Journal of Communications and Information Networks, 2018, 3(1): 15-20 doi: 10.1007/s41650-018-0005-6

Special Focus:Advanced Antenna Technologies for Future Wireless Applications

Recent Advances in Reconfigurable Antennas at University of Technology Sydney

Peiyuan Qin,, Shulin Chen, Y. Jay Guo

Corresponding authors: Peiyuan Qin,Peiyuan.Qin@uts.edu.au

作者简介 About authors

Dr. Qin was awarded an Australia Research Council (ARC) Discovery Early Career Researcher Award (DECRA) in 2017. He was a recipient of the UTS Chancellor’s Postdoctoral Research Fellowship in 2015 and CSIRO OCE Postdoctoral Fellowship in 2012. He won the international Macquarie University Research Excellence Scholarship in 2010 and was awarded the Vice-Chancellor’s Commendation for academic excellence by Macquarie University in 2012. One of his journal papers was selected as 2016 Computer Simulation Technology(CST)University Publication Award and he was selected as Finalist of the Best Paper Award in 2017 ISAP. He is currently sever ing the Associate Editor of IEEE Antennas and Wireless Propagation Letters. E-mail:Peiyuan.Qin@uts.edu.au.

His research interests include reconfigurable antennas,leaky-wave antennas,millimeter wave antennas,and adaptive array processing. He has authored or co-authored over 15 journal and conference papers. He was a finalist of ISAP 2017 best paper competition,and his paper was listed as an Honorary Mention in APS-URSI 2017. .

Prof. Guo has chaired numerous international conferences. He was the International Advisory Committee Chair of IEEE VTC2017,General Chair of ISAP2015,iWAT2014 and WPMC’2014,and TPC Chair of 2010 IEEE WCNC,and 2012 and 2007 IEEE ISCIT. He served as a Guest Editor of special issues on“Antennas for Satellite Communications”and“Antennas and Propagation Aspects of 60-90 GHz Wireless Communications,”both in IEEE Transactions on Antennas and Propagation,Special Issue on“Communications Challenges and Dynamics for Unmanned Autonomous Vehicles,”IEEE Journal on Selected Areas in Communications(JSAC),and Special Issue on“5G for Mission Critical Machine Communications”,IEEE Network Magazine. .

Abstract

This paper presents an overview of the recent advances in reconfigurable antennas for wireless communications at University of Technology Sydney. In particular, it reports our latest progress in this research field, including a multi-linear polarization reconfigurable antenna, a pattern reconfigurable antenna with multiple switchable beams, and a combined pattern and polarization reconfigurable antenna.

PDF (5027KB) Metadata Metrics Related articles Export EndNote| Ris| Bibtex  Favorite

Cite this article

Peiyuan Qin. Recent Advances in Reconfigurable Antennas at University of Technology Sydney. [J], 2018, 3(1): 15-20 doi:10.1007/s41650-018-0005-6

Ⅰ. INTRODUCTION

The last decade has witnessed substantial advances in re-configurable antennas(RAs)as they are emerging as one of the key components to achieve cognitive radio for fifth generation (5G) communication systems. By exploiting the reconfiguration of an antenna’s characteristics, the most suitable communication performance characteristics, such as the operating frequency and radiation patterns, can be realized. RAs can also be used to save energy, enhance security, and avoid interference.

In this paper, we review our recent progress in developing RAs using novel technologies. Examples include a multipolarization reconfigurable antenna, a pattern reconfigurable antenna with multiple switchable beams, and a combined pattern and polarization reconfigurable antenna. They represent novel classes of pattern and polarization reconfigurable systems realized by clever combinations of radiating structures and circuit components.

Ⅱ. MULTIPLE-LINEAR POLARIZATION RECONFIGURABLE ANTENNA

Polarization RAs have the ability to enhance the performance of communication systems. Advantageous features include increasing the capacity of multiple-input multipleoutput(MIMO)systems and mitigating signal fading in multipath propagation environments. Previous work mainly focused on the polarization reconfiguration between two orthogonal linear polarizations(LPs), between left-hand circular polarization (LHCP) and right-hand circular polarization (RHCP), and between linear and circular polarizations[1,2,3,4,5,6] However, it has been found that multiple-linear polarization reconfigurations have unique advantages. For example, higher gains can be achieved by using multiple-linear polarization array elements when the array is mounted on moving vehicles through polarization rotation techniques[7]. A few novel designs have been developed to accomplish such reconfigurations[8,9].

