This past week has seen a wide range of activities in the technology space with the key highlight in Kenya being the launch of the Lipa Mdogo Mdogo programme by Safaricom in partnership with Google. The name of the programme in Swahili loosely translates to pay slowly. The programme will avail one million 4G enabled smartphones to Kenyans through a down-payment of 1,000 Shillings and daily payments of 20 shillings for up to nine months. The Communications Authority of Kenya reports that there are over 22.3 million broadband subscriptions in Kenya and mobile broadband subscriptions accounted for 97.6 percent of the total broadband subscriptions. The increase in 4G adoption in Kenya is bound to have a tremendous impact on various facets of life for Kenyans who have previously been unable to afford 4G devices.
As Kenyans begin to harness the gains of interconnectivity through 4G it appears that geopolitics will shape the adoption of the next generation connectivity technology which is 5G. The US Department of Commerce’s Bureau of Industry and Security (BIS) in May 2019 placed Huawei and a number of its affiliates on the Entity List with the main reason being that Huawei’s activities are contrary to U.S. national security or foreign policy interests. Further in May 2020 the Department of Commerce banned semiconductor chip makers in South Korea and Taiwan from using U.S machines and software to manufacture semiconductor chips needed for the building of 5G infrastructure. China on the other hand has threatened to take forceful countermeasures to protect its own legitimate rights. The UK in mid-July banned its mobile providers from buying new Huawei 5G equipment after 31st December 2020 and must remove all Huawei 5G equipment from their networks by 2027. China has threatened to retaliate against the Chinese operations of Nokia and Ericsson if EU members take a similar position as that of the US and the UK.
Despite the geopolitical challenges regulators are moving forward with building an enabling environment for the adoption of 5G. The World Radio Communication Conference in 2019 (WRC-19) approved additional Spectrum for International Mobile Telecommunications (IMT)-2020 (5G mobile) to facilitate implementation of 5G mobile services worldwide.
Despite the head-wings surrounding the 5G race Samsung has laid out its 6G vision. Samsung expects that 6G will provide ultimate experience for all through hyper-connectivity involving humans and everything. We have gleaned a few insights from Samsung’s 6G vision and these are highlighted below.
The four major megatrends advancing toward 6G are:-
● connected machines
● use of AI for the wireless communication
● openness of mobile communications
● increased contribution for achieving social goals.
It is expected that the number of connected devices will reach 500 billion by 2030, which is about 59 times larger than the expected world population (8.5 billion) by that time. Mobile devices will take various form-factors, such as augmented reality (AR) glasses, virtual reality (VR) headsets, and hologram devices. Increasingly, machines will need to be connected by means of wireless communications.
As the number of connected machines grows, the machines will become dominant users of 6G communications. A look at the history of wireless communications shows that technologies have been developed while assuming services for humans as the major driving applications. In 5G, machines were also considered in defining requirements and developing technologies. We expect new 6G technologies to be developed specifically to connect hundreds of billions of machines taking into account what is required for machines.
Use of AI for the wireless communication
The application of AI in wireless communications holds the potential to improve performance and reduce capital expenditure (CAPEX) and operational expenditure (OPEX). But there is a limit to what is achievable today, as use of AI in communication networks was not considered when developing existing communication systems such as 5G. In the case of 6G, knowing that AI technologies are available for practical applications, systems can be developed that take into account the possibility of embedding AI in various entities comprising wireless networks and services. A tremendous amount of data associated with hundreds of billions of connected machines and humans needs to be collected and utilized in 6G systems.
Considering AI from the initial phase of developing concepts and technologies for 6G will give us more opportunities to take advantage of AI for improvement of overall network operation in terms of performance, cost, and ability to provide various services.
Openness of mobile communications
Substantial improvements of the computing power of general purpose processors such as central processing units (CPUs) and graphic processing units (GPUs) enabled software-based implementations of network entities including core networks and BSs. This trend also makes open source software an attractive option to realize network functions, as it can lower barriers to market entry, promote interoperability, and expedite development cycles based on shared knowledge.
Increased contribution for achieving social goals.
There will be a societal need for 6G mobile communications, to contribute even more to address social issues and achieve the SDGs. Hyper-connectivity and ultimate experience delivered by 6G mobile communications will improve and enable access to required information, resources (both virtual and physical), and social services without constraints of time and physical location. A wide deployment of 6G will reduce differences in regional and social infrastructure and economic opportunities and thereby provide alternatives to rural exodus, mass urbanization and its attendant problems. We expect that 6G mobile communications will play an important role in the achievement of the UN’s SDGs, and tremendously contribute to the quality and opportunities of human life.
Major services that have to be taken into account in developing 6G technologies.
