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• URLLC (Ultra Reliable Low-Latency Communications). URLLC is targeted towards applications
that are highly latency-sensitive, such as factory automation and autonomous driving. URLLC is
targeting latencies of1msec.

As of this writing, technologies that enable URLLC are still being standardized.
• mMTC (Massive Machine Type Communications). mMTC is a narrowband access type for
sensing, metering, and monitoring applications. One priority for the design of 5G networks is to
lower barriers for network connectivity for IoT devices. In addition to lowering latency, emerging
technologies for 5G networks are focusing on reducing power requirements, making the use of
IoT devices more pervasive than has been with 4G LTE. 5G and Millimeter Wave Frequencies
Many 5G innovations will be a direct result of working in the millimeter wave frequencies in the
24 GHz–52 GHz band. For example, these frequencies offer the potential of achieving 100x
increase in capacity over 4G.

To get some insight into this, capacity can be defined as the product of three terms [Björnson
2017]: capacity = cell density
* available spectrum

* spectral efficiency where cell density is in units of cells/km2, available spectrum is in units of
Hertz, and spectral efficiency is a measure of how efficiently each base station can communicate
with users and is in units of bps/Hz/cell.

By multiplying these units out, it is easy to see that capacity is in units of bps/km2. For each of
these three terms, the values will be larger for 5G than for 4G:
• Because millimeter frequencies have much shorter range than 4G LTE frequencies, more base
stations are required, which in turn increases the cell density.

• Because 5G FR2 operates in a much larger frequency band (52 24 than 4G LTE (up to about 2
GHz), it has more available spectrum. 28 GHz)

• With regard to spectral efficiency, information theory says that if you want to double spectral
efficiency, a 17-fold increase in power is needed [Björnson 2017].
Instead of increasing power, 5G uses MIMO-technology, which uses multiple antennas at each
base station. Rather than broadcasting signals in all directions, each MIMO antenna employs
beam forming and directs the signal at the user.
MIMO technology allows a base station to send to 10–20 users at the same time in the same
frequency band. By increasing all three terms in the capacity equation, 5G is expected to provide
a 100x increase in capacity in urban areas. Similarly, owing to the much wider frequency band,
5G is expected to provide peak download rates of 1 Gbps or higher.
Millimeter wave signals are, however, easily blocked by buildings and trees. Small cell stations
are needed to fill in coverage gaps between base stations and users. In a highly populous region,
the distance between two small cells could vary from 10 to 100 meters [Dahlman 2018]. 5G Core
Network The 5G Core network is the data network that manages all of the 5G mobile voice, data
and Internet connections.

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