Page 85 - ITU Kaleidoscope 2016
P. 85

SPACE DIVISION MULTIPLEXING TECHNOLOGY:
                         NEXT GENERATION OPTICAL COMMUNICATION STRATEGY

             Kazuhide NAKAJIMA, Takashi MATSUI, Kotaro SAITO, Taiji SAKAMOTO, and Noriyuki ARAKI

                             Access Network Service Systems Laboratories, NTT Corporation
                                  1-7-1, Hanabatake, Tsukuba, Ibaraki, 305-0805, Japan


                              ABSTRACT                        networks. We then investigate SDM technology in relation
                                                              to optical  fibre cable. Here, we clarify the potential of a
           Space division multiplexing (SDM) is expected to be a key   multi-core fibre (MCF) as an SDM medium. After that we
           technology both for dealing with the future capacity crunch   discuss key stages in the deployment of MCF technology.
           facing  traditional  single-mode fibre (SMF)  and  for   We also introduce some key technologies described in the
           realizing a sustainable optical network that can   latest reports. Finally, we show that  MCF based  SDM
           accommodate  the  various  data streams originating from,   optical wiring is ready for discussion as the next generation
           for  example, future 5G communication, the Internet of   optical communication standard for the near future
           things (IoT), and machine to machine (M2M) networks.
           This  paper  describes  the  potential of SDM as regards             2. WHY SDM?
           optical  fibre and cable technology.  We  focus on the
           potential of multi-core fibre (MCF), and  investigate the   The worldwide spread of FTTH and mobile communication
           reality of  MCF based  SDM optical wiring as the first   has increased data capacity at a rate of a few tens of percent
           example of an SDM application taking the latest research   per year. The upcoming 5G service requires a wider
           and development into consideration. Finally, we show that   bandwidth, and the growing communication  network  has
           MCF based  SDM  optical fibre cable will be a  promising   created  various  data streams including IoT, M2M, sensor
           technology  for  next  generation optical networks, and the   networks, and connected cars. Therefore, it is true that the
           key technology behind MCF based SDM optical wiring is   continuing  increase  in data transmission will cause a
           ready for discussion as the near future standard.   capacity  crunch  in  existing SMF since its maximum
                                                              transmission  capacity  is  limited to around 100 Tbit/s
               Keywords—  Space division multiplexing  (SDM);   because of the low loss and optically amplified transmission
           Optical fibre and cable;  Multi-core fibre (MCF); Optical   window [1]. In general terms, the  approaching  capacity
           connector                                          crunch requires either additional optical infrastructure or an
                                                              innovative transmission strategy. SDM can be considered a
                          1. INTRODUCTION                     fifth physical dimension that can be used with the traditional
                                                              dimensions of time, wavelength, frequency and polarization
           Data capacity demand has been increasing rapidly against   multiplexing technology [2]. Thus, it is easy to imagine that
           the  background  of  the  worldwide spread of fibre to the   SDM can be used as a candidate technology for overcoming
           home (FTTH)  and mobile networks.  The  imminent   the future capacity crunch.
           introduction  of 5G, the Internet of Things (IoT), and
           machine to machine (M2M) communications not only
           requires further capacity but also demands a flexible  and
           sustainable interface with a high-speed optical fibre link.
              Over the past ten years, space  division  multiplexing
           (SDM) technology has been investigated intensively mainly
           with  the  aim  of increasing the maximum transmission
           capacity in an optical fibre. This is because the capacity
           demand in the 2020s will potentially exceed the limitation
           imposed  by  conventional  single-mode  fibre  (SMF)  [1].
           SDM could be the key to realizing both ultra-large capacity
           transmission and to solving various problems with current
           and future optical networks.
              In  this paper, we investigate the potential of SDM   Figure 1.   Schematic  image  of    growing
           technology as a new strategy for realizing next generation   communication network. FTTH, mobile, 5G, IoT,  M2M,
           optical networks. In section 2, we will briefly review the   sensor network, connected car, and so on increase the data
           relationship between SDM technology and various    capacity continuously, and require additional interfaces with
           objectives that must be met by current and future optical   a high-speed optical link.




           978-92-61-20431-0/CFP1668P-ART © 2016 ITU      – 67 –                                   Kaleidoscope
   80   81   82   83   84   85   86   87   88   89   90