New 6G services will emerge due to advances in communications as well as other technologies such as sensing, imaging, displaying, and AI. Those new services will be introduced through hyper-connectivity involving humans and everything and provide ultimate multimedia experience. The three key 6G services are, namely, truly immersive extended reality (XR), high-fidelity mobile hologram, and digital replica.
Truly Immersive XR
XR is a new term that combines VR, AR, and mixed reality (MR). It has attracted great attention and opened new horizons in various fields including entertainment, medicine, science, education, and manufacturing industries. Technical development to realize XR is still in progress, and new innovative technologies are constantly appearing. The critical obstacle between the potential and reality of XR is hardware. In particular, these technologies require advanced device form-factors, such as hand-held components, to support mobile and active software content. Current mobile devices lack sufficient stand-alone computing capability. Unfortunately, progress in hardware performance, especially mobile computing power and battery capacity, cannot keep pace with what the boom of XR requires.
This discrepancy could severely deter market expansion. In our view, these challenges can be overcome by offloading computing to more powerful devices or servers. Another challenge is sufficient wireless capacity. Note that current AR technology requires 55.3 megabits per second (Mbps) to support 8K display (with one million points), which can provide enough user experience on a mobile display.
The current user experienced data rate of 5G is not sufficient forseamless streaming. It is expected that the market sizes for VR and AR will reach $44.7 billion and $87 billion, respectively, by 2030.
High-Fidelity Mobile Hologram
Hologram is a next-generation media technology that can present gestures and facial expressions by means of a holographic display. The content to display can be obtained by means of real-time capture, transmission, and 3D rendering techniques. In order to provide hologram display as a part of real-time services, extremely high data rate transmission, hundreds of times greater than current 5G system, will be essential.
A hologram display over a mobile device form-factor requires at least 0.58 Tbps. The peak data rate of 5G is 20 Gbps. 5G cannot possibly support such an extremely large volume of data as required for hologram media in real-time. To reduce the magnitude of data communication required for hologram displays and realize it in the 6G era, AI can be leveraged to achieve efficient compression, extraction, and rendering of the hologram data. The market size for the hologram displays is expected to be $7.6 billion by 2023.
With the help of AI and ICT, it will be possible to replicate physical entities, including people, devices, objects, systems, and even places, in a virtual world. This digital replica of a physical entity is called a digital twin. With 6G, users will be able to explore and monitor the reality in a virtual world, without temporal or spatial constraints through digital twins.
Users will be able to observe changes or detect problems remotely through the representation offered by digital twins. Users will be even able to go beyond observation, and actually interact
with the digital twins, using VR devices or holographic displays.
With the help of AI, digital replication, management of real world and problem detection and mitigation can be done efficiently without the presence or even detailed supervision by a human being. For instance, if a problem is detected in the digital twin representation, AI can invoke required actions in the real world.
Requirements to realize the expected services for 6G:
Relying only on improvement of the communication link performance does not suffice to realize new 6G services. This is because the progress of increase in mobile computing power is not keeping pace with the growth rate of the computing power requirements.
The limitation on computing power and battery life of mobile devices highlights the need for taking a holistic view on the overall architecture of 6G systems including network entities as well as mobile devices. In addition, the openness of mobile communications as a new megatrend toward 6G gives rise to the need for defining new requirements to maintain security and keep the trust of subscribers.
They consist of :
● performance requirements,
● architectural requirements; and
● trustworthiness requirements.
6G needs to provide a much higher data rate than 5G. While 5G was designed to achieve 20 Gbps peak data rate, for 6G the peak data rate should be 1,000 Gbps and a user experienced data rate of 1 Gbps.
In the 6G era, users will expect seamless high-end services in their everyday lives, ideally with improved battery life. Considering the growing concern about environmental sustainability, the energy consumption of 6G networks should be minimized. The energy efficiency of both devices and networks should improve by at least two times.
The architecture of 6G communication network should be developed so that it can resolve the issues arising from the limited computation capability of mobile devices. A possible way to achieve this is to offload computation tasks to more powerful devices or servers. In order to support offloading of real-time intensive computation tasks, hyper-fast data rate and extremely low latency communications are required. Understanding that there must be practical limits on the achievable data rate and latency, the communication network should be designed in a holistic manner, so as to best utilize computation power that can be made available by various entities in the network. We term this joint design “communications and computing convergence.”
On top of the communications and computing convergence, AI will need to be embedded in all system components in 6G networks. We call this design approach “native AI,” which allows all system components to obtain and evaluate a massive amount of real-time information. In this way, systems can handle complex optimization tasks across layers to optimize the system parameters and overall system performance. The 6G network should be designed to support terrestrial components, trustworthiness requirements.
