Projects

Metamaterial Antennas
Abstract: In this project we study metamaterials to improve conventional antennas in terms of their size, directionality, efficiency, and bandwidth.
Keywords: Metamaterials, Antennas
Collaborators: Fernando L. Teixeira (Ohio State University), Hayrettin Odabasi (Duke University)

Metamaterials have been widely used in many antenna applications as a means to improve overall performance [1–28]. In particular, new electrically small antennas (ESAs) have been designed thanks to miniaturization capabilities enabled by metamaterials [12–16, 21–24]. As summarized in Ref. [23], one effective approach to design ESAs is to employ metaresonators, i.e., split-ring resonators (SRRs) or complementary split-ring resonators (CSRRs), excited by monopole or patch antennas [13–16, 21]. Such combined structure (“metaresonator antenna”) operates near the resonant frequency of the metaresonator, thus allowing for the miniaturization [23]. The mechanism of the electric coupling depends greatly on the antenna and the resonator distance and their frequencies.

Resonant antennas composed of single negative materials were proposed by Isaacs [29]. Being perhaps the most popular element providing negative permeability response, the SRR [30] was employed to design ESA by Alici et al. [13, 14]. They showed that ESAs can be designed by properly exciting the SRR via a monopole antenna. CSRRs that exhibit negative permittivity were studied by Falcone et al. [31,32]. CSRRs were also used for low-profile planar antenna designs [16,21]. Moreover, by employing various resonators in tandem, added functionalities such as dual polarization, circular polarization, or multi-band characteristics can be obtained [15,21]. SRRs are also employed in the design of multi-band and multifunctional printed monopole antennas [17–20], particularly for wireless applications. SRR and CSRR can be considered as parasitic elements inducing coupled (equivalent) magnetic or electric dipole responses, respectively [23]. To enhance the bandwidth of resonant antennas, active devices can also be used [25–28].

As part of this project, we have investigated [33] the use of electric-field-coupled (ELC) [34] and complementary electric-field-coupled (CELC) [35] resonators to design ESAs. It turns out that ELC and CELC resonators can also induce coupled electric and magnetic dipole responses [35]. The advantage here is that otherwise using either SRR or CSRR elements allows for coupling only to the perpendicular (with respect to the resonator plane) magnetic or electric field, respectively, from the active component [14, 21]. This limits the choice of configurations to which SRR and CSRR resonators are useful for one particular orientation only. In contrast, ELC and CELC resonators can couple to both parallel and perpendicular components of the electric or magnetic field, respectively [34, 35]. In the following, we exploit this property to design new ESA configurations as depicted in Fig. 1. Configurations depicted in Fig. 1(d) in particular are both very low-profile. The design of a new low-profile bent-monopole CELC-coupled antenna is also presented.

Figure 1 Schematic configurations of (a) SRR, (b) ELC, (c) CELC-1, and (d) CELC-2, CELC-3 resonator antennas. For the CELC-1,-2,-3 configurations, the respective orientation is indicated in (e).

The height of the monopole antenna and the resonators were designed to be matched approximately, the distance between the resonator and the monopole antenna and ground plane was 0.1mm and 0.6mm respectively, the resonators were FR-4 with 1.6 mm thickness. Considering the coupling, radiation pattern, gain and efficiency, we have found [33] that CELC resonators are more suited than ELC counterparts for ESA configurations because of superior performance and flexibility of the former for excitation in different orientations. In particular, monopole-excited and bent-monopole-excited CELC resonator antennas are proposed that provide very low profiles on the order of 1/20 of the free-space wavelength.

Acknowledgments

We collaborate with Fernando L. Teixiera (Ohio State University) and Hayrettin Odabasi (Duke University).

