6G Wireless Communication System: Concept, Architecture, Enabling Technologies and its Future Perspectives

With advancements in telecommunication technologies at a rapid rate, the 6G mobile communication technology era is not as far as it seems.

Wireless communication generally refers to transferring information between any two points that are not physically connected. A mobile phone is an instant messenger by which we can communicate with anyone, anytime and anywhere across the world.

The birth of mobile wireless communication technology took place somewhere in the 1970s with 1st generation technology. From there on, we have progressed by 1G every 7-11 years with 2G, 3G,4G and finally 5G technology that has much higher bandwidth than the former ones.

Mobile radio telephones are the predecessors of today’s modern cellular mobiles. These are generally referred to as zero generation systems provided with a transmitter and a receiver. In between 2G and 3G, there is another generation called 2.5G and 2.75G but they didn’t bring any revolution.

In between 3G to 4G, there was 3.5G, 3.75G and 3.95G which performed better than the original 3G. With 4G and 5G comes 4.5G (5GE), 4G LTE, LTE advanced pro, Zero 5G and 5GNR (New-Radios).

The following table will highlight the transverse wireless generation technology has made since its launch in 1979 –

Timeline from 1G to 5G
Wireless
Communication Generation Technology
Features Relative SpeedYear of Launch 
1GFor calling purposes only2Kbps1979
2GSend text messages,  pictures and MMS15 times faster than 1G1991
3GInternet-based applications50 times faster than 2G2003
4GHD video streaming and multiplayer gameplay. 
50-500 times faster than 3G2009
5GSetting up smart spaces via 5G technology and automationUpto 25Mbps connectivity speed.Supports Virtual Private Network and can load and share internet content in real-time2019
6GAI-Driven wireless communication tools & personalized network experience
100 times faster than 5GExpected to launch around 2030

Each successive generation of mobile communication technology has brought significant improvement in multitenancy networking, perfecting the usage of the previous generation and optimizing the newer technologies in the current one.

6G Technology – Vision and Potential

6G technology is expected to be 10100 times faster than 5G and will be able to support transmission rates of 1 terabyte per second. This technology is also expected to make greater use of the distributed radio access network (RAN) for improved spectrum transmission.

Besides operating at higher frequencies, lower latency and different spectra than 5G, this sixth-generation wireless communication technology will surprisingly help in meeting the demands of a fully integrated net-based system.

6G is expected to roll out by 2030 and become thoroughly operational by the year 2035.

From 5G to 6G
Source: forbes.com

Through its advanced sensing and massive interconnectivity, 6G will connect a wide spectrum of consumers, devices, vehicles, cellular surfaces and Wi-Fi implants.

High-performance interconnections that fulfil diverse service requirements even under extreme density and dynamic environments is what we are aiming for. Increased network coverage, improved network security, positioning accuracy and system reliability are some of the other promises 6G is bringing along with it.

Limitations of 5G are narrow global coverage, availability at specific locations and not being able to support the new innovative applications. 6G enhances the network coverage and will support the higher number of device connections. Other drawbacks of 5G include inter-cell Interference, absence of efficient medium access control, security and traffic management issues.

Already half-built 6G chips support 10 times more devices and are said to be 10-100 times more reliable in terms of connection, signal transference, mobility and coordination among different varieties of multifunctional devices. Enhanced Mobile Broadband (eMBB), Energy-Efficient Strategies (EES) and Massive Machine Type Communication (mMTC) are expected to be the face of mankind in the near future.

Main Objective of 6G

Integrating Earth-imaging satellite networks with telecommunication, navigation, resource monitoring, global positioning, multimedia networks with high-speed internet for faster connectivity and mobile usage is 6G’s key objective.

6G mobile communication technology is going to connect and make a multitude of devices with discrete functionalities interact with one another in real-time space.

How will 6G Work? Which Technologies will Become the Driving Force?

According to our recent research, the 6G technology will be working by selecting different frequencies by adjusting them accordingly. This is possible since molecules and atoms can emit and absorb electromagnetic radiation at characteristic frequencies.

6G is soon going to benefit various technological inspired sectors once it gets into the business. Out of all the progressive technologies, the most important ones that will become the driving force behind the emergence of 6G are the terahertz (THz) band, Artificial Intelligence (AI), optical wireless communication (OWC), 3D networking, unmanned aerial vehicles (UAV) and wireless power transfer (all capitals or no one).

6G supposedly will be an all-coverage network that will pave the way for a ubiquitous connection for space, air, ground and underwater communications.

Required Technological Advancements

As you know 6G will give a strong boost to the existing 5G technology. So, it will undergo some special upgrades that are essential for further technological development. The following are the most essential ones –

6G Technological Advancements
  • Dense Networks By Reducing the Cells’ Size: Cells size becomes a key factor when it comes to making effective use of the available spectrum. Reducing the cell size will help in harvesting the potential of 6G technology fully.
  • Millimetre-Wave Technologies: A wider channel bandwidth requires the use of a higher frequency spectrum. With further development in this arena, we will be able to streamline the data speed and bandwidth required for 6G.
  • Waveforms: In the case of wireless communications, Waveforms lay the ground foundation. A type of digital transmission that is used for successful 4G and 5G mobile communications is OFDM (Orthogonal Frequency-Division Multiplexing) and some 5G+ systems as well. Nevertheless, it does have some limitations so cannot definitely be an ideal choice for our futuristic 6G technology. Other waveforms named GFDM (Generalized Frequency Division Multiplexing) and UFMC (Universal Filtered Multicarrier) can also be used in place of OFDM for providing more flexibility to the 6G mobile communications.

Enabling Technologies and AI

Enabling key technologies will help in the consummation of beyond 5G (B5G) and 6G communications with next-generation high-performance computing solutions.

This will ultimately lead the way towards the development of next-generation edge supercomputers. These technical advancements will possibly assist us in the realization of our goals and a better understanding of 6G architecture. Some of them are listed below:

  • Holographic communications or transmissions
  • Extended Reality (XR) – VR (Virtual Reality) + AR (Augmented Reality) + MR (Mixed Reality)
  • Autonomous Unmanned aerial vehicles (UAV)
  • Big Data Analytics
  • Quantum Computing/Quantum Machine Learning (QML)
  • Blockchain Cryptography
  • Teleoperated Driving
  • Tactile internet (TI)
  • Dynamic Network Slicing
  • IoTs (Internet of Things) to IoEs (Internet of Everything) and Automation.
  • Machine learning and Cognitive Networks
  • Three-Dimensional Networking (3D)
  • Haptic Communication
  • Proactive caching which includes management for OLAP objects
  • Industry 4.0
  • IoBNTs (Internet of Bio-Nano Things)
  • Digital Replica or Digital