The use of open source
The use of open source software and personal user information will increase the openness of
communication systems and hence increase the attack surface. This could make the whole system more vulnerable to security and privacy threats.
Considering the increasing risk of security threats, we expect that trustworthiness will become an essential requirement.
Candidate technologies that will be essential to satisfy the requirements for 6G, currently include:
● support of the terahertz band,
● novel an-tenna technologies,
● evolution of duplex technology,
● evolution of network topology,
● spectrum sharing,
● comprehensive AI,
● split computing, and
● high-precision network.
Support of the terahertz band
In March 2019, the Federal Communications Commission (FCC) opened the spectrum between 95 GHz and 3,000 GHz for experimental use and unlicensed applications to encourage the development of new wireless communication technologies Following this trend, it is inevitable that mobile communications will utilize the terahertz (THz) bands (i.e., 0.1-10 THz) in future wireless systems. The THz band includes an enormous amount of available bandwidth, which will enable extremely wideband channels with tens of GHz-wide bandwidth. This could potentially provide a means to meet the 6G requirement of Tbps data rate. Considering the advance of related technologies, we expect that 6G would need to be designed to utilize up to 3,000 GHz
Novel antenna technologies
To cope with the difficult propagation characteristics of THz band, it may be natural to enhance the massive MIMO technology that was introduced to support millimeter wave (mmWave) band in 5G. Since the THz band requires much more antennas than the mmWave band, there may be significantly more practical difficulties.
Evolution of duplex technology
In conventional communication systems, downlink and uplink transmissions occur in a mutually exclusive manner either in time domain (i.e.TDD) or in frequency domain (i.e., FDD). Typically, the downlink and uplink receive fixed allocations of time-frequency resources in practical systems.
There is active research into how to remove the restriction that downlink and uplink must use mutually exclusive time-frequency resources. This restriction is known as the “mutually exclusive” principle hereafter. Allowing overlap between downlink and uplink over the entire time-frequency resource (a.k.a. “full duplex”) can increase system capacity by two times, in theory.
TDD. If deviating from the “mutually exclusive” principle becomes a reality, it would be possible to adapt the duplex scheme in a dynamic manner. This would improve the spectral efficiency as well as the system operation flexibility.
Evolution of network topology
Moving toward 6G, we expect that the technologies related to the above trend will further advance to achieve the following:
- Automated addition, configuration, and optimization of new network entities connected to existing BSs via wireless connections. This will significantly reduce the effort for network planning, and hence, the mesh type network topology can become a major technology for flexible and adaptive network deployment.
- Enhanced mobility support for mobile network entities taking into account the speed of transportation systems that can be a part of the cellular network.
- Enhanced service continuity for user devices served by the network entities, which themselves may be moving and are connected to the cellular network through wireless connections.
Spectrum sharing technology enables the use of spectrum by multiple entities. Exclusive licensees often underutilize licensed spectrum because they do not actively utilize it all the time. Allowing opportunistic use of the underutilized spectrum by others can make the best use of the limited and precious spectrum resources, especially those at low frequency ranges.
These resources are critically important for guaranteeing the seamless coverage of mobile communications, but are scarce. We also observe that regulatory bodies begin to consider deviating from the traditional exclusive spectrum licensing approach to achieve better utilization of the limited spectrum. Considering such trends, spectrum sharing technology is worth paying attention to.
This is the right time to work towards use of AI in wireless communications. This effort and progress towards 6G, will result in native support of a comprehensive AI system to realize more efficient, more reliable, and low cost communication systems.
Consider the concept of split computing that makes use of reachable computing resources over the network. These computing resources could be available on various entities of networks, e.g., mobile devices, BSs, MEC servers and cloud servers. With split computing, mobile devices can effectively achieve higher performance even as they extend their battery life, as devices offload heavy computation tasks to computation resources available in the network.
To guarantee high QoE for interactive services with high data rate and low latency requirements, it is important to maintain deterministic E2E latency and to minimize jitter at the microsecond level. High-precision network (HPN) is a solution to achieve this, when paired with massive connectivity supported by both radio link protocols and protocols above radio link.
In order to realize HPN, the following key features should be considered: multi-pathing, multi-homing, and dynamic mobility. Multi-pathing enables usage of multiple alternate network paths and thereby offers improved reliability and optimal usage of bandwidth resources. Multi-homing is the capability of the end device to connect via multiple interfaces simultaneously. Multi-homing requires support for multi-pathing.
An initial expectation of the 6G timeline.
Samsung anticipates that the earliest commercialization could occur as early as 2028 while massive commercialization may emerge around 2030. This is after taking into account the trend of speeding up the development of technical standards for each new generation, They expect ITU-R will begin the work to define a 6G vision in 2021.