Performance Analysis and Design Considerations of the Near-Field-Focused Rotman Lens Antennas

Authors

  • Salem M. Otman Department of Electrical and Electronic Engineering Cyprus International University, Nicosia 99258, Northern Cyprus
  • Mehmet Kuşaf Department of Electrical and Electronic Engineering Cyprus International University, Nicosia 99258, Northern Cyprus
  • Abdullah Y. Öztoprak Department of Electrical and Electronic Engineering Cyprus International University, Nicosia 99258, Northern Cyprus

DOI:

https://doi.org/10.13052/2024.ACES.J.390601

Keywords:

Beamforming, near-field-focusing, Rotman lenses

Abstract

This study investigates the application of Rotman lens antennas in the near field. The design equations of these antennas have been derived in the near field and demonstrated to be highly effective. By considering specific examples, the shapes of the inner surfaces of these lens antennas have been analyzed and discussed, revealing how practically realizable lens surfaces can be designed. As these Rotman lenses are perfect at only three points in the near field, they exhibit phase errors at other points along a line connecting the three near-field focal points, resulting in deterioration of the near-field patterns. It has been shown that by selecting the lens parameters appropriately, these phase errors can be kept to a minimum, causing only minimal beam deterioration. Compared to far-field-focused Rotman lens antennas, near-field-focused Rotman lens antennas achieve significantly higher power levels, having 3.8 to 6.3 dB improvement for different beams of a 17-element array. The study has demonstrated the potential of Rotman lenses as multiple beamforming antennas for near-field applications.

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Author Biographies

Salem M. Otman, Department of Electrical and Electronic Engineering Cyprus International University, Nicosia 99258, Northern Cyprus

Salem M. Otman received his bachelor’s degree in Electrical and Electronic Engineering from Bright Star University, Albrega Libya, in 2003, and his master’s degree from Cyprus International University in 2018 in the same field. He is currently a Ph.D. student in the Department of Electrical and Electronic Engineering at Cyprus International University. His current research interests include planar antennas, arrays, and near-field-focusing of planar arrays.

Mehmet Kuşaf, Department of Electrical and Electronic Engineering Cyprus International University, Nicosia 99258, Northern Cyprus

Mehmet Kuşaf was born in Larnaca, Cyprus, in December 1973. He received the Ph.D. degree in Electrical and Electronic Engineering from Eastern Mediterranean University in 2005. From 2005 to 2006, he worked as Assistant Professor with the Department of Electrical and Electronics Engineering, European University of Lefke. His academic journey at Cyprus International University began in 2006 as an Assistant Professor, followed by his promotion to Associate Professor in 2009, and culminated as Professor position in 2019. He is currently serving as the Head of Electrical and Electronic Engineering Department. He is the author of many research articles published in esteemed journals. His research expertise includes computational electrodynamics, antennas, and power systems.

Abdullah Y. Öztoprak, Department of Electrical and Electronic Engineering Cyprus International University, Nicosia 99258, Northern Cyprus

Abdullah Y. Öztoprak earned his Ph.D. in Electrical and Electronic Engineering from University College London, University of London, UK, in 1977. He joined Eastern Mediterranean University (EMU) as an Assistant Professor in 1986, became an Associate Professor in 1988, and progressed to Professor in 1997. During his tenure at EMU, he held various leadership positions, including Chairman of the Department of Electrical and Electronic Engineering (1989-1992), Vice-Rector for Academic Affairs (1992-2003), and Rector (2009-2014). Professor Oztoprak’s research focuses on beam forming networks, Rotman lenses, microwave antennas, split-step finite-difference time-domain methods, and unconditionally stable finite-difference time-domain methods.

References

P. Nepa and A. Buffi, “Near-field-focused microwave antennas; near-field shaping and implementation,” IEEE Antenna and Propagation Magazine, vol. 59, no. 3, pp. 42-53, 2017.

A. Buffi, P. Nepa, and G. Manara, “Design criteria for near-field-focused planar arrays,” IEEE Antennas Propag. Mag., vol. 54, no. 1, pp. 40–50, Feb. 2012.

S. M. Mikki and Y. M. M. Antar, “A theory of antenna electromagnetic near field-Part I,” IEEE Transactions on Antennas and Propagation, vol. 59, no. 12, pp. 4691-4705, 2011.

S. M. Mikki and Y. M. M. Antar, “A theory of antenna electromagnetic near field-Part II,” IEEE Transactions on Antennas and Propagation, vol. 59, no. 12, pp. 4706-4724, 2011.

J. T. Loane III and S.-W. Lee, “Gain optimization of a near-field focusing array for hyperthermia applications,” IEEE Trans. on Microwave Theory and Techniques, vol. 37, no. 10, pp. 1629–1635, Oct. 1989.

F. Tofigh, J. Nourinia, M. Azarmanesh, and K. M. Khazaei, “Near-field focused array microstrip planar antenna for medical applications,” IEEE Antennas and Wireless Propagation Letters, vol. 13, pp. 951-954, 2014.

H. Chen, Z. Zhang, and J. Yu, “Near-field scattering of typical targets illuminated by vortex electromagnetic waves,” The Applied Computational Electromagnetics Society Journal (ACES), vol. 35, no. 2, pp. 129-134, Feb. 2023.

H. Chen, Z. Zhang, and J. Yu, “Resolution of near-field beamforming and its impact on NOMA,” IEEE Wireless Commun. Lett., vol. 13, no. 2, pp. 456-460, Feb. 2024.

