volume | PIER Journals

Abstract

We demonstrate that the future sixth generation (6G) radio links can be utilized for sub-THz frequency imaging using narrow beamwidth, high gain, lens antennas. Two different lenses, a bullet or hemispherical shape, were used in radio link setup (220-380 GHz) for an imaging application. Lenses performed with the gain of 28 dBi, 25 dBi, and narrowed the beamwidths of 1° and 2.5°. Plants were used as imaging objects, and their impacts on radio beams were studied. For assessment, the radio link path loss parameter was -48.5 dB, -53.2 dB, and -57.1 dB with the frequency 220 GHz, 300 GHz, and 330 GHz, respectively. Also, the impact of the radio link distance on the imaging was studied by 50 cm and 2 m link distances. In addition, the 3D image was acquired using the phase component of the image, and it showed the leaf surface roughness and the thickness, which was similar to the measured value.

1. "Final Acts WRC-19," ITU, http://handle.itu.int/11.1002/pub/813b5921-en (accessed Jul. 06, 2021).

2. Volakis, J., Antenna Engineering Handbook, 4th Edition, McGraw-Hill, 2007.
doi:10.1109/MWC.001.2000220

3. Barneto, C. B., S. D. Liyanaarachchi, M. Heino, T. Riihonen, and M. Valkama, "Full duplex radio/radar technology: The enabler for advanced joint communication and sensing," IEEE Wirel. Commun., Vol. 28, No. 1, 82-88, Feb. 2021, doi: 10.1109/MWC.001.2000220.
doi:10.1109/ACCESS.2021.3059488

4. Wild, T., V. Braun, and H. Viswanathan, "Joint design of communication and sensing for beyond 5G and 6G systems," IEEE Access, Vol. 9, 30845-30857, 2021, doi: 10.1109/ACCESS.2021.3059488.
doi:10.1109/ACCESS.2016.2639038

5. Paul, B., A. R. Chiriyath, and D. W. Bliss, "Survey of RF communications and sensing convergence research," IEEE Access, Vol. 5, 252-270, 2017, doi: 10.1109/ACCESS.2016.2639038.
doi:10.1109/JPROC.2011.2143650

6. Rappaport, T. S., J. N. Murdock, and F. Gutierrez, "State of the art in 60-GHz integrated circuits and systems for wireless communications," Proc. IEEE, Vol. 99, No. 8, 1390-1436, Aug. 2011, doi: 10.1109/JPROC.2011.2143650.
doi:10.1109/ACCESS.2019.2921522

7. Rappaport, T. S., et al. "Wireless communications and applications above 100 GHz: Opportunities and challenges for 6G and beyond," IEEE Access, Vol. 7, 78729-78757, 2019, doi: 10.1109/ACCESS.2019.2921522.

8. Rajatheva, N., et al. "White paper on broadband connectivity in 6G,", University of Oulu, White paper No. 10, 2020. Accessed: Feb. 17, 2021, Online, Available: http://urn./urn:isbn: 9789526226798.

9. De Lima, C., et al. "6G white paper on localization and sensing,", University of Oulu, White paper No. 12, 2020, Accessed: Feb. 17, 2021, Online Available: http://urn./urn:isbn:9789526226743.

10. Tan, D. K. P., et al. "Integrated sensing and communication in 6G: Motivations, use cases, requirements, challenges and future directions," 2021 1st IEEE International Online Symposium on Joint Communications Sensing (JCS), 1-6, Dresden, Germany, Feb. 2021, doi: 10.1109/JCS52304.2021.9376324.

11. "Hexa-X,", https://hexa-x.eu/, accessed Jul. 07, 2021.
doi:10.1109/TTHZ.2018.2851922

12. Song, Z., et al. "Temporal and spatial variability of water status in plant leaves by terahertz imaging," IEEE Trans. Terahertz Sci. Technol., Vol. 8, No. 5, 520-527, Sep. 2018, doi: 10.1109/TTHZ.2018.2851922.
doi:10.1109/IMWS3.2011.6061867

13. Etayo, D., et al. "THz imaging system for industrial quality control," 2011 IEEE MTT-S International Microwave Workshop Series on Millimeter Wave Integration Technologies, 172-175, Sitges, Spain, Sep. 2011, doi: 10.1109/IMWS3.2011.6061867.

14. Yamada, Y., N. Michishita, and S. Kamada, "Construction of wide angle beam scanning lens an- tenna and its applications," 2009 International Conference on Space Science and Communication, 41-46, Port Dickson, Malaysia, Oct. 2009, doi: 10.1109/ICONSPACE.2009.5352674.

15. Fernandes, C. A., E. B. Lima, and J. R. Costa, "Dielectric lens antennas," Handbook of Antenna Technologies, 1001-1064, Z. N. Chen, D. Liu, H. Nakano, X. Qing, and T. Zwick, Eds., Singapore, Springer, 2016, doi: 10.1007/978-981-4560-44-3 40.

16. Sauleau, R., C. A. Fernandes, and J. R. Costa, "Review of lens antenna design and technologies for mm-wave shaped-beam applications," 11th International Symposium on Antenna Technology and Applied Electromagnetics, ANTEM 2005, 1-5, St. Malo, Jun. 2005, doi: 10.1109/ANTEM.2005.7852157.
doi:10.2528/PIERL20060108

17. Kokkonen, M., M. Nelo, J. Chen, S. Myllymaki, and H. Jantunen, "Low permittivity environmentally friendly lenses for Ku band," Progress In Electromagnetics Research Letters, Vol. 93, 1-7, 2020.
doi:10.1049/el.2020.1875

18. Myllymaki, S., M. Teirikangas, and M. Kokkonen, "BaSrTiO3 ceramic-polymer composite material lens antennas at 220{330 GHz telecommunication applications," Electron. Lett., Vol. 56, No. 22, 1165-1167, 2020, doi: 10.1049/el.2020.1875.

19. Saleh, B. E. A. and M. C. Teich, Fundamentals of Photonics, 2nd Edition, Wiley-Interscience, Hoboken, N.J., 2007.
doi:10.1038/srep28114

20. Hsieh, Y.-D., et al. "Dynamic terahertz spectroscopy of gas molecules mixed with unwanted aerosol under atmospheric pressure using bre-based asynchronous-optical-sampling terahertz time-domain spectroscopy," Sci. Rep., Vol. 6, No. 1, 28114, Jun. 2016, doi: 10.1038/srep28114.
doi:10.1007/s10762-018-0482-6

21. Yamagiwa, M., et al. "Real-time amplitude and phase imaging of optically opaque objects by combining full-eld off-axis terahertz digital holography with angular spectrum reconstruction," J. Infrared Millim. Terahertz Waves, Vol. 39, No. 6, 561-572, Jun. 2018, doi: 10.1007/s10762-018-0482-6.
doi:10.1016/j.rse.2008.02.012

22. Feret, J.-B., et al. "PROSPECT-4 and 5: Advances in the leaf optical properties model separating photosynthetic pigments," Remote Sens. Environ., Vol. 112, No. 6, 3030-3043, Jun. 2008, doi: 10.1016/j.rse.2008.02.012.

Dr. Ali Ghavidel

Dr. Sami Myllymäki

Mr. Mikko Kokkonen

Dr. Nuutti Tervo

Dr. Mikko Nelo

Dr. Heli Jantunen