The developments in technology as well as new trends in social and economic development have led to an increase in the role of communication in day to day life. Mobile phones usage as increased as the cost has reduced and a multitude of applications have been developed. To keep up with these new developments, the International Telecommunication Union (ITU) develops recommendations for the development of mobile communication standards with the aim of reconciling these new and evolving needs with the communication technologies available . The current mobile communication standards were specified in a series of recommendations called IMT 2000 and IMT Advanced. The next phase in mobile communication technology termed as 5G is specified in a new set of recommendations called IMT 2020. 2020 being the year in which the new technology will be released or deployment will start.
This article reviews the vision and objectives for the future development of IMT 2020 and beyond as specified in recommendation M-2083-0. It highlights the key observations in mobile communication trends, reviews the development of IMT, lists the envisaged usage scenarios, and finally lists the capabilities as well as the framework.
Different ways in which communication is used have emerged and the type of applications have evolved. Mobile phones have become data hungrier as software has become liberated by the open source movement that has allowed unprecedented collaboration. The Android operating system is a case in point; leading the charge in the mobile phone operating system space. It has allowed a multitude of applications to be built which has increased the data demand from the networks.
There has been an increase in demand for video streaming services and the use of cloud based services such as music, photos and file storage. These need low latency while maintaining a high quality of service.
Furthermore, we are at the beginning of a new era of connected things termed as the Internet of Things(IoT). The Internet of things will connect all devices that can benefit from connectivity. This will include household appliances such as refrigerators as well as other external appliances such as street lighting, dustbins to mention but a few.
The implication is that a new technology is needed that will address all these somewhat conflicting requirements. There is need to support high traffic, with low latency, high quality, at high mobility in high connectivity geographical areas.
On the technology front, there has been incredible research in the advancement of the radio interface through advanced waveforms, improvement in modulation and coding schemes as well as multiple access schemes. Software defined Networking (SDN) and Network Function Virtualization (NFV) have increased the flexibility of network node deployment and network setup at reduced costs. This has optimized node functions and led to improved operational efficiency.
The radio access resources can be pooled and controlled centrally in what is termed as C-RAN (Cloud RAN) which is a centralised coordination platform for Radio Access Network resources allowing their dynamic allocation with the radio units deployed and managed in a distributed manner. The radio access network (RAN) itself would support advanced self optimization functionality in what is termed as Self Organizing Networks (SON). These have the functionality for inter cell coordination to handle interference mitigation, coverage management , and automatic neighbor relations among other things.
Because of the traffic demands of the IMT 2020 and beyond contiguous and broader bandwidth are needed compared to the currently available IMT systems. A feasibility study was done on frequencies between 6GHz and 100 GHz. The report contains measurement data on propagation in this frequency range in different environments . The report further addresses MIMO based techniques and beam forming with a large number of antennas as well as the feasibility of manufacturing transmitter and receivers operating in frequencies in the mentioned range.
IMT developed from the formation of the International Consultative Committee (CCIR) to address the study question on the future of Public Land Mobile Network Telecommunication Systems (FPLMNS) in 1985. It took 15 years to identify suitable radio spectrum in 1992 and develop recommendations for IMT 2000 which was followed by its deployment. The development involved defining a vision for the framework and the overall objectives for the future development of IMT 2000.
The role of IMT 2020 as a communication system is to continue and improve the contribution of IMT systems to mobile communication through
A wide variety of capabilities and services will be supported as required from the observation in the trends. The usage scenarios are developed from the requirements imposed by the trends. The usage scenarios have been categorized into 3 broad categories with intersecting requirements:
Enhanced mobile broadband addresses uses cases related to user and application usage trends such as an increase in the consumption of multimedia content at high and low degrees of mobility.
The requirement for ultra-reliable and low latency communication addresses the increase in the use of IMT systems in manufacturing, production processes, remote medical surgery, distribution automation , transport safety, etc.
With the advent of the Internet of things, more and more devices are being connected. The devices are required to be of low cost and have a long battery life.
o support the usage scenarios identified, IMT-2020 systems need to support the following capabilities:
The objectives of IMT 2020 are to address the needs of the users as well as incorporating new advances in technology to reduce costs for operators. The capabilities listed are targets for research and investigation and may be revised after more studies are done.
In addition to addressing new usage scenarios, IMT 2020 systems will be able to interoperate with existing IMT systems to allow for smooth transition for operators and gradual adoption by users. It will further support other non IMT access systems
The development plan for IMT 2020 as well as future enhancement to existing IMT systems involves the factors outlined below:
Factors 1-5 will continuously be addressed in the ITU until 2020 when deployment commences. Factor 6, system deployment, will be a gradual process in order to allow the use of existing infrastructure as well as to take into account customer adoption.
The ITU has identified the areas below to be of interest and the focus for research for the new technology.
This article reviews the vision, objectives and framework for IMT-2020 which is the foundation for the next mobile communication standards. It summaries the trends in users and application behaviour, technology advancements, and spectrum implications tied to the needs for the required capabilities.