B5G and 6G Wireless Technology

6G: Building Tomorrow's Wireless Tech Beyond 100 GHz

- The Key Building Block of 5G

3GPP stands for Third Generation Partnership Project. 3GPP has previously defined specifications for third generation Universal Mobile Telecommunication System (UMTS) and fourth generation long term evolution (LTE).  ITU is the International Telecommunication Union. A network is said to be a 5G network if it can meet International Mobile Telecommunications (IMT)-2020 performance requirements. 

3GPP defines fifth-generation (5G) cellular technology in Release 15 to meet ITU's IMT-2020 performance requirements and to support various services related to usage scenarios such as enhanced mobile broadband (eMBB), Ultra-reliable Low Latency Communication (URLLC) and Massive Machine Type Communication (mMTC). 

Example 5G performance requirements are 20 Gbps peak data rate, 1 ms radio network latency, 10 Mbps/m² area throughput, and 1 million (low-rate) IoT devices per square kilometer. The key building blocks of 5G are the New Radio (NR) air interface, new radio and core network architecture, virtualization and automation technologies, and new equipment. These building blocks enable 5G to deliver targeted 5G services.

- 5G Evolution - On The Path to 6G

Sixth generation (6G) wireless communication networks promise to integrate land, air and maritime communications into a robust network that is more reliable, faster, and can support a large number of devices with ultra-low latency requirements.

Researchers across the globe are proposing cutting-edge technologies such as artificial intelligence (AI)/machine learning (ML), quantum communication/quantum machine learning (QML), blockchain, terahertz and mmWave communications, tactile internet, non-orthogonal multiple Address access (NOMA), small cell communication, fog/edge computing, etc. as key technologies to achieve beyond 5G (B5G) and 6G communication.

Is 6G real? Yes. And no. Yes, 6G (or whatever it’s eventually called) will eventually replace 5G, but 6G is not yet a functioning technology, and is instead in the early research phase. Mobile telecom companies are much too focused on 5G to deal with 6G in any significant way, although early research projects have begun thanks to funding from governments that want to gain an edge.  

How fast will 6G be? We don’t know how fast 6G will be yet, but estimates have it around 100 times faster than 5G. The final standards that will define what a 6G connection is will probably be down to the International Telecommunication Union (ITU). The ITU recently nailed down the standards for 5G (which it refers to as IMT-2020) after more than eight years of work, and is expected to start a similar process for 6G soon.

It’ll be like 5G, but more so. Even higher speeds, even lower latency, and masses of bandwidth. Researchers and scientists are talking about 6G going beyond a “wired” network, with devices acting as antennas using a decentralized network not under the control of a single network operator. If everything connects using 5G, 6G will set these connected devices free, as higher data speeds and lower latency make instant device-to-device connection possible. 

- Technology Development from 5G to Beyond Fifth-generation (B5G) Networks

New developments in wireless communications are advancing rapidly. Although 5G has just officially entered the commercial market, many designers are developing new 6G-related technologies.

5G technology has reached the transmission level with a peak rate of 10Gbps and a low latency of 1 millisecond. Because its bandwidth is greater than 4G, it can be connected to more smart devices at the same time. However, there are still technical limitations in the application of 5G. Therefore, B5G/6G is integrating wireless communication and satellite communication to achieve the goal of global seamless coverage and interconnection.

The application frequency bands of B5G/6G are in the range of 0.1~0.3THz and 0.1~10THz respectively. This frequency band is called the terahertz frequency band. 

Advantages of the terahertz band:

• Abundant Spectrum Resources
• The peak transmission speed reaches 100Gbps~1Tbps
• Indoor positioning accuracy reaches 10 cm/outdoor 1 meter
• Communication delay 0.1 ms
• Ultra high reliability
• The density of connected devices reaches more than 100 per cubic meter
• Since there is no space absorption loss problem in the terahertz frequency band, it has the advantages of fast transmission speed and long transmission distance. It can be applied to inter-satellite communication and can provide greater coverage.

Antenna technology is one of the key technologies developed for wireless communication, dealing with radio and light waves at terahertz frequencies. Millimeter and terahertz waves are attenuated by rain and absorbed by oxygen and water molecules, making them unsuitable for long-distance radio communications. This poses formidable challenges in the selection and processing of antenna materials and structures.

- The Evolution of B5G/6G Systems

6G Internet is expected to be commercially available by 2030. The technology makes greater use of distributed radio access network (RAN) and terahertz (THz) spectrum to increase capacity, reduce latency and improve spectrum sharing.

Due to the widespread growth in the number of Internet of Things (IoT) devices, next-generation communication systems are designed to achieve high spectral and energy efficiency, low latency, and massive connectivity. These IoT devices will enable advanced services such as intelligent transportation, environmental monitoring and control, virtual reality (VR)/virtual navigation, telemedicine, digital sensing, high definition (HD) and full HD video transmission in connected drones and robots . With IoT devices expected to reach 25 billion by 2025, existing multiple-access technologies struggle to accommodate such a large number of devices. 

Even the fifth-generation (5G) communication systems currently being rolled out globally cannot support such a large number of IoT devices. The 3rd Generation Partnership Project (3GPP) is already working on the development of 5G standards and has identified Massive Machine Type Communication (mMTC), Ultra Reliable and Low Latency Communication (URLLC) and Enhanced Mobile Broadband (eMBB) as the three main Use the 5G case in Release 13 (R13). 