A center-fed patch antenna integrated with shorting posts was developed in Ref. [10]to realize four reconfigurable linear polarization states at every 45° rotation angle. The reported antenna was based on a non-reconfigurable center-fed circular patch antenna with a single shorting post, as shown in Fig.1. As is known, the current on the patch of a conventional monopole-like center-fed circular patch antenna is symmetrical along the φ-direction, and the TM0m modes can be excited. Moreover, by placing a shorting post along the x-axis, the fundamental TM11 mode can be excited with the polarization oriented along the x-axis.

Figure 1

Figure 1   Geometry of the circular patch antenna with one shorting post


Consequently, different LP states oriented along specific angles can be obtained by rotating the position of the shorting post along a circle with the same radius in the xy plane. The geometry of such a multiple-linear polarization reconfigurable antenna is shown in Fig.2. Four diodes are used to control the connection between four shorting posts located at 45°intervals and the center patch. Thus, the connections between the ground and the circular patch can be reconfigured, and four rotatable polarization states can be switched so that they are oriented along the φ =0°, φ =45°, φ =90°, and φ=135°directions.

Figure 2

Figure 2   Geometry of the multiple-linear polarization reconfigurable antenna with shorting posts


The measured input reflection coefficients for all four polarization states overlap in the frequency range 2. 33 to 2. 50 GHz. The simulated and measured input reflection coefficients of the antenna are given in Fig.3. The simulated and measured radiation patterns for the φ=0°polarization state at 2. 45 GHz are shown in Fig.4.

Ⅲ. PATTERN RECONFIGURABLE ANTENNA WITH MULTIPLE SWITCHABLE BEAMS

Pattern RAs have attracted significant attention over the last decade. A wideband antenna with a reconfigurable coplanar waveguide(CPW)-to-slotline transition feed is developed to change the radiation patterns between an almost omnidirectional pattern and two end fire patterns, whose main beams are directed toward exactly opposite directions[11]. In Ref. [12], a beam switching quasi-Yagi dipole antenna has been developed. The length of the balun of the antenna is controlled by using PIN diodes, which allow the currents on the two arms of the dipole to have different phase differences. Different phase differences of the currents can lead to different E-plane main beam directions. In Ref. [13], a cylindrical active frequency-selective surface is developed to provide a 3-D beam-scanning reconfigurable antenna, covering a full range of φ=360°.

For a few practical applications, a large scanning range including endfire and boresight directions are highly desired. Take the unmanned aerial vehicle(UAV)as an example: directional antennas with higher gains are employed instead of omnidirectional antennas in order to increase the range of the communication link. A few pattern reconfigurable antennas have been developed to achieve this beam agility to some extent[14,15]. In Ref. [16], a pattern reconfigurable antenna that has the capability to produce five reconfigurable beams in half an elevation plane is presented. The geometry of the an-tenna is shown in Fig.5(a). It is composed of two horizontally placed substrates, a vertically placed feed substrate, and four supporting posts. The height of the air gap between the two horizontal substrates is ha. The vertical feed substrate is cen-trally located and is inserted from the lower substrate to reach the upper substrate. For the upper substrate, the metal of the top layer is removed and a metal radiating layer is printed on the bottom, as shown in Fig.5(b). On this radiating layer are a radiating dipole and two identical parasitic strips placed at a distance d from the center. Four diodes D1-D4 are soldered across small thin slots cut on the two parasitic lines.

Figure 3

Figure 3   Simulated and measured input reflection coefficients of the multilinear polarization reconfigurable antenna: (a) φ =0° and φ =135°; (b) φ=45°and φ=90°


For the lower substrate, as shown in Fig.5(c), six rectan-gular metal squares are printed on the top. It is referred to as a reflecting layer, while the metal on the bottom of this sub-strate is removed. These six metal pieces are connected by sixteen PIN didoes D5-D20.The antenna is fed by a coplanar stripline transferred from a microstrip line.

The proposed antenna has five working modes corresponding to five different beams in an elevation plane(Z-Y plane). For Mode 1, only PIN diodes D5-D20 are switched on. The antenna radiates a boresight beam. For Mode 2, only D1 and D2 are switched on; as a result, the main beam in the H plane is radiated to the right endfire direction (θ ≈90°). For Mode 3, only D3 and D4 are switched on, and the beam is directed toward the left endfire direction. For Mode 4, D1, D2, and D5-D20 are switched on. Compared to Mode 2, the reflector under the dipole is activated and it has an effect on the main beam direction. In this case, the main beam is not directed toward the right endfire direction but is scanned at a right angle (θ ≈45°). Similarly, for Mode 5, D3, D4, and D5-D20 are switched on and the beam is directed toward a left angle. The input reflection coefficients for the five modes are all below−10 dB at 2. 45 GHz. The simulated and mea-sured radiation patterns are given in Fig.6. The measured main beams of the antenna can be steered to approximate−3°(boresight), 98° (right endfire), −94° (left endfire), 52°, and−57°for Mode 1 to Mode 5. The photograph of the antenna is given in Fig.6(f).

