We can all agree 5G is the next big thing in cellular
comms. It’s also fair to say it promises to radically
impact digital connectivity on a much broader basis.
So, let’s kick off by investigating 5G’s technical
characteristics and how, ultimately, it works.
At the highest level you can divide 5G into
two main elements, both of which are critical to
delivering its benefits. Most obvious is the Radio
Access Network. That’s the collection of wireless
access points to which client devices connect: small
local cells, larger towers and masts, and dedicated
in-building and home access points that connect
users and wireless devices to the core network.
It’s that core network that forms the other half
of the equation. It combines the mobile exchange
and data network that supports the network’s
functionality of voice, data, and Internet connectivity.
For 5G, this core network is designed to hook in
seamlessly with the Internet and cloud-based
services, and include infrastructure and software
expressly intended to not just increase bandwidth,
but also reduce latency and lag.
The initial frequency bands for 5G will be around
600–700MHz, 3–4GHz, 26–28GHz, and 38–42GHz.
In basic terms, that will add much more capacity
compared to current mobile technologies, enabling
more users, more data, and faster connections.
One significant new feature on 5G networks from
a wireless access perspective involves a new class
of small millimeter wave (mmWave) cells designed
for short-range connections of roughly 10 to a few
hundred yards. These local cells are designed to be
positioned in clusters where there are high numbers
of users, and complement the macro network that
delivers the wide-area coverage. One of the earliest
movers in 5G in the US, Verizon, has built some of
these smaller nodes into street lighting in Chicago.
Larger 5G macro cells, meanwhile, use what’s
known as MIMO (multiple input, multiple output)
antennas that have an array of elements to support
more users and bandwidth. MIMO antennas are
sometimes spoken of as “Massive MIMO,” thanks
to the really large number of antenna elements, but©^PIXABAY.^ G
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GLE.their actual physical size is comparable to existing
3G and 4G base station antennas.
Operators in the US will initially integrate 5G with
existing 4G networks. The 5G radio system, known
as 5G-NR, isn’t compatible with 4G technology, but
all early 5G devices in the US will use 4G for initial
connections and control signaling, before hooking
up to 5G for fast data where available. In terms of
time to roll out, expect reasonably widespread 5G
availability in 2022, and what you might call truly
blanket 5G coverage by 2025 or thereabouts.CLOSE TO THE EDGE
If wireless connectivity via the Radio Access
Network is the most visible aspect of 5G, it’s the
upgrades it brings to the core network that will be
critical for improving latency. Central to that is the
idea of “edge” computing, which is all about bringing
computing closer to the end user. In other words,
instead of relying on huge public cloud computing
infrastructure, located centrally and at distance
from end users, the idea is to install “cloudlet”
servers and other computing resources much more
locally, to move the application or content close to
the radio at the “edge” of the network.
It’s a radical change. It can mean installing
servers in 5G base stations to host content and
run applications much closer to end users. For
consumers, the impact would be felt in areas such
as near-instant response when firing up video
streams, or reduced lag in streamed games. But it’s
in enabling whole new usage cases that 5G’s edge
computing approach will have its biggest impact.
Which brings us to the broader subject of what 5G
is for. The whole 4K-Netflix-up-a-mountain thing
gets the basic idea of speed across, and represents
one of the three main prongs of 5G, that of enhanced
mobile broadband, but there’s so much more
to 5G. Next up is massive machine-to-machine
connectivity, and support for an unprecedented
number of devices. Whether it’s sensors or IoT
(Internet of Things) devices, the implication is
billions of devices connected and communicating
without immediate human intervention.
The third and final major usage model involves
applications where low latency is critical. That
means real-time control of devices, industrial
robotics, car-to-car comms and autonomousGame streaming services
like Google’s Stadia will
benefit from 5G’s low-
latency “edge” computing.5G is a key technology in
enabling an autonomous
future for cars, and
solving both safety
and traffic problems.the 5G dream
46 MAXIMUMPC SEP 2019 maximumpc.com