References

[1] N. Engheta and R. W. Ziolkowski, Metamaterials: Physics and Engineering Explorations (IEEE, Wiley, 2006).
[2] C. Caloz and T. Itoh, Electromagnetic Metamaterials: Transmission Line Theory and Microwave Applications (IEEE, Wiley, 2005).
[3] F. Yang and Y. Rahmat-Sami, Electromagnetic Band-Gap Structures in Antenna Engineering (Cambridge University Press, Cambridge, UK, (2009).
[4] D. Sievenpiper, L. Zhang, R. Broas, N. Alexopolous, and E. Yablonovitch, IEEE Trans. Microwave Theory Tech. 47, 2059 (1999).
[5] F. Yang and Y. Rahmat-Samii, IEEE Trans. Antennas Propag. 51, 2691 (2003).
[6] D. Kern, D. Werner, A. Monorchio, L. Lanuzza, and M. Wilhelm, IEEE Trans. Antennas Propag. 53, 8 (2005).
[7] H. Mosallaei and K. Sarabandi, IEEE Trans. Antennas Propag. 52, 2403 (2004).
[8] H. Mosallaei and K. Sarabandi, IEEE Trans. Antennas Propag. 52, 1558 (2004).
[9] P. Ikonen, K. Rozanov, A. Osipov, P. Alitalo, and S. Tretyakov, IEEE Trans. Antennas Propag. 54, 3391 (2006).
[10] K. Buell, H. Mosallaei, and K. Sarabandi, IEEE Trans. Microwave Theory Tech. 54, 135 (2006).
[11] F. Qureshi, M. Antoniades, and G. Eleftheriades, IEEE Antennas Wireless Propag. Lett. 4, 333 (2005).
[12] P. Jin and R. Ziolkowski, IEEE Trans. Antennas Propag. 59, 1446 (2011).
[13] K. B. Alici and E. Ozbay, Physica Status Solidi B 244, 1192 (2007).
[14] K. B. Alici and E. Ozbay, J. Appl. Phys. 101, 083104 (2007).
[15] K. B. Alici, A. E. Serebryannikov, and E. Ozbay, J. Electromagn. Waves Appl. 24, 1183 (2010).
[16] H. Zhang, Y.-Q. Li, X. Chen, Y.-Q. Fu, and N.-C. Yuan, IEEE Trans. Antennas Propag. 57, 3352 (2009).
[17] S. Cumhur Basaran and Y. E. Erdemli, Microwave Opt. Technol. Lett. 51, 2685 (2009).
[18] J. Zhu, M. Antoniades, and G. Eleftheriades, IEEE Trans. Antennas Propag. 58, 1031 (2010).
[19] J. Gemio, J. Parron, P. de Paco, G. Junkin, J. Marin, and O. Menendez, J. Electromagn. Waves Appl. 24, 241 (2010).
[20] M. Barbuto, F. Bilotti, and A. Toscano, Int. J. RF Microwave Comput.-Aided Eng. 22, 552 (2012).
[21] Y. Dong, H. Toyao, and T. Itoh, IEEE Trans. Antennas Propag. 60, 772 (2012).
[22] H. Stuart and A. Pidwerbetsky, IEEE Trans. Antennas Propag. 54, 1644 (2006).
[23] Y. Dong and T. Itoh, Proc. IEEE 100, 2271 (2012).
[24] R. Ziolkowski, P. Jin, and C.-C. Lin, Proc. IEEE 99, 1720 (2011).
[25] G. Skahill, R. Rudish, and J. Piero, in Proceedings of the Antenna Applications Symp. (Allerton, IL, 1998), pp. 214–231.
[26] A. Kaya and E. Yuksel, IEEE Trans. Antennas Propag. 55, 1275 (2007).
[27] S. Sussman-Fort and R. Rudish, IEEE Trans. Antennas Propag. 57, 2230 (2009).
[28] M. Barbuto, A. Monti, F. Bilotti, and A. Toscano, “Design of a non-Foster actively loaded SRR and application in metamaterial-inspired components,” IEEE Trans. Antennas Propag. (to be published), doi: 10.1109/TAP.2012.2228621.
[29] E. D. Isaacs, P. M. Platzman, and J. T. Shen, “Resonant antennas,” U.S. patent 6,661,392 (December 9, 2003).
[30] J. Pendry, A. Holden, D. Robbins, and W. Stewart, IEEE Trans. Microwave Theory Tech. 47, 2075 (1999).
[31] F. Falcone, T. Lopetegi, J. Baena, R. Marques, F. Martin, and M. Sorolla, IEEE Microw. Wirel. Compon. Lett. 14, 280 (2004).
[32] F. Falcone, T. Lopetegi, M. A. G. Laso, J. D. Baena, J. Bonache, M. Beruete, R. Marqu’es, F. Martin, and M. Sorolla, Phys. Rev. Lett. 93, 197401 (2004).
[33] H. Odabasi, F. L. Teixeira, and D. O. Guney, Electrically Small, Complementary Electric-Field-Coupled Resonator Antennas, J. Appl. Phys. 113, 084903 (2013). URL: http://link.aip.org/link/?JAP/113/084903
[34] D. Schurig, J. J. Mock, and D. R. Smith, Appl. Phys. Lett. 88, 041109 (pages 3) (2006).
[35] T. H. Hand, J. Gollub, S. Sajuyigbe, D. R. Smith, and S. A. Cummer, Appl. Phys. Lett. 93, 212504 (pages 3) (2008).