Figure 4

Figure 4   Simulated and measured radiation patterns for the φ=0°polarization at 2. 45 GHz: (a)E-plane; (b)H-plane


Figure 5

Figure 5   Schematics of the pattern RA with switchable beams: (a)overview; (b)radiating layer; (c)reflecting layer


Ⅳ. A COMBINED PATTERN AND POLARIZATION RECONFIGURABLE ANTENNA

The ultimate goal of RA research is to develop RAs that can achieve combined frequency, polarization, and pattern re configuration. Some interesting designs have been proposed that can realize Ras, which can reconfigure a combination of two-parameters[17]and of three-parameters[18]. Another two-parameter version is reported in Ref. [19]; a cavity-backed proximity-coupled reconfigurable antenna realizes both polar-ization switching and beam steering.

The geometry of the proposed antenna is shown in Fig.7. It is composed of an upper substrate, a lower substrate, and a cavity-backed ground plane. A patch layer is etched on the top of the upper substrate and a feed network is printed on top of the lower substrate, as shown in Fig.8(a)and(b), respec-tively. The cavity-backed ground plane that is shown is used for impedance matching.

Three linear polarizations along the φ =0°, φ =45°, and φ =90° directions are reconfigured by controlling the two diodes D9 and D10 on the feed network. They are used to connect or disconnect the diagonal feed line and the two branch feed lines. More specifically, when D9 is ON and D10 is OFF, the φ =0° polarization state, which is aligned along the xaxis, is obtained. Similarly, the φ =90° polarization state along the y-axis is obtained when D9 is OFF and D10 is ON. When both D9 and D10 are ON, a 45°polarization state along the diagonal line is achieved. For each of these three polarization states, beam switching can be realized by employing the reconfigurable parasitic lines that are aligned with the specific polarization direction, as shown in Fig.8(a).

Figure 6

Figure 6   H-plane radiation patterns at 2. 45 GHz(red solid line: simulated co-pol. ; black dash line: measured co-pol. ; blue dash-dot line: measured X-pol. ): (a)Mode 1; (b)Mode 2; (c)Mode 3; (d)Mode 4; (e)Mode 5; (f)The photograph of the antenna


Figure 7

Figure 7   Configuration of the reported cavity-backed reconfigurable microstrip antenna


Taking the y-polarized(φ =90°)state as an example, the active parasitic lines are those of groups A and B that are ver-tically printed with PIN diodes D1 and D3. When both diodes are OFF(all the other diodes are also off), the two parasitic lines have the same length(L1). In this case, the main beam is pointing toward the broadside direction. When D3 is ON and D1 is OFF, the right active parasitic line(with length of L1+L2)is longer than the left one(L1). In this scenario, the main beam steers to the−x-axis direction. When D3 is OFF and D1 is ON, the beam is steered to the+x-axis direction. Simi-larly, three reconfigurable beams can be obtained for the other two polarization states by using the reconfigurable parasitic-element network. Overall, the antenna exhibits nine recon-figurable working modes. The measured and simulated|S11|values at 11. 0 GHz for each mode are presented in Fig.9. For each of them, the main beam can be steered in the H-plane amongst the directions θ≈20°, 0°, −20°, with θ=0°being the broadside direction. The simulated and measured radiation patterns for the φ =0°polarization state are shown in Fig.10. The measured realized gains range from 7. 2 to 8. 1 dBi.

Figure 8

Figure 8   Beam switching realized by employing the reconfigurable parasitic lines: (a)Top view of the patch layer; (b)Top view of the feed layer


Figure 9

Figure 9   Simulated and measured |S11| values at 11. 0 GHz for all nine working modes


Figure 10

Figure 10   Simulated and measured radiation patterns for the φ=0°polarization state: (a)θ≈−20°; (b)θ≈0°; (c)θ≈20°


Ⅴ. CONCLUSION

In this paper, several classes of reconfigurable antennas enabled by new technologies are reviewed. They include a multiple-linear polarization reconfigurable antenna, a pattern reconfigurable antenna with multiple switchable beams, and a combined pattern and polarization reconfigurable antenna. These reconfigurable antennas and future extensions have the potential to provide many characteristics desired to enhance current wireless platforms and to enable future cognitive radio and other 5G and beyond wireless systems.

The authors have declared that no competing interests exist.
作者已声明无竞争性利益关系。

Reference

P. Y. Qin , A. R. Weily , Y. J. Guo , et al.

Polarization reconfigurable Uslot patch antenna

[J]. IEEE Transactions on Antennas&Propagation, 2010, 58(10): 3383-3388.

