Page 106 - ITU Journal, Future and evolving technologies - Volume 1 (2020), Issue 1, Inaugural issue
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ITU Journal on Future and Evolving Technologies, Volume 1 (2020), Issue 1




                  20
                                                  °            with RIM with two different configurations in terms of
                                           RIM,   = 20
                                              b
                                                  °            beam width, and without RIM.
                                           RIM,   = 90
                                              b
                  15                       no RIM              As a future piece of work, a factor that we have not consid-
                 Capacity [Gbps]  10                           ered in this context is the presence of other sources and
                                                               interferences. We trust the integration of the RIM in the
                                                               system can improve the reduction of the interference im-
                  5                                            pact by properly addressing it. In order to account for this
                                                               point, we plan to extend the analytical model with the in-
                                                               terference factor and design RIM-based approaches that
                                                               reduce the impact of the interference.
                  0
                   0     100   200   300   400   500
                               Distance [m]
                                                               ACKNOWLEDGMENT
          Fig. 10 – Capacity of the system with a rate set to 1 Gbps, in case of (i) a
                                    ∘         ∘
          meta-surface with beam width       = 20 and       = 90 , and (ii) without  This work is partially supported by the Exploratory Ac-
          a meta-surface.
                                                               tion ETHICAM.
          tion that is computed in real time and without error. In-
          deed, in order to control the RIM and make it as a tunable
          and intelligent meta-surface, we need to include an intel-  REFERENCES
          ligent logic, potentially based on a machine learning (ML)
                                                                [1] A. Nemati, Q. Wang, M. Hong, and J. Teng, “Tunable
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                                                                    and reconfigurable meta-surfaces and metadevices,”
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                                                                    in Opto-Electronic Advances, 01, 180009, 2018.
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          needs to be calculated). ML approaches for systems based  [2] C. Liaskos, A. Tsioliaridou, S. Nie, A. Pitsillides, S.
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                                                                [3] C. Liaskos, A. Tsioliaridou, A. Pitsillides, S. Ioanni-
          much on the ideal performance of the system.
                                                                    dis, and I. F. Akyildiz, “Using any Surface to Realize
                                                                    a New Paradigm for Wireless Communications,” in
          7.  CONCLUSIONS                                           Communications of the ACM, vol. 61 no. 11, pp. 30-
                                                                    33, October 2018.
          In this paper, we presented a multifunctional reconfig-
          urable meta-surface based on the radiation pattern mod-  [4] C. Liaskos, S. Nie, A. Tsioliaridou, A. Pitsillides, S.
          ulation of the reflection coefficient. We designed a recon-  Ioannidis, and I. F. Akyildiz, “A New Wireless Com-
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                                ∘
          that allows to obtain a 180 -phase difference between ON  Meta-surfaces,” in IEEE Communications Magazine,
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          signed for multifunctional behavior such as coding and
          beam steering, considering a 10×10 meta-surface loaded  [5] L. La Spada, V. Loscrí, and A.M. Vegni, “Meta-Surface
                                                                    Structure Design and Channel Modelling for THz
          with PIN diodes.
                                                                    Band Communications,” in Proc. of INFOCOM 2019
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          idate the proposed RIM in a vehicular scenario, for data  band Terahertz Communication for 5G and Beyond
          transmission via the V2X mode. The instantaneous data     Networks (UBTCN 2019), April 29-May 2, Paris,
          rate has been obtained, as a function of the beam width,  France.
          the vehicle speed and the distance. As expected, the lower
                                                                [6] A. Taibi, A. Durant, V. Loscrí, A.M. Vegni, and L.
          the beam width is, the higher the data rate is; addition-
                                                                    La Spada, “Controlling Light by Curvilinear Meta-
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                                                                    Surfaces,” in Proc. of ACM Nanocom 2019, Septem-
          rate is. Same consideration occurs for the distance. In or-
                                                                    ber 25-27, 2019, Dublin, Ireland.
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          the vehicular communication system, we have derived the  [7] J. Dickmann et al., “Automotive radar the key tech-
          outage probability for a specific target QoS in terms of an  nology for autonomous driving: From detection and
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          based on the outage probability and we have compared      2016 IEEE Radar Conference (RadarConf), Philadel-
          both the outage and the capacity for a system equipped    phia, PA, 2016, pp. 1-6.





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