At the same time, algorithms are being developed for next-generation communication systems that will outperform existing 5G networks. A typical 5G communication system can support up to 50,000 IoT and/or Narrowband IoT (NB-IoT) devices per cell. Specifically, stronger networks must be designed to enable massive access beyond 5G (B5G)/6G communication systems.

[Budapest, Hungary - mindz_eye]

- B5G Networks and Edge Intelligence

Beyond fifth-generation (B5G) networks, or so-called "6G," the next generation of wireless communication systems will fundamentally change the way society develops. 

Edge intelligence is emerging as a new concept with high potential to address new challenges in B5G networks by providing mobile edge computing and edge caching capabilities and artificial intelligence (AI) close to the end user. In the B5G network enabled by edge intelligence, edge resources are managed by artificial intelligence systems to provide powerful computing processing and massive data collection locally on the edge network. 

Artificial intelligence helps to obtain efficient resource scheduling strategies in complex environments with heterogeneous resources and a large number of devices, while meeting the ultra-low latency and ultra-high reliability requirements of new applications such as autonomous vehicles, remote operations, and intelligent applications. Transportation systems, Industry 4.0, smart energy, e-health and AR/VR services. 

By integrating AI capabilities into the edge network, the radio network becomes service-aware and resource-aware, providing a complete understanding of the operating environment and the ability to dynamically adjust resource allocation/orchestration. 

However, despite the potential of edge intelligence, there are many challenges that need to be addressed in this new paradigm. So far, there has been limited research work on edge intelligence in B5G networks.

- New Spectrum and Frequencies with 6G

6G requires massive performance improvements as compared to 5G. While 5G was designed to achieve peak speeds of 20 Gbps and utilize frequencies up to 100 GHz, 6G is expected to achieve data rates of up to 1000 Gbps and utilize frequencies up to 3 THz. Latency is also expected to be improved massively with air latency targeted to be around 100 μs, end-to-end (E2E) latency of around 1 ms which would be result in user experience latency of less than 10 ms. User experience latency is the sum of all latency components in the entire communication channel.

Just as the jump from 4G to 5G represents an expansion of spectrums used and introduction of new frequencies, so will the evolution between 5G and 6G communications. Whereas 5G leverages mmWave in the microwave frequency range, 6G will take advantage of even smaller wavelengths at the Terahertz (THz) band, which is typically referred to as 100 GHz to 3 THz.

By exploring the capabilities of wireless signals in the largely unused range above 100 gigahertz -- or the proposed 6G spectrum - can enable applications outside the classical definition of communications. The tiny signals at this range, referred to as millimeter waves, or mmWaves, can allow for imaging, mapping, localization and higher data-rate communications to connect multiple devices and even applications that haven’t yet been invented.

- New Challenges with 6G

The 6G wireless communication network is expected to integrate the terrestrial, aerial, and maritime communications into a robust network which would be more reliable, fast, and can support a massive number of devices with ultra-low latency requirements. 

Just as there have been, and will continue to be, many challenges with 5G, so will there be many new challenges with 6G.  One of those challenges will be developing commercial transceivers at the to-be utilized THz frequencies. This is largely an area in which electronics component providers will need to innovate. For example, semiconductor providers will need to deal with extremely small wavelengths and correspondingly small physical size of RF transistors and how they will interwork with element spacing of THz antenna arrays.

The researchers around the globe are proposing cutting edge technologies such as artificial intelligence (AI)/machine learning (ML), quantum communication/quantum machine learning (QML), blockchain, tera-Hertz and millimeter waves communication, tactile Internet, non-orthogonal multiple access (NOMA), small cells communication, fog/edge computing, etc., as the key technologies in the realization of beyond 5G and 6G communications. 

- Potential New Applications of 6G

Features of the 6G spectrum will make for some interesting applications and multiplicative effects. Potential applications for Terahertz spectrum include sensing, imagine, wireless cognition, For example:

• Wireless cognition: Robotic control and drone fleet control;
• Sensing: Air quality detection, personal health monitoring, gesture detection and touchless smartphones, explosive detection and gas sensing;
• Imaging: See in the dark, HD resolution video radar, Terahertz security body scanning;
• Communication: Wireless fiber backhaul, intra-device radio communication, connectivity in data centers, information shower;
• Centimeter-level positioning.

6G will have big implications for many government and industry approaches to public safety and critical asset protection, such as the following: 

• Threat detection
• Health monitoring
• Feature and facial recognition
• Decision-making in areas like law enforcement and social credit systems
• Air quality measurements
• Gas and toxicity sensing, and
• Sensory interfaces that feel like real life

Improvements in these areas will also benefit smartphone and other mobile network technology, as well as emerging technologies such as smart cities, autonomous vehicles, virtual reality and augmented reality.

- The Future of Global Satellite Broadband Networks

6G is expected to integrate with satellites. Integrating terrestrial, satellite, and airborne networks into a single wireless system will be crucial for 6G. 

Orbital broadband networks will need large constellations of small satellites to relay transmissions effectively and at lower power consumption than today’s larger satellites. This is where the technologies of wireless transmission absorption and refraction – known as frequency selective surfaces (FSS) – come to play a major role in increasing efficiency over any previous satellite wireless technology. 

FSS are used in Earth observation satellites to separate signals, which are collected by single reflector antennas. For these, FSS provide broadband remote sensing capability by enabling the instrument to work over a large frequency bandwidth. So, one instrument replaces many that were required in the past, thus reducing the footprint of each satellite (useful for nanosatellites) or [packing] more equipment onto a larger platform. FSS are an optimal solution to be used for future satellite broadband communications systems.