[Cited within: 1]

Y. Li , Z. Zhang. W. Chen , et al.

Polarization reconfigurable slot antenna with a novel compact CPW-to-slotline transition for WLAN application

[J]. IEEE Antennas & Wireless Propagation Letters, 2010, 9(1): 252-255.

[Cited within: 1]

Y. M. Cai , S. Gao , Y. Yin , et al.

Compact-size low-profile wideband circularly polarized omnidirectional patch antenna with reconfigurable polarizations

[J]. IEEE Transactions on Antennas&Propagation, 2016, 64(5): 2016-2021.

[Cited within: 1]

W. Lin , H. Wong .

Polarization reconfigurable wheel-shaped antenna with conical-beam radiation pattern

[J]. IEEE Transactions on Antennas&Propagation, 2015, 63(2): 491-499.

[Cited within: 1]

N. Nguyen-Trong , L. Hall , C. Fumeaux .

A frequency- and polarization-reconfigurable stub-loaded microstrip patch antenna

[J]. IEEE Transactions on Antennas&Propagation, 2015, 63(11): 5235-5240.

[Cited within: 1]

F. Wu , K. M. Luk .

Single-port reconfigurable magneto-electric dipole antenna with quad-polarization diversity

[J]. IEEE Transactions on Antennas&Propagation, 2017, 65(5): 2289-2296.

[Cited within: 1]

T. Debogovic , S. Skokic , J. Bartolic .

Electronically switchable multipolarization circular patch antenna for conformal arrays

[J]. European Conference on Antennas&Propagation,Nice, 2008: 1-4.

[Cited within: 1]

H. Wong , W. Lin , L. Huitema , et al.

Multi-polarization reconfigurable antenna for wireless biomedical system

[J]. IEEE Transactions on Biomedical Circuits&Systems, 2017, 11(3): 652-660.

[Cited within: 1]

W. Lin , H. Wong .

Multipolarization-reconfigurable circular patch antenna with L-shaped probes

[J]. IEEE Antennas&Wireless Propagation Letters, 2017, 16(99): 1549-1552.

[Cited within: 1]

S. L. Chen , F. Wei , P. Y. Qin , et al.

A multi-linear polarization reconfigurable unidirectional patch antenna

[J]. IEEE Transactions on Antennas&Propagation, 2017, 65(8): 4299-4304.

[Cited within: 1]

Y. Li , Z. Zhang , J. Zheng , et al.

Experimental analysis of a wideband pattern diversity antenna with compact reconfigurable CPW-toslotline transition feed

[J]. IEEE Transactions on Antennas&Propagation, 2011, 59(11): 4222-4228.

[Cited within: 1]

P. Y. Qin , Y. J. Guo , C. Ding .

A beam switching quasi-Yagi dipole antenna

[J]. IEEE Transactions on Antennas & Propagation, 2013, 61(10): 4891-4899.

[Cited within: 1]

C. Gu , S. Gao , B. Sanz-Izquierdo , et al.

3-D coverage beam-scanning antenna using feed array and active frequency-selective surface

[J]. IEEE Transactions on Antennas&Propagation, 2017, 65(11): 5862-5870.

[Cited within: 1]

M. Li , S. Q. Xiao , Z. Wang , et al.

Compact surface-wave assisted beam-steerable antenna based on HIS

[J]. IEEE Transactions on Antennas&Propagation, 2014, 62(7): 3511-3519.

[Cited within: 1]

X. Ding , B. Z. Wang .

A novel wideband antenna with reconfigurable broadside and endfire patterns

[J]. IEEE Antennas&Wireless Propagation Letters, 2013, 12(12): 995-998.

[Cited within: 1]

S. L. Chen , P. Y. Qin , W. Lin , et al.

Pattern reconfigurable antenna with five switchable beams in elevation plane

[J]. IEEE Antennas &Wireless Propagation Letters, 2018, 17(3): 454-457.

[Cited within: 1]

P. Y. Qin , Y. J. Guo , Y. Cai , et al.

A reconfigurable antenna with frequency and polarization agility

[J]. IEEE Antennas&Wireless Propagation Letters, 2011, 10(1): 1373-1376.

[Cited within: 1]

L. Ge , Y. Li , J. Wang , et al.

A low-profile reconfigurable cavity-backed slot antenna with frequency,polarization,and radiation pattern agility

[J]. IEEE Transactions on Antennas&Propagation, 2017, 65(5): 2182-2189.

[Cited within: 1]

S. L. Chen , P. Y. Qin , C. Ding , et al.

Cavity-backed proximity-coupled reconfigurable microstrip antenna with agile polarizations and steerable beams

[J]. IEEE Transactions on Antennas&Propagation, 2017, 65(10): 5553-5558.

[Cited within: 1]

/