Space Division Multiplexing

This literature review provides an in-depth analysis of the concept and importance of space division multiplexing (SDMA) in communication channels. It discusses the fundamental working of SDMA, its advantages and limitations, and its role in improving the capacity of communication channels. The review also highlights the findings and results of previous research studies on SDMA.

Space Division Multiplexing

LITERATURE REVIEW 1
Table of Contents
Literature review...................................................................................................................................2
Preamble...........................................................................................................................................2
Main review.......................................................................................................................................3
Discussion/conclusion...........................................................................................................................7
References.............................................................................................................................................8

LITERATURE REVIEW 2
Literature review
Preamble
Space division multiplexing is defined as the channel access technique which is based on
the creating parallel spatial pipes next to larger capacity pipes with the help of the
multiplexing process. It is a part of the multiplexing technique where numbers of signals
can be transmitted from sources to the receiver and it is used in the communication
techniques for exchanging information from one place to another. The researchers
selected this topic because it is one of the common topics for investigation and provide
complete information about the communication channels used in daily life
communications. From this literature review, it is expected to learn the fundamental
concept of space division multiplexing and their importance in the communication
processes.
There are the following research questions will be discussed in this literature review
section:
 What is space division multiplexing?
 How space division multiplexing technique works and what is the role of this
technique in the communication?
 What are the advantages and limitations of space division multiplexing
technique?
All these research questions will be discussed in this literature review and critically
analyse the fundamental concept of space division multiplexing. The major objective of
this research study is to gain understanding about space division multiplexing and
analyse the working principle of the SDMA technique. The space division multiplexing is
an advanced version of the CDMA technique where space is divided into numbers of
sections and users uses these spaces for communication purpose. The space division
multiplexing operates by dividing the space into various kinds of sections which can
help consumers for reusing both time and frequency. According to my opinion, this
topic is related to communication technologies and it is a part of multiplexing technique
that multiplies numbers of input signals at a time and transfers these signals from the
transmitter to a receiver using communication channels.

LITERATURE REVIEW 3
Main review
The space division multiplexing is one of the common topics for research and many
investigators provided their views on this topic. This literature review focuses on the
fundamental concept of the SDMA technique and analyses the results and findings
obtained by previous researchers. This literature also identifies the key aspects related
to the research topic and reduces the research gaps associated with previous
investigations.
According to Amaya, et al., (2014) SDMA is defined as the multiplexing technique in
which physical separation of the antenna is utilized for providing simultaneously
various kinds of data streams [1]. This research paper highlighted the key factors linked
with the space division multiplexing and provided in-depth analysis research topic.
From this paper it has been found that SDMA is one effective technique that has the
ability for increasing the capacity of communication channels. The researchers argued
that it is a kind of process by which optical transmission media are physically separated
by space for controlling and managing the separations of channels.
Leon-Saval, et al., (2014) identified that there are various kinds of methods by which
capacity of optical transmission can be increased such as modulation, polarization and
frequency division [3]. In this research paper, the authors used space division
multiplexing technique for improving the overall capability of transmission channels.
After critically analysing this research article it has been identified that there are major
two processes by which spatial separation of fibre cab be achieved, for example, few
mode fibres and multi core fibre. In the case of few more fibre the size and the refractive
index of the fibre core is selected but in the multi core fibre there are several cores
involves during communication process [14]. This research paper provided only
theoretical information about the research topic which creates a research gap between
information and research topic. But this literature review provides an in-depth analysis
of the research topic and reduces such kind of research gaps by analysing viewpoints of
other researchers on the SDMA technique.
According to Jain, et al., (2014) SDMA is a kind of technique by which radio, metallic and
optical transmission media are physically divided with the help of waveguides or
insulation [2]. In order to improve the effectiveness of the paper, the authors conducted
a literature review and provided relevant facts about the SDMA technique. In such kind

LITERATURE REVIEW 4
of technique, both time and frequency are controlled with the help of optical fibre
communication. The researcher identified that several passive optical network
implementations employ SDMA technique with the downstream transmission that
occurs over one fibre of a duplex fibre optic cable. The authors also found that the
CDMA is very less efficiency technique due to which information communication
technology developed SDMA process that has the capability for improving the overall
performance of the system.
Li, Bai, Zhao and Xia, (2014) described that the SDMA is a kind of multiplexing technique
for optical data transmission where numbers of spatial channels are used during
communication process [4]. This journal paper highlighted the applications of space
division multiplexing technique and provided complete information about working of
the SDMA technique. The major drawback of this research paper is that the authors did
not involve the opinions of other authors and provided brief information about the
research topic.
From this research paper, it has been identified that the SDMA technique is used in the
long haul communication for example submarine communication cables. According to Li
and Wang, (2014) in order to satisfy the exponential increment of data traffic, long haul
optical communication networks a new technique has been developed that is SDMA [5].
The fundamental concept of the SDMA technique can be used for long distance
communication purpose because it reduces distortions and losses by improving the
capacity of the system.
The researchers suggested that the SDMA technique can be implemented by
transferring traffic signals over consumer WDM systems. It is observed that the space
division technique also provide a way for reusing the time and frequency allocated to
the particular person. After analysing this research paper it has been found that the
SDMA technique is more reliable and flexible rather than FMDA and CDMA due to which
many communication organizations adopted the SDMA technique. in order to smoothly
upgrade WDM system to space division multiplexing, there are several key factors
involves, for example, optical amplifier, integrated transponders and their interfacing,
splices and connectors and many more.

LITERATURE REVIEW 5
Matsuo, et al., (2016) argued that the SDMA technique can be used for parallel
connection technology and fibre installation with spliced sections [6]. The researchers
conducted a literature review and evaluated that the space division multiplexing
technique can be utilized in tandem with another multiplexing access techniques for
example TDM and WDMA. In order to improve the effectiveness of the paper the
researcher used the results of previous studies and highlighted the drawbacks linked
with the SDMA technique. This research papers shows the importance of the SDMA
technique in the field of communication channels and supported evidence with real
world examples.
According to Muhammad, Zervas and Forchheimer, (2015), the SDMA technique allows
propagation of numbers of optical channels inside the core of a single fibre as a purpose
of location [7]. It is observed that the space division multiplexing the more secure and
reliable technique that reduces the rate of cross talk by enhancing the capacity of the
communication system. The authors argued that the SDMA channels follow helical paths
inside the core of a single fibre where every channel is confined to a dedicated radial
distance from the origin of the optical fibre. The value of the electric field at the centre
of the optical fibre is very less due to the formation of optical vortices and higher helical
paths. It is identified that the fundamental working of the SDMA technique does not
depend on the wavelength of the input signal and put simply the ring location of an SDM
output for reducing the cross talks and distortions.
From this journal paper, it has been found that if the output of SDMA is independent of
the wavelength of the input then an easy architecture can be designed and implement as
per the SDMA’s properties. According to Nelson, et al., (2014) the multiple inputs and
multiple outputs in SDMA mode can deliver a huge spectral efficiency gain without
improving the value of power [8]. From this paper, it has been analysed that the SDMA
technique introduced more than three decades ago and it is one of the advanced
multiplexing technique rather than CDMA and FDMA.
The general form of the SDMA technique is completely depended on the various kinds of
SDMA channels used in the systems and the effective area. However, the potential of
space division multiplexing lies in its capability to break the nonlinear Shannon limit of
SC-SM process. It is evaluated that the low level SDM transmissions have delivered a
threefold as compared to the SC-SM transmission system. The fundamental principle of

LITERATURE REVIEW 6
space division multiplexing is applicable for optical communication in both guided wave
and free space. Such kind of technique also involves the MIMO concept in order to
reduce the rate of cross talk from the communication channel.
From a recent study conducted by Rademacher and Petermann (2016) identified that
the SDMA technique using MCFs and FMFs are more effective rather than another kind
of SDM and they have the ability for reducing the overall cost of fibre optic transmission
[9]. The space division multiplexing of two numerous varieties can be employed to
transmit the data or information from one source to another. The researcher argued
that mode division multiplexing is one of the first technique based on the working
principle of space division multiplexing.
The other technique utilized in the field of SDMA is core multiplexing by which single
fibre can be designed and implanted more effectively. Ren, et al., (2016) identified that
the space division multiplexing is a straightforward solution which can be used for large
distance communication [10]. In the case of the SDMA technique the single fibre is
replaced with the numbers of fibres which are interconnected in the parallel
connections.
Moreover, many consumers use this technique for both short and long distance
communication due to their larger flexibility and reliability. The main drawback of the
SDMA technique is that it is more costly rather than other and cost of equipment
depends on the distance between transmitter and receiver. From the recent study it has
been found that the space division multiplexing increased the overall capacity of the
communication channels by 10 times and reduce the problem of cross talk by 70%.
There are several advantages of SDMA technique, for example, more reliable, easy to
design and implement, larger scalability, and can be used for long distance
communication.
All these key features are described by the researchers and analysed that issues linked
with previous multiplexing techniques can be resolved by using the SDMA technique.
According to Saridis, et al., (2015) the space division multiplexing is one of the best
techniques which can be utilized for managing the medium access for wireless sensor
networks [11]. The researchers also argued that the SDMA cannot be utilized in the field
of isolation because it uses a combination of one or two multiplexing techniques for

LITERATURE REVIEW 7
example TDMA, FDMA and CDMA. Moreover, space division technique needs careful
selection of zones for every transmitter and it provides accurate information which is
transferred from transmitter to receiver. Moreover, the space division multiplexing
enables effective infrastructure utilization and large scalability and hardware sources
are effectively utilized in the development of the SDMA channel.
The main key feature of space division multiplexing is that it combines the various kinds
of multiplexing technique in order to reuse the time and frequency of signals. The
researcher concluded that the SDMA technique works well and effective with slow voice
data or information signals but it is also useful for compressed video and other large
speed data communication. In order to improve the efficiency of the communication
channel the SDMA focus on the channels and mediums used in the communication
system and use optical fibre channels [13]. The other advantage of this communication
technology is that it also reduces the complexity of the system due to which many
consumers use this approach for sending and receiving signals from one location to
another.
Discussion/conclusion
From the above discussion, it has been found that the space division multiplexing
technique is the very best approach that has the ability for reducing the complexity of
the communication system [12]. The above literature review is completely based on the
fundamental working of the SDMA technique and it also fulfilled the research questions
of this study. As compared with the expectation the above literature review section
provided in-depth analysis by which readers can improve their skills and experience in
the field of communication channels. The major research gap in the literature review is
that the researchers did not compare the SDMA technique with other multiplexing
technique.
According to my opinion, the above literature review achieved the aims and objectives
of this research study and I am satisfied with the data and information involved in the
literature review. I did not find any surprising data or information and all these facts
and evidence. This research paper discussed the concept of the SDMA technique and
highlighted the importance of this technique in communication channels.

LITERATURE REVIEW 8
References
[1]. N., Amaya, S., Yan, M., Channegowda, B.R., Rofoee, Y., Shu, M., Rashidi, Y., Ou, E.,
Hugues-Salas, G., Zervas, R. Nejabati and, D., Simeonidou, “Software defined
networking (SDN) over space division multiplexing (SDM) optical networks:
features, benefits and experimental demonstration,”
Optics express, vol. 22, no. 3,
pp.3638-3647, 2014.
[2]. S., Jain, V.J.F., RancanKo, T.C., May-Smith, P., Petropoulos, J.K. Sahu and, D.J.,
Richardson, “Multi-element fibre technology for space-division multiplexing
applications,"
Optics express, vol. 22, no. 4, pp.3787-3796, 2014.
[3]. S.G., Leon-Saval, N.K., Fontaine, J.R., Salazar-Gil, B., Ercan, R. Ryf and, J., Bland-
Hawthorn, “Mode-selective photonic lanterns for space-division
multiplexing,”
Optics express, vol. 22, no. 1, pp.1036-1044, 2014.
[4]. G., Li, N., Bai, N. Zhao and, C., Xia, “Space-division multiplexing: the next frontier
in optical communication,”
Advances in Optics and Photonics, vol. 6, no. 4,
pp.413-487, 2014.
[5]. S. Li and, J., Wang, “A compact trench-assisted multi-orbital-angular-momentum
multi-ring fibre for ultrahigh-density space-division multiplexing (19 rings× 22
modes), "
Scientific reports, vol. 4, no. 2, p.3853, 2014.
[6]. S., Matsuo, K., Takenaga, Y., Sasaki, Y., Amma, S., Saito, K., Saitoh, T., Matsui, K.,
Nakajima, T., Mizuno, H. Takara and, Y., Miyamoto, “High-spatial-multiplicity
multicore fibers for future dense space-division-multiplexing systems,”
Journal
of Lightwave Technology, vol. 34, no. 6, pp.1464-1475, 2016.
[7]. A., Muhammad, G. Zervas and, R., Forchheimer, “Resource allocation for space-
division multiplexing: optical white box versus optical black box networking,”
Journal of Lightwave Technology, vol. 33, no. 23, pp.4928-4941, 2015.
[8]. L.E., Nelson, M.D., Feuer, K., Abedin, X., Zhou, T.F., Taunay, J.M., Fini, B., Zhu, R.,
Isaac, R., Harel, G. Cohen and, D.M., Marom, “Spatial superchannel routing in a
two-span ROADM system for space division multiplexing,”
Journal of Lightwave
Technology, vol. 32, no. 4, pp.783-789, 2014.
[9]. G. Rademacher and, K., Petermann, “Nonlinear Gaussian noise model for
multimode fibres with space-division multiplexing,”
Journal of Lightwave
Technology, vol. 34, no. 9, pp.2280-2287, 2016.

LITERATURE REVIEW 9
[10]. Y., Ren, L., Li, Z., Wang, S.M., Kamali, E., Arbabi, A., Arbabi, Z., Zhao, G., Xie,
Y., Cao, N. Ahmed and, Y., Yan, “Orbital angular momentum-based space division
multiplexing for high-capacity underwater optical communications,”
Scientific
reports, vol. 6, no. 2, p.33306, 2016.
[11]. G.M., Saridis, D., Alexandropoulos, G. Zervas and, D., Simeonidou, “Survey
and evaluation of space division multiplexing: From technologies to optical
networks,”
IEEE Communications Surveys & Tutorials, vol. 17, 4, pp.2136-2156,
2015.
[12]. H. Tode and, Y., Hirota, “Routing, spectrum and core assignment for space
division multiplexing elastic optical networks,” In
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Telecommunications Network Strategy and Planning Symposium (Networks),
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[13]. R.G.H., Van Uden, R.A., Correa, E.A., Lopez, F.M., Huijskens, C., Xia, G., Li, A.,
SchuQlzgen, H., De Waardt, and, C.M., Okonkwom, “Ultra-high-density spatial
division multiplexing with a few-mode multicore fibre,”
Nature Photonics, vol. 8,
no. 11, p.865, 2014.
[14]. P.J., Winzer, “Spatial multiplexing: The next frontier in network capacity
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