In telecommunications, 5G is
the fifth-generation technology
standard for broadband cellular networks, which cellular phone
companies began deploying
worldwide in 2019, and is the planned successor to the 4G networks which
provide connectivity to most current cellphones. 5G networks are predicted to have more than 1.7 billion
subscribers and account for 25% of the worldwide mobile technology market by
2025, according to the GSM Association and Statista.
Like its predecessors, 5G
networks are cellular networks, in which the service area is divided into
small geographical areas called cells. All 5G wireless devices in a
cell are connected to the Internet and telephone network by radio waves through a local antenna in the cell. The new networks have higher download speeds, eventually up to 10 gigabits per
second (Gbit/s). In
addition to 5G being faster than existing networks, 5G has higher bandwidth and
can thus connect more different devices, improving the quality of Internet
services in crowded areas. Due to the increased bandwidth, it is expected
the networks will increasingly be used as general internet
service providers (ISPs)
for laptops and desktop computers, competing with existing ISPs such as cable internet, and also will make possible new applications
in internet-of-things (IoT), Telematics and machine-to-machine areas. Cellphones with 4G capability
alone are not able to use the 5G networks. 5G networks is
expected to support up to a million devices per square kilometer.
The industry consortium setting standards for 5G, the 3rd
Generation Partnership Project (3GPP), defines "5G"
as any system using 5G NR (5G
New Radio) software, and the specification is
subdivided into two frequency bands, FR1 (below 6 GHz) and FR2
(24–54 GHz).
5G can be implemented in
low-band, mid-band, or high-band millimeter-wave 24 GHz up to 54 GHz.
Low-band 5G uses a similar frequency range to 4G cellphones, 600–900 MHz, giving download speeds a little higher than 4G: 30–250 megabits per
second (Mbit/s). Low-band cell towers have a range and coverage area similar to 4G towers.
Mid-band 5G uses microwaves of 1.7–4.7 GHz, allowing speeds of 100–900 Mbit/s, with each cell tower providing
service up to several kilometers in radius. This level of service is the most
widely deployed and was deployed in many metropolitan areas in 2020. Some
regions are not implementing the low band, making Mid-band the minimum service
level. High-band 5G uses frequencies of 24–47 GHz, near the bottom of the
millimeter wave band, although higher frequencies may be used in the future. It
often achieves download speeds in the gigabit-per-second (Gbit/s) range, comparable to cable
internet. However, millimeter waves (mmWave or mmW) have a more limited
range, requiring many small cells. Small cells are low-powered cellular
radio access nodes that operate in licensed and unlicensed spectrums that have a
range of 10 meters to a few kilometers. Small cells are critical to 5G
networks, as 5G's radio waves can't travel long distances, because of 5G's
higher frequencies, 5G signals cannot penetrate solid objects easily, such as
cars, trees, walls, and even humans, because of the nature of these higher
frequency electromagnetic waves. Due to their higher cost, plans are to
deploy these cells only in dense urban environments and areas where crowds of
people congregate such as sports stadiums and convention centers. In
applications area, 5G technology will connect some of the 50 billion connected
IoT devices. Most will use the less expensive Wi-Fi. Drones, transmitting
via 4G or 5G, will aid in disaster recovery efforts, providing real-time data
for emergency responders. Most cars will have a 4G or 5G cellular
connection for many services. Autonomous cars do not require 5G, as they have
to be able to operate where they do not have a network
connection. However, most autonomous vehicles also feature teleoperations
for mission accomplishment, and these greatly benefit from 5G technology.
Beyond mobile operator
networks, 5G is also expected to be used for private networks with applications
in industrial IoT, enterprise networking, and critical communications, in what
being described as NR-U (5G NR in Unlicensed Spectrum).
Radio waves receptions and health
effects
Radio waves are a type of electromagnetic
radiation with the
longest wavelengths in the electromagnetic
spectrum, typically with frequencies of 300 gigahertz (GHz) and below. At
300 GHz, the corresponding wavelength is 1 mm (shorter than a grain of rice); at
30 Hz the corresponding wavelength is 10,000 kilometers (6,200 miles)
(longer than the radius of the Earth). Like all electromagnetic waves, radio
waves in a vacuum travel at the speed of light, and in the Earth's atmosphere at a close, but
slightly lower speed.
Radio waves are generated
artificially by an electronic device called a transmitter, which is connected to an antenna which radiates the waves. They are received by another antenna
connected to a radio receiver, which processes the received signal. Radio
waves are very widely used in modern technology for fixed and mobile radio
communication, broadcasting, radar and radio navigation systems, communications
satellites, wireless computer networks and many other applications. Different
frequencies of radio waves have different propagation characteristics in the
Earth's atmosphere; long waves can diffract around obstacles like mountains and follow the contour of the
earth (ground waves), shorter waves can reflect off the ionosphere and return to earth beyond the horizon (skywaves), while much shorter wavelengths bend or diffract very little and
travel on a line of
sight, so their propagation
distances are limited to the visual horizon.
