Page 102 - ITU Journal Future and evolving technologies Volume 2 (2021), Issue 6 – Wireless communication systems in beyond 5G era
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ITU Journal on Future and Evolving Technologies, Volume 2 (2021), Issue 6




          6.   CONCLUSION                                      [5]   T. J. Cui, M. Q. Qi, X. Wan, J. Zhao, and Q. Cheng,
                                                                     "Coding metamaterials digital metamaterials
          In  this  paper,  with  the  aim  of  improving  the       and programmable metamaterials,"  Light Sci.
          potential  of  wireless  communications  using             Appl., vol. 3, p. e218, Oct. 2014.
          massive  distributed  IRS  reflectors  in  the  coming
          beyond 5G era, we clarified by both simulation and   [6]   S.  V.  Hum  and  J.  Perruisseau-Carrier,
          experiment  the  effectiveness  of  the  ON/OFF  IRS       "Reconfigurable  reflectarrays  and  array
          reflectors  selection  method  deployed  in  a             lenses for dynamic antenna beam control: A
          distributed manner in an indoor LOS environment.           review,"  IEEE Trans. Antennas Propag., vol. 62,
          We formulated this combination of IRS reflectors as        no. 1, pp. 183-198, Jan. 2014.
          an  optimization  problem  of  maximizing  the       [7]   C. Liaskos, S. Nie, A. Tsioliaridou, A. Pitsillides,
          receiver’s  channel  capacity  while  minimizing           S.  Ioannidis,  and  I.  Akyildiz,  "A  novel
          interference  on  the  interfered  receiver  and           communication  paradigm  for  high  capacity
          proposed a method for solving this problem at high         and  security  via  programmable  indoor
          speed  using  a  general-purpose  solver.  We  also        wireless  environments  in  next  generation
          proposed in combination with the above a method            wireless systems,"  Ad Hoc Netw., vol. 87, pp.
          for extracting candidate IRS reflectors by clustering      1-16, May. 2019.
          so  as  to  decrease  computational  time  while
          maintaining performance.                             [8]   C. Liaskos, S. Nie, A. Tsioliaridou, A. Pitsillides,
                                                                     S.  Ioannidis,  and  I.  Akyildiz,  "Realizing
          The  results  of  the  proposed  method  by  a             wireless  communication  through  software-
          combination of IRS reflectors showed that desired          defined hypersurface environments," in Proc.
          channel capacity could be improved beyond that of          IEEE  19th  Int.  Symp.  ‘World  Wireless  Mobile
          SISO  communication  without  IRS  reflectors  while       Multimedia Netw.’ (WoWMoM), pp. 14-15, Jun.
          maintaining the interference level on an interfered        2018.
          receiver  below  a  certain  threshold.  It  was  also
          shown that the proposed clustering method could      [9]   C. Liaskos, S. Nie, A. Tsioliaridou, A. Pitsillides,
          speed  up  processing  by  approximately  10  times        S. Ioannidis, and I. Akyildiz, "A new wireless
          compared  with  a  method  for  finding  a  solution       communication paradigm through software-
          through  an  exhaustive  search  and  that  the  worst     controlled  metasurfaces,"  IEEE  Commun.
          value  for  the  obtained  channel  capacity  could  be    Mag., vol. 56, no. 9, pp. 162-169, Sep. 2018.
          significantly improved from 0 to 2.4 bit/s/Hz. The   [10]  M.  Iwabuchi,  T.  Murakami,  R.  Ohmiya,  T.
          proposed  method  was  also  effective  for  real          Ogawa, Y. Takatori, Y. Kishiyama, and T. Asai,
          channels acquired by experiments.                          "[Invited]  Intelligent  Radio-Wave  Design:

                                                                     Distributed  Intelligent  Reflecting  Surface
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