With the 4G telecommunications systems now starting to be deployed, eyes are looking towards the development of 5th generation or 5G technology and services.
Although the deployment of any wireless or cellular system takes many years, development of the 5G technology systems is being investigated. The new 5G technologies will need to be chosen developed and perfected to enable timely and reliable deployment.
The new 5th generation, 5G technology for cellular systems will probably start to come to fruition around 2020 with deployment following on afterwards.
5G mobile systems status
The current status of the 5G technology for cellular systems is very much in the early development stages. Very many companies are looking into the technologies that could be used to become part of the system. In addition to this a number of universities have set up 5G research units focussed on developing the technologies for 5G
In addition to this the standards bodies, particularly 3GPP are aware of the development but are not actively planning the 5G systems yet.
Many of the technologies to be used for 5G will start to appear in the systems used for 4G and then as the new 5G cellular system starts to formulate in a more concrete manner, they will be incorporated into the new 5G cellular system.
The major issue with 5G technology is that there is such an enormously wide variation in the requirements: superfast downloads to small data requirements for IoT than any one system will not be able to meet these needs. Accordingly a layer approach is likely to be adopted. As one commentator stated: 5G is not just a mobile technology. It is ubiquitous access to high & low data rate services.
5G cellular systems overview
As the different generations of cellular telecommunications have evolved, each one has brought its own improvements. The same will be true of 5G technology.
First generation, 1G: These phones were analogue and were the first mobile or cellular phones to be used. Although revolutionary in their time they offered very low levels of spectrum efficiency and security.
Second generation, 2G: These were based around digital technology and offered much better spectrum efficiency, security and new features such as text messages and low data rate communications.
Third generation, 3G: The aim of this technology was to provide high speed data. The original technology was enhanced to allow data up to 14 Mbps and more.
Fourth generation, 4G: This was an all-IP based technology capable of providing data rates up to 1 Gbps.
Any new 5th generation, 5G cellular technology needs to provide significant gains over previous systems to provide an adequate business case for mobile operators to invest in any new system.
Facilities that might be seen with 5G technology include far better levels of connectivity and coverage. The term World Wide Wireless Web, or WWWW is being coined for this.
For 5G technology to be able to achieve this, new methods of connecting will be required as one of the main drawbacks with previous generations is lack of coverage, dropped calls and low performance at cell edges. 5G technology will need to address this.
Although the standards bodies have not yet defined the parameters needed to meet a 5G performance level yet, other organisations have set their own aims, that may eventually influence the final specifications.
Typical parameters for a 5G standard may include:
|SUGGESTED 5G WIRELESS PERFORMANCE
||10 000 times current network
|Peak data rate
|Cell edge data rate
||< 1 ms
These are some of the ideas being put forwards for a 5G standard, but they are not accepted by any official bodies yet.
There are several key areas that are being investigated by research organisations. These include:
- Millimetre-Wave technologies: Using frequencies much higher in the frequency spectrum opens up more spectrum and also provides the possibility of having much wide channel bandwidth – possibly 1 – 2 GHz. However this poses new challenges for handset development where maximum frequencies of around 2 GHz and bandwidths of 10 – 20 MHz are currently in use. For 5G, frequencies of above 50GHz are being considered and this will present some real challenges in terms of the circuit design, the technology, and also the way the system is used as these frequencies do not travel as far and are absorbed almost completely by obstacles.
- Future PHY / MAC: This area presents many possibilities from the use of new modulation formats including GFDM, Generalised Frequency Division Multiplexing, as well as FBMC, Filter Bank Multi-Carrier, UFMC, Universal Filtered MultiCarrier and other schemes to the management of the multiple access schemes. All these need to be developed. Higher levels of processing that will be available by the time 5G is launched mean that multicarrier systems will not require to be orthogonal as in the case of OFDM. This provides considerably more flexibility.
- Massive MIMO: Although MIMO is being used in many applications from LTE to Wi-Fi, etc, the numbers of antennas is fairly limited -. Using microwave frequencies opens up the possibility of using many tens of antennas on a single equipment becomes a real possibility because of the antenna sizes and spacings in terms of a wavelength.
- Dense networks Reducing the size of cells provides a much more overall effective use of the available spectrum. Techniques to ensure that small cells in the macro-network and deployed as femtocells can operate satisfactorily are required.
Other 5G concepts
There are many new concepts that are being investigated and developed for the new 5th generation mobile system. Some of these include:
- Pervasive networks : This technology being considered for 5G cellular systems is where a user can concurrently be connected to several wireless access technologies and seamlessly move between them.