Radio waves are non-ionizing
radiation, which means they do not have enough energy to
separate electrons from atoms or molecules, ionizing them, or break chemical bonds, causing chemical reactions or DNA damage. The main effect of absorption of radio waves by materials
is to heat them, similarly to the infrared waves radiated by sources of heat such as a space heater or wood fire. The oscillating electric field of the
wave causes polar
molecules to vibrate back and
forth, increasing the temperature; this is how a microwave oven cooks food. However, unlike infrared
waves, which are mainly absorbed at the surface of objects and cause surface
heating, radio waves are able to penetrate the surface and deposit their energy
inside materials and biological tissues. The depth to which radio waves
penetrate decreases with their frequency, and also depends on the material's resistivity and permittivity; it is given by a parameter called the skin depth of the material, which is
the depth within which 63% of the energy is deposited. For example, the
2.45 GHz radio waves (microwaves) in a microwave oven penetrate most foods
approximately 2.5 to 3.8 cm (1 to 1.5 inches). Radio waves have been
applied to the body for 100 years in the medical therapy of diathermy for deep heating of body tissue, to promote increased
blood flow and healing. More recently they have been used to create higher
temperatures in hyperthermia treatment and to kill cancer cells.
Looking into a source of radio waves at close range, such as the waveguide of a working radio transmitter, can cause damage to the
lens of the eye by heating. A strong enough beam of radio waves can penetrate
the eye and heat the lens enough to cause cataracts.
Since the heating effect
is in principle no different from other sources of heat, most research into
possible health hazards of exposure to radio waves has focused on "nonthermal"
effects; whether radio waves have any effect on tissues besides that caused by
heating. Radiofrequency electromagnetic fields have been classified by
the International Agency for Research on Cancer (IARC) as having "limited
evidence" for its effects on humans and animals. There is weak mechanistic
evidence of cancer risk via personal exposure to RF-EMF from mobile telephones. The FDA is quoted as saying that it "...continues to
believe that the current safety limits for cellphone radiofrequency energy
exposure remain acceptable for protecting the public health."
Installing new
5G base stations over a given area may result in an uncontrollable increase of
radiofrequency "pollution": Dense deployment of 5G base stations is beneficial to the users
living in proximity to them, because there is abrupt decrease of radiofrequency
compared to sparse deployment. Installing additional base stations over
the area may be needed for supporting an increasing number of users with higher
data rates. As a result, the distance between users and the nearest base
station shrinks. This is called network densification, which may be wrongly
perceived to increase the health impacts of 5G. However, unlike the common
perception, network densification can reduce the average electromagnetic field
exposure. Lower network densification means that each base station should cover
a larger area, leading to higher radiated power for each
cell. Additionally, dense deployment of 5G base stations leads to reduced
radiation from mobile phones since connecting base stations are closer to
mobile phones. Typically, radiation from base stations is lower than the
radiations from mobile phones, since the radiation power decreases with the
square of distance from the source.
5G Networks are wide open and connected to
serve more versatile applications
The Internet of things (IoT) describes
physical objects (or groups of such objects) with sensors, processing ability, software and other technologies that connect and
exchange data with other devices and systems over the Internet or other communications
networks. Internet of things has been considered a misnomer because devices do not need to be connected
to the public internet, they only need to be connected to a network and be
individually addressable.
The field has evolved due to the convergence of multiple technologies, including ubiquitous computing, commodity sensors, increasingly powerful embedded systems, as well as machine learning. Traditional fields of embedded systems, wireless sensor networks,
control systems, automation (including home and building automation),
independently and collectively enable the Internet of things. In the
consumer market, IoT technology is most synonymous with
products pertaining to the concept of the "smart home",
including devices and appliances (such as lighting fixtures, thermostats, home security systems, cameras, and other home appliances)
that support one or more common ecosystems, and can be controlled via devices
associated with that ecosystem, such as smartphones and smart speakers. IoT is also used in healthcare systems
Telematics is an
interdisciplinary field encompassing telecommunications, vehicular technologies (road transport, road safety, etc.), electrical engineering (sensors,
instrumentation, wireless
communications, etc.),
and computer
science (multimedia, Internet, etc.). Telematics can involve any of the following:
·
The technology of sending, receiving, and storing information
using telecommunication devices to control remote objects
·
The integrated use of telecommunications and informatics for application in vehicles
and to control vehicles on the move
·
Global navigation satellite
system technology integrated with computers and mobile communications technology
in automotive
navigation systems
·
(Most narrowly) The use of such systems within road vehicles (also called vehicle
telematics)
Machine to machine (M2M) is direct
communication between devices using any communications channel,
including wired and wireless. Machine to machine communication can
include industrial instrumentation, enabling a sensor or meter to communicate
the information it records (such as temperature, inventory level, etc.) to
application software that
can use it (for example, adjusting an industrial process based on temperature
or placing orders to replenish inventory). Such communication was
originally accomplished by having a remote network of machines relay
information back to a central hub for analysis, which would then be rerouted
into a system like a personal computer.