Joshua Anderson Kai Johnson Cody Satterlee Andrew Lynch Benjamin D. Braaten* ECE Department

A Reduced Frequency Printed Quasi-Yagi Antenna Symmetrically Loaded with Meander

Open Complementary Split Ring Resonator (MOCSRR) Elements

Joshua Anderson

Kai Johnson

Cody Satterlee

Andrew Lynch

Benjamin D. Braaten*ECE Department

North Dakota State University

Fargo, ND, USA.

APPLIED ELECTROMAGNETICS LAB

NORTH DAKOTA STATE UNIVERSITY

1) Introduction and Background

2) The Reduced frequency Quasi-Yagi Antenna

3) Measurement and Simulation Results

4) Discussion and Guidelines

5) Conclusion

Topics

NDSU : APPLIED ELECTROMAGNETICS LAB

Introduction and Background

[1] A. Velez, F. Aznar, J. Bonache, M. C. Valazquez-Ahumada, J. Martel and F. Martin, “Open complementary split ring resonators (OCSRRs) and their application to wideband CPW band pass filters,” IEEE Microwave and Wireless Component Letters, vol. 19, no. 4, pp. 197-199, Apr. 2009.

The open complementary split ring resonator (OCSRR) element [1]:



[2] B. D. Braaten, “A novel compact UHF RFID tag antenna designed using series connected open complementary split ring resonator (OCSRR) particle,” IEEE Transactions on Antennas and Propagation, vol. 58, no. 11, Nov. 2010, pp. 3728-3733.

The OCSRR element has been used to design small resonant antennas [2]:

Introduction and Background


Introduction and BackgroundThe meander open complementary split ring resonator (MOCSRR)

element [3]:

[3] B. D. Braaten and M. A. Aziz, “Using meander open complementary split ring resonator (MCOSRR) particles to design a compact UHF RFID tag antenna,” IEEE Antenna and Wireless Propagation Letters, vol. 9, 2010, pp. 1037-1040.


Introduction and BackgroundCPW structure used to measure the MOCSRR element:


Introduction and BackgroundPrinted MOCSRR element: S-parameters [4]:

Leq = 9.25 nHCeq = 5.1 pFfo = 735 MHz

[4] B. D. Braaten, M. A. Aziz, M. J. Schroeder and H. Li, “Meander open complementary split ring resonator (MOCSRR) particles implemented using coplanar waveguides,” Proceedings of the IEEE International Conference on Wireless Information Technology and Systems, Honolulu, Hawaii, Aug. 28 – Sep. 3, 2010.


Reduced Frequency Quasi-YagiA = 131.4 mmB = 145.98 mma = 22.27 mmb = 17.7 mmc = 1.3 mmd1 = 52.0 mmf = 40.98 mmi = 66.0 mmj = 12.0 mmk = 41.0 mm

m = 5.8 mmn = 9.08 mmu = 4.45 mmα = 48.28 mmβ = 15.91 mm

Substrate:Thickness:

1.27 mmPermittivity:

10.2


Reduced Frequency Quasi-Yagi

W = 6.88 mmH = 6.73 mmd2 = 2.45 mmg = 0.22 mmh = 4.53 mmp = 0.26 mmq = 0.32 mmr = 1.94 mms = 0.17 mmt = 0.27 mmv = 0.19 mm

Leq = 5.25 nHCeq = 5.6 pFfo = 2.2 GHz

Approx. twice the operating frequency.


Measurement and Simulation Results

Original unloaded quasi-yagi antenna [5]. New loaded quasi-yagi antenna.

[5] S. Chen and P. Hsu, “Broadband microstrip-fed modified quasi-yagi antenna,” Wireless Communications and Applied Computational Electromagnetics, Aug. 2005, pp. 208-211.



Closer image of the element.



Measuring the original quasi-yagi antenna. Operating frequency of 1.2 GHz.



Measuring the loaded quasi-yagi antenna.

35% lower operating frequency Simulated: 735 MHzMeasured: 765 MHz.



x-z plane at 735 MHz y-z plane at 735 MHz

• Simulated gain at 1.18 GHz was 4.1 dBi (unloaded antenna)• Simulated gain at 735 MHz was -5.5 dBi (loaded antenna)


Discussion and Guidelines

The input impedance of the loaded and unloaded dipole above was finally computed:

• At 800 MHz• Zeq1 = 17.2 – j97.0 Ω (without loading elements)• Zeq2 = 104.0 + j126.0 Ω (with loading elements)• Zeq= 102 Ω at 800 MHz (MOCSRR element)• Im(Zeq1 - Zeq2 ) = Im(ΔZ) ≈ 233.0 Ω ≈ 2Zeq

1) Intro. and background on the MOCSRR elements was presented.

2) The reduced frequency Quasi-Yagi antenna was introduced.

3) Measurement and simulation results were compared.

4) Initial discussion and guidelines on loading the antenna with MOCSRR elements was presented.

Conclusion


Thank you for listening!

Questions?


Documents

Joshua Anderson Kai Johnson Cody Satterlee Andrew Lynch Benjamin D. Braaten* ECE Department