5G: how technology works and why we need it

5G: how technology works and
why we need it

5G is one of the most talked about technologies at the end of the decade. In August 2019, it reached the peak of inflated expectations according to the Gartner Hype Cycle for Emerging Technologies . As in many similar cases, the information space is full of subjective assessments and fragmentary information. We will try to structure the understanding of 5G in terms of goals, technological parameters and user experience.

What is 5G

This is a new generation of mobile communications with a number of fundamental advantages over 4G:

  • Higher data transfer rate;
  • Low signal latency;
  • The ability to connect more devices;
  • High energy efficiency;
  • Dramatically increased throughput;
  • High user mobility.

Another important difference of 5G deserves attention – large-scale virtualization. New technology goes beyond hardware solutions alone. Many functions in it are implemented not at the level of physical infrastructure, but in software.

The key aspect of the technology, along with the parameters of the network capacity, is the product approach. Frequency bands, design features of stations and software components will be adapted to the needs of various categories of consumers – from users of gadgets to industrial enterprises and urban infrastructure.

5G broadens the context, offering a new understanding of technology: an innovative platform on the basis of which many industries will immediately receive additional impetus for development. This means the emergence of completely new services, business models, types of interactions between devices, production chains and infrastructure.

How the 5G technology appeared

Generations in mobile communications were at first a rather conventional concept, but in retrospect, the chronology of their development looks like this:
1G – ~ 1980. Analog cellular communication.
2G – ~ 1990. The first generation of digital mobile technologies: CDMA, GSM, TDMA. SMS as a killer feature.
3G – ~ 2000. Mobile broadband, several megabits per second: EVDO, HSPA, UMTS;
4G – ~ 2010. Massively available mobile Internet up to gigabit speeds: LTE, WiMAX.In preparation for the deployment of fifth generation networks, we are closest to a single global standard. It is being developed by a number of international organizations, including:


The consortium founded to standardize 3G technology has become one of the industry’s leading organizations, bringing together international regulators and corporate players to jointly develop wireless standards.


The United Nations unit dealing with communications technology. It controls the process of standardization of radio communication technologies, manages the international radio frequency spectrum.
Work on 5G began in 2015, when the ITU-R formulated the IMT-2020 standard containing the key requirements for next-generation technology. In comparison with the previous standard IMT-Advanced, relevant for 4G, they look like this:
Options 4G 5G
Peak download speed 1 Gbps 20 Gbps
Download speed for users 10 Mbps 100 Mbps
Delay 10 ms 4 ms (1 ms for URLLC)
Maximum travel speed without signal loss 350 km / h 500 km / h
Connection density 100 thousand devices / sq. Km 1 million devices / sq. Km
Traffic per unit area 0.1 Mbps / sq.m 10 Mbps / sq.m

ITU-R is the organizer of the World Radiocommunication Conference (WRC or WRC). Every three to four years, the conference discusses key issues in the development of global radio communications and makes strategic decisions.

In 2015, within the framework of WRC-15, a decision was agreed on the allocation of the 3.4-3.6 GHz frequency range for mobile broadband (MBB) – these frequencies will become the basis of 5G for a wide range of users, at least in Europe and the USA. From October 28 to November 22, 2019, WRC-19 is planned, on the agenda of which, in particular, the allocation of bands in the range above 6 GHz.

In turn, 3GPP took over the development of the next generation Radio Access Technology – 5G New Radio or 5G NR. The consortium is working on standards and specifications that will shape the future of technology and the next generation of mobile communications in general. The most relevant of these: the “Release 15” compilation , released in June 2018, containing the initial requirements for 5G, as well as “Release 16” and “Release 17”, which are under development.

Frequency spectrum for 5G

If click bait headlines and enthusiastic posts on social media have convinced you that 5G is about ubiquitous coverage, gigabit speeds, and a frequency range somewhere in the 3-4 GHz region, then you have been misled. The situation is in many ways more prosaic and complex.

First, the transition to the higher frequency range is not directly related to the increase in speed. Second, the spectrum is much broader than the notorious 3.4-3.8 GHz range. 5G will use even such “out of fashion” frequencies as 700 MHz, as well as climb higher – up to 70 GHz.

Finally, at first, don’t expect staggeringly high speeds, especially for casual users. Of course, this is a real prospect, but before the infrastructure in the range of millimeter waves (mmWave) is deployed – the shortest, rapidly decaying, but providing speeds of several gigabits per second – the existing capacities will provide a not so significant increase in parameters.

The main reason for the transition to new bands is the lack of frequencies in the spectrum below 6 GHz. A new generation of mobile communications is being developed to provide operators with free frequencies, and at the same time wider bands within which more data can be transferred.

