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L. Stobbe et al.
and network densification. The following section discusses some environmentally
relevant research topics related to these 5G technologies. This discussion of the
theoretical interaction between certain technology options and environmental implications are important in the modelling process for creation of application scenarios.
As mentioned before, the multi-level model is intended for the use as an analytic
tool.
15.5.1 Multi-connectivity and C-RAN
In order to increase coverage, mobile data traffic capacity, and latency, 5G standardization has focused not only on a completely new radio technology (NR) but
also on mechanisms to integrate different radio access technologies (Multi-RAT)
into collaborative network or Cooperative Multi-Point systems (CoMP) for highly
efficient spectrum sharing. These technologies, although providing a considerable
performance improvement, are expected to require a considerable higher computation effort by the baseband unit (BBU) and mobility management entity (MME) of the
core network. The question of where within the network this calculation takes place
ultimately determines how energy and resource efficient it is. There are multiple
options. The baseband unit could be positioned as in current LTE networks very
close to the antenna unit or further upstream in the metro edge or even the core
network. This scenario would require considerable more bandwidth in the fronthaul
(in the transport network). A computation of this baseband processing and control
signaling within larger data centers (further away from the antenna site) provides
a good energy efficiency potential. Larger data center provide the option of higher
utilization of existing hardware, reduction of redundancy, and typically more efficient
cooling and power supply (better PuE).
The research question in this context is; where is the best position for the BBU
and the MME in the network.
15.5.2 Massive MIMO and Beamforming
One strategy to improve spectral efficiency is basically to increase the number
antennas and channels. Massive MIMO is an antenna technology that achieves very
high data transfer rates and coverage by using tens (32, 64) and hundreds (128, 256)
of antennas per sector in parallel. Additional antennas create more channels and help
to focus the energy when sending and receiving signals. The transmission power is
reduced in this way and the data rate increases. Also, link reliability improves as
Massive MIMO allows greater degrees of freedom in the selection of uplink and
downlink data streams. This in turn allows extended interference suppression. By
combining and synchronizing the active antennas a focused beams can be created
L. Stobbe et al.
and network densification. The following section discusses some environmentally
relevant research topics related to these 5G technologies. This discussion of the
theoretical interaction between certain technology options and environmental implications are important in the modelling process for creation of application scenarios.
As mentioned before, the multi-level model is intended for the use as an analytic
tool.
15.5.1 Multi-connectivity and C-RAN
In order to increase coverage, mobile data traffic capacity, and latency, 5G standardization has focused not only on a completely new radio technology (NR) but
also on mechanisms to integrate different radio access technologies (Multi-RAT)
into collaborative network or Cooperative Multi-Point systems (CoMP) for highly
efficient spectrum sharing. These technologies, although providing a considerable
performance improvement, are expected to require a considerable higher computation effort by the baseband unit (BBU) and mobility management entity (MME) of the
core network. The question of where within the network this calculation takes place
ultimately determines how energy and resource efficient it is. There are multiple
options. The baseband unit could be positioned as in current LTE networks very
close to the antenna unit or further upstream in the metro edge or even the core
network. This scenario would require considerable more bandwidth in the fronthaul
(in the transport network). A computation of this baseband processing and control
signaling within larger data centers (further away from the antenna site) provides
a good energy efficiency potential. Larger data center provide the option of higher
utilization of existing hardware, reduction of redundancy, and typically more efficient
cooling and power supply (better PuE).
The research question in this context is; where is the best position for the BBU
and the MME in the network.
15.5.2 Massive MIMO and Beamforming
One strategy to improve spectral efficiency is basically to increase the number
antennas and channels. Massive MIMO is an antenna technology that achieves very
high data transfer rates and coverage by using tens (32, 64) and hundreds (128, 256)
of antennas per sector in parallel. Additional antennas create more channels and help
to focus the energy when sending and receiving signals. The transmission power is
reduced in this way and the data rate increases. Also, link reliability improves as
Massive MIMO allows greater degrees of freedom in the selection of uplink and
downlink data streams. This in turn allows extended interference suppression. By
combining and synchronizing the active antennas a focused beams can be created