- Group cooperative relay: This is a technique that is being considered to make the high data rates available over a wider area of the cell. Currently data rates fall towards the cell edge where interference levels are higher and signal levels lower.
- Cognitive radio technology: If cognitive radio technology was used for 5th generation, 5G cellular systems, then it would enable the user equipment / handset to look at the radio landscape in which it is located and choose the optimum radio access network, modulation scheme and other parameters to configure itself to gain the best connection and optimum performance.
- Wireless mesh networking and dynamic ad-hoc networking: With the variety of different access schemes it will be possible to link to others nearby to provide ad-hoc wireless networks for much speedier data flows.
- Smart antennas: Another major element of any 5G cellular system will be that of smart antennas. Using these it will be possible to alter the beam direction to enable more direct communications and limit interference and increase overall cell capacity.
There are many new techniques and technologies that will be used in the new 5G cellular or mobile telecommunications system. These new 5G technologies are still being developed and the overall standards have not yet be defined. However as the required technologies develop, they will be incorporated into the new system which will be defined by the standards bodies over the coming years.
No formal dates have been set yet for the development of 5G, but a number of companies and organisations have set their own 5G timelines so they can plan ahead.
There are many elements to the overall 5G timeline – everything from the investigation and development of new technologies, to the standardisation process, and the release of spectrum needed to support 5G.
Accordingly the various elements in the 5G timeline need to be closely managed and all the elements brought together to enable the system to be launched in the required timescale.
One major enabler for 5G will be the release of frequency spectrum and this needs to be managed on a global scale to ensure commonality and also the reduction of interference between services, especially those operating globally. This process is managed under the auspices of the International Telecommunications Union, ITU.
To manage the process of spectrum allocations, large international meetings called the World Radio Conference, WRC are held every four years. There is one in 2015, another in 2019, and this is followed four years later by one in 2023..
A summary of the WRC dates and timeline is:
- 2015 – WRC15: In this World Radio Conference, the main focus for mobile telecommunications is for providing additional frequency spectrum for 4G services. Work is not yet sufficiently advanced for determining allocations for 5G.
- 2019 – WRC19: By this date, it is anticipated that work on 5G will have advanced sufficiently, and this will have allowed adequate work to be undertaken to determine the spectrum requirements for 5G. More will be required at frequencies below 5GHz, but additional spectrum is anticipated for frequencies above 5GHz as well. It is within this timeframe that 5G allocations will be discussed.Although the earliest deployments for 5G may occur around 2020, these will be comparatively limited and its use not as wide as it is anticipated to be later. Accordingly the dates for spectrum release for 5G will progressively occur as 5G deployments increase and the bandwidth requirements grow.
- 2023 – WRC23 : Work towards WRC23 will only commence properly once WRC19 has taken place. However many will be looking towards this timeframe for further allocations for 5G and beyond.
Technology investigation timescales
One of the key elements in the early stages of 5G is the development of the basic technology. This started shortly after the first deployments of 4G.
Although the timeline for the research phase can only be broadly bounded and work will be ongoing even after the system enters service, it is anticipated that the basic research and investigations will need to be complete by around 2016 to enable this to feed into the standardisation process.
Standardisation process timelines
Standardisation is a key element of the 5G process. The timescales and dates of this activity are key to the successful deployment of 5G. It also involves several agencies including 3GPP, ETSI, NGMN, IEEE, and the like.
Possibly one of the key authorities is 3GPP. Their standards are used for the definition of the cellular standard, but with 5G being an aggregation of technologies, it is likely to require a number of standards institutions to work together.
The submission for the IMT 2020 are to follow the following dates and deadlines:
- Initial technology submission date:
- Detailed specification submission date
One of the key elements of the 5G developments themselves is the work on the radio access network, RAN. It is anticipated that the discussions on the RAN could be started around December 2015.
It is anticipated that the bulk of the requirements will be agreed in the first 6 months of the RAN discussion to guide the work in the working groups.
5G useful life timescale
It is generally estimated that the timescale for the first 5G networks will be around 2020, although there is pressure for some operators to launch much earlier.
However the useful lifetime for 5G is likely to be long. As it is aimed at providing general connectivity, and for IoT and M2M communications many of these applications will need to remain in place for many years. Utility meters, for example remain in place for many years, and the utility companies will not take kindly to having to replace their meters more frequently to follow the cellular technologies. Accordingly the useful life timescale for 5G is anticipated to remain in use until at least 2040.