Formally, there are two ranges within 5G NR:

Frequency Range 1

FR1 includes traditional frequencies, the so-called sub-6 GHz band, that is, below 6 GHz. Some of the bands of previous generations will be transferred to the needs of 5G thanks to frequency refarming. Better coding technologies will allow the new generation of communications to be 30% more efficient than LTE in the same spectrum.

Frequency Range 2

FR2 – fundamentally new frequencies in the millimeter wave range. They start at 24 GHz, going up to ~ 50 GHz and higher depending on the country and operator. These frequencies have a short propagation range and penetrating power. Their operation will be provided not by traditional base stations, but by Small cells – numerous small cells.

FR1 is not homogeneous in different regions of the world. So, in Europe and the USA, it is planned to use the 3.4-3.8 GHz range, and the most serious technology developers are guided by it. On the other hand, the East – Japan and China – are planning to use 4.4-4.99 GHz. Due to the lack of frequencies in the “western” spectrum, Russia plans to use the same range as its Asian neighbors.

Discussions are underway on this score: there are fears that the shortage of compatible equipment will increase the costs of operators and affect the quality of the work of domestic networks. At the same time, the compromise is being considered seriously, and perhaps the necessary frequencies will be allocated.

Frequency refarming

Frequency refarming is not unique to 5G, but it is also remarkable. The fact is that each subsequent generation of mobile communication differs from the previous ones not only by changing the range, but also by new coding technologies. At the same time, it remains possible to work on the basis of the previous generation infrastructure. That is, the stations previously used for LTE or, for example, for GSM, will continue to operate at the same frequencies, but now they will transmit data based on 5G technologies.

Refarming will save on infrastructure by providing optimal coverage for next generation networks. The initial stage of their launch on the existing equipment serving 4G networks is the NSA (Non-standalone) phase. Later, as we prepare the necessary infrastructure, we will be able to use SA (Standalone) 5G networks that support the full range of next-generation benefits.

The width of the line in 5G

The bandwidth determines the amount of data transferred. The wider it is, the more information can be delivered with its help. At the moment, the most common practice is to allocate bands of 5, 10, 20 MHz, combined together up to channels of 100 MHz. When the sub-6 Ghz bands are massively reoriented to 5G, it will be possible to expand the bands up to 160 MHz in them, and in the millimeter wave we will talk about channels of 300, 400 and up to 800 MHz for fixed access.

Who is it for

5G is associated with high-speed internet, AR / VR, smart home, self-driving vehicles. But apart from consumer use, the technology also has an industrial aspect. Moreover, the main customer of the new generation of communications is precisely the corporate sector. The most rapid growth in the volume of transmitted data and the number of devices is shown by the segment of the Internet of things, including industrial.
As the world experience of commercial launch of 5G networks has shown, the number of subscribers with 5G terminals is growing several times faster than it was in 3G and LTE networks. For example, in 3G networks the period when the base reached 500 million users was 10 years. The same number of users in 4G networks has appeared in 5 years. According to analysts, in 5G networks, this threshold will be reached in 3 years.
According to IMT-2020, there are three basic use cases for 5G mobile communications:

eMBB – Enhanced Mobile Broadband / Enhanced Mobile Broadband

A familiar user Internet, but faster and better. Indoor speed can reach 1 Gbps, and outdoors – up to 300 Mbps. Limiting speeds will become possible at the stage of installing the most advanced antennas operating in the millimeter wave (mmWave). They will successfully fit into the landscape due to their small size – for example, on poles, trees, walls of buildings.

URLLC – Ultra Reliable and Low Latency Communications / Ultra reliable communications with low latency

Communications where speed is more important than low latency. This is true for autonomous vehicles, which in a critical situation may take less than a millisecond to make a decision. Currently, there is a discussion about replacing satellite navigation with such technologies.

mMTC – massive Machine Type Communication

Machine-to-machine communications or M2M, as well as IoT are a separate segment of 5G communications consumers. It is characterized by the connection of a large number of devices, most often industrial, with low power consumption, for which the main requirement is stability and reliability of the connection. These are, in particular, measuring devices, sensors, sensors, infrastructure facilities of a smart city.

A specific frequency spectrum and infrastructure is suitable for each of the layers:

  • Radio waves in the low frequency range, up to 1 GHz, due to their penetrating ability, work well in closed rooms. They will ensure the operation of IoT systems, smart houses, M2M. Also, the 700 MHz frequency can use to provide communication for remote settlements.
  • The middle spectrum or mid-band frequencies (1-6 GHz) combines the optimal capacity and coverage for the initial implementation of eMBB, and then URLLC and mMTC.
  • Millimeter waves (> 24 GHz) bring 5G to its full potential. The priority area of ​​application is highly load traffic zones (hot spots), massive user congestion.

