic Mode Analysis for Printed Antenna
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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Modified Coplanar waveguide-fed elliptical monopole
The feeding terminal affect the high frequency impedance matching
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With height and width of patch increased, the lowest limit decrease and ratio bandwidth increase
Width a ( mm )b=30mm
Ratio bandwidthVSWR≤2
Impedance bandwidth
(GHz) VSWR≤2
a=30 25.5:1 0.98 - 25
a=120 53:1 0.47-25
Height b ( mm )a=120mm
Ratio bandwidthVSWR≤2
Impedance bandwidth
(GHz) VSWR≤2
b=30 53:1 0.47-25
b=90 64:1 0.39-25
Modified Coplanar waveguide-fed elliptical monopole
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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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Substrate: Rogers
permitivity:3.48 , thickness:1.5m
m 。
Dmax
H
a b
Measured bandwidth: 1.02-24.1 GHz, ratio bandwidth:23:1
Modified Coplanar waveguide-fed elliptical monopole
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(a) (b)
(c) (d)
(a) f=1.5GHz (b) f=5GHz (c) f=10GHz (d) f=20GHz
Maximum gain: 7.2dBGain decrease : 1 substrate loss 2 radiation shifting
Smith chart
Modified Coplanar waveguide-fed elliptical monopole
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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Antenna typeRatio
bandwidth
VSWR≤2
bandwidth (GHz)
VSWR≤2
Ordinary antenna 20:1 0.47 – 9.8
Proposed antenna 59:1 0.47-28
Modified Microstrip-fed printed monopole
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Measured bandwidth: 1.08-27.4 GHz, ratio bandwidth:25:1
Top side
Modified Microstrip-fed printed monopole
Back side
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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
Modified Microstrip-fed printed monopole
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Modified Microstrip-fed printed monopole
Maximum gain: 6.5 dBGain variation between 4-20 GHz: 2.5 Db
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Original proposed antenna Measured bandwidth: 0.85-25 GHz
Modified Microstrip-fed printed monopole
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ordinary tapered proposed
Bandwidth (GHz) VSWR≤2
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
Modified Microstrip-fed printed monopole
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Measured bandwidth: 0.76-35.2 GHz, ratio bandwidth:46:1
Modified Microstrip-fed printed monopole
Top side
Back side
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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
Modified Microstrip-fed printed monopole
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Maximum gain: 8.3dB, gain increases in the whole spectrum
Modified Microstrip-fed printed monopole
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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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