F. Paredes, C. Herrojo, R. Escudé, E. Ramon, and F. Martin, “High data density near-field chipless-RFID tags with synchronous reading,” IEEE Journal of Radio Freq. Ident., vol. 4, no. 4, pp. 517-524, Dec. 2020.

S. H. Zainud-Deen, H. A. Malhat, and K. H. Awadalla, “Dielectric resonator antenna phased array for fixed RFID reader in near field region,” in Japan-Egypt Conference on Electronics, Communications and Computers, Alexandria, Egypt, pp. 102-107, 2012.

A. Buffi, A. A. Serra, P. Nepa, H. T. Chou, and G. Manara, “A focused planar microstrip array for 2.4 GHz RFID readers,” IEEE Transactions on Antennas and Propagation, vol. 58, no. 5, pp. 1536-1544, 2010.

Y. Wang, L. Shen, C. Huang, J. Zhu, and W. Tang, “Series-fed dipole array for near-field RFID application,” The Applied Computational Electromagnetics Society Journal (ACES), vol. 33, no. 11, pp. 1190-1195, Nov. 2018.

M. Bogosanovic and A. G. Williamson, “Microstrip antenna array with a beam focused in the near-field zone for application in noncontact microwave industrial inspection,” IEEE Transactions on Instrumentation and Measurement, vol. 56, no. 6, pp. 2186-2195, 2007.

S. Singh and S. P. Singh, “Microstrip slot antenna for hyperthermia applications,” in Applied Electromagnetic Conference (AEMC 2015), Guwahati, India, 18-21 Dec. 2015.

W. C. Choi, K. J. Kim, J. Kim, and Y. J. Yoon, “Compact microwave radiator for improving heating uniformity in hyperthermia system,” IEEE Antennas Wireless Propag. Lett., vol. 13, pp. 1345-1348, 2014.

W. C. Choi, S. Lim, and Y. J. Yoon, “Design of noninvasive hyperthermia system using transmit-array lens antenna configuration,” IEEE Antennas and Wireless Propagation Letters, vol. 15, pp. 857-860, 2016.

P. Nayeri, F. Yang, and A. Z. Elsherbeni, “Beam-scanning reflectarray antennas: An overview,” in USNC-URSI National Radio Science Meeting, Chicago, IL, July 2012.

L. Stark, “Microwave theory of phased-array antennas: a review,” Proc. the IEEE, pp. 1661-1701, 1974.

W. Rotman and R. F. Turner, “Wide-angle microwave lens for line source applications,” IEEE Trans. Antennas Propag., vol. AP-11, no. 6, pp. 623-632, Nov. 1963.

M. J. Maybell, K. K. Chan, and P. S. Simon, “Rotman lens recent developments 1994–2005,” in Proceedings of the 2005 IEEE Antennas and Propagation Society International Symposium, Washington, DC, 3-8 July 2005.

D. H. Archer and M. J. Maybell, “Rotman lens development history at Raytheon Electronic Warfare Systems 1967-1995,” in Proceeding of the IEEE Antennas and Propagation Society International Symposium, Washington, DC, pp. 31-34, 2005.

M. Sohail, R. Uyguroğlu, and A.Y. Öztoprak, “Scanning of the near-field focused beam by changing frequency,” The Applied Computational Electromagnetics Society Journal (ACES), vol. 38, no. 3, pp. 177-183, Mar. 2023.

P. Li, P. Li, P. Yang, Z. Kuang, and X. Luo, “Design of compact Rotman lens with wide-angle scanning using high permittivity substrate,” in 2021 International Applied Computational Electromagnetics Society (ACES-China) Symposium, Chengdu, China, 28-31 July 2021.

T. K. Vo Dai, T. Nguyen, and O. Kilic, “A non-focal Rotman lens design to support cylindrically conformal array antenna,” The Applied Computational Electromagnetics Society Journal (ACES), vol. 33, no. 2, pp. 240-243, Feb. 2018.

R. Uyguroğlu, A. Y. Öztoprak, and C. Ergün, “Improved phase performance for Rotman lens,” International Journal of RF and Microwave Computer-Aided Engineering, vol. 23, no. 6, pp. 634-638, Oct. 2013.

H.-T. Chou and D. Torrungrueng, “Development of 2-D generalized tri focal Rotman lens beamforming network to excite conformal phased arrays of antennas for general near/far-field multi-beam radiations,” IEEE Access, vol. 9, pp. 49176–49188, 2021.

A.K. Vallappil, M. K. A. Rahim, B. A. Khawaja, N. A. Murad, M. M. Gajibo, “Butler matrix based beamforming networks for phased array antenna systems: A comprehensive review and future directions for 5G applications,” IEEE Access, vol. 9, pp. 3970-3987, 2021.

R. Uyguroğlu and A. Y. Niazi, “Designing microstrip transitions into parallel plate regions using the FDTD method,” Microwave and Optical Technology Letters, vol. 22, pp. 81-84, 1999.

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Published

2024-06-30

How to Cite

[1]
S. M. Otman, M. Kuşaf, and A. Y. Öztoprak, “Performance Analysis and Design Considerations of the Near-Field-Focused Rotman Lens Antennas”, ACES Journal, vol. 39, no. 06, pp. 470–477, Jun. 2024.

Issue

2024: Vol 39 Iss 6

Section

General Submission

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