Release 16, developed by 3GPP, will add new scenarios to this list, including:

  • V2X (Vehicle-to-Everything) – low latency data transfer between moving unmanned vehicles and cloud data centers for remote management and maintenance.
  • Satellite access – satellite access.

How 5G networks work

Often, next-generation networks will use existing infrastructure inherited from 4G and earlier generations. With more flexible coding and extended data channels, 5G NR will be 25-50% faster than LTE.

At the same time, we are expecting a large-scale implementation of both physical infrastructure and software solutions that will allow us to squeeze the most out of 5G.

Small cells

To deploy standalone networks, new types of stations and transmission devices will install. Since we are talking about shorter wavelengths, which are less resistant to interference and obstructions from the environment, the coverage radius of each base station will be reduced. In this regard, a denser infrastructure will require, consisting of the so-called Small cells – small cells.

As a rule, stations with a capacity of 20-40 watts are use for mobile communication. They will replace by more economical, low-power stations with power ranging from 2 to 10 watts – they will provide massive high-frequency coverage and gigabit speeds.

Small cells fit better into the urban environment; they can  installe on lighting poles, walls of buildings, public transport stops, and can made in the form of a simple object – an advertising lightbox or trash can.

By themselves, millimeter-wave antennas produce a rapidly decaying signal that has a limited directivity – only 4 degrees. But, reflecting off similar antennas along its path, the signal can remain strong and change direction, reaching the user.

Beamforming / Massive MIMO

In radio communication, there is the concept of Beamforming – beamforming. This is the process of directing and concentrating a signal with certain parameters in a certain direction. Within 5G, one of the practical solutions for this will be Massive MIMO (Multiple-In Multiple-Out) technology. It will help to avoid excessive microcell installation all over the place.

Massive MIMO refers to stations consisting of a large array of antennas that will be able to direct the signal more targeted and serve multiple users simultaneously, avoiding interference and loss of signal quality.

It is clear today that 5G adoption is an evolutionary process. At least until 2022, we see an economically justified launch of 5G fragments based on the LTE network using a non-standalone architecture – Non-Standalone – from LTE-A to LTE-Evo and further to 5G NR. This will happen due to the introduction of certain 5G technologies, such as Massive MIMO, Cloud Air, Short TTI.

One of the key breakthroughs in next-generation networks is virtualization . With concepts such as SDN (Software Defined Networks) and NFV (Network Function Virtualization), entire classes of functions will be implemented in software rather than physical hardware.

An equally important role is played by the cloud architecture – C-RAN (Cloud / Centralized RAN). Cloud platforms will take over the functions that were previously performed by base station equipment, which will greatly optimize the infrastructure and affect the costs of operators.

The cloud platform requires less energy for maintenance and cooling than base stations. C-RAN knows the location of all users and can optimally allocate limited network resources between them.

Japanese operator NTT DOCOMO uses cloud infrastructure to cut power consumption of stations by more than 75% .

Technology implementation risks

Like any new technology, 5G carries risks. Whether they are justified or not is difficult to say – in most cases we are dealing with a research stage.

The main threats can consider:


The Internet of Things is susceptible to attacks just like any electronic device. Users will have to take care of the security of their devices, and companies and governments will have to make serious efforts to ensure the protection of smart cities and IIoT.

Frequency crossing

Many frequency spectra are still operate by special services and institutions. Allocation of ranges for commercial use will require careful and comprehensive agreement.

what 5G Damage to health

In July 2019, a number of Russian departments announced that they intend to analyze the impact of 5G networks on public health . The Ministry of Health, the Ministry of Telecom and Mass Communications, Rospotrebnadzor, the Federal Medical and Biological Agency (FMBA) and the Moscow Department of Information Technologies (DIT) will conduct research and formulate current standards.
Market situation
  • According to Gartner , revenues from 5G wireless networks will grow 89% in 2020 from 2019 to $ 4.2 billion.
  • In Russia, operators’ investments in the development of 5G networks for the period 2020-2027 are estimate at 550-610 billion rubles, and with the joint use of base stations – at 400-445 billion.
  • Mobile operators around the world are announcing 5G test launches . Devices on which the tests were successful: LG V50, OnePlus 7 Pro 5G, Samsung Galaxy S10 5G, Moto Z2 Force / Z3 / Z4.
  • In Russia, VimpelCom report that the radio part of the network in Moscow was 95% ready. Tele2 is installing 50 thousand 5G-ready base stations.
Regarding Russian realities, the opinions of representatives of mobile operators coincide. Uncertainty in the issue of frequencies does not allow us to give clear recommendations to consumers.