Page 226 - From Smart Grid to Internet of Energy

200 From smart grid to internet of energy

demands. The 4G and first reported results of fifth generation (5G) cellular
communication systems are showed that millimeter wave (mmWave) frequen-
cies may present new opportunities for wireless communication systems
because there exists a significant potential to attain higher data rates by exploit-
ing existing idle bandwidths in mmWave frequencies [55–57]. Unfortunately,
there exist various problems to be overcome by emerging communication stan-
dards. One of the most significant issues is insufficiency of RF spectrum for
current mobile communication systems since ultra-high frequency (UHF) bands
are thoroughly utilized. Another issue is high energy consumption of wireless
technologies. For example, a cellular phone network typically needs about 40–
50 MW power to maintain its operation [58]. The other important problems that
should be solved by next generations of cellular communication systems are
related to mobility, data rate, coverage, spectral efficiency, QoS and interoper-
ability issues of heterogeneous networks.
Later 4G communication systems were released in 2011, researchers have
started to research new technologies for cellular communication systems called
5G systems. It is waited that 5G communications systems will be standardized
by 2020s. Recently, ITU-R has published some recommendations for general
concepts of next generation cellular systems for 2020 and beyond [59]. These
recommendations are related to utilization situations and main requirements of
novel services such as wireless industry automation, SGs, augmented reality
(AR), e-health, traffic safety and efficiency, remote tactile control, and so on
[54, 59]. If new generation of cellular systems are compared with the 4G cellular
systems, it is predicted that 5G communication systems will present significant
developments. Some of these developments can be sorted out as 10-fold energy
efficiency, 25 times average cell throughput, 10-fold spectral efficiency and
data rates (i.e., 10 Gbps peak data rate for low-speed mobile systems and 1 Gbps
2
for high-speed mobile systems), and 1000 times system capacity per km .
Furthermore, this new generation system aims to support several application
circumstances such as communication in high-speed vehicles, 4K video stream-
ing without disconnection and so on, which could not be accomplished by the
previous generations [50]. Various services and applications to be experienced
by users through new generation cellular systems are illustrated in Fig. 5.12
[60]. There exist two essential trends directing expected scenarios. The first
one is that next generation communication systems will gather all wireless
systems under the same umbrella to enable data acquisition, observing and man-
aging of devices. For example, SG systems will be more efficient and powerful
since sensors, SMs and whole systems can communicate with each other over
high-speed wireless connection. In addition, IoT and M2M services will be
managed more effectively. The second expectation is related to big data that
is a result of growing connected sensors, devices and novel services and appli-
cations such as remote health check, ultra-high-definition video streaming, AR
and so on. Moreover, industry initiatives are determined major requirements of
5G cellular systems, which can be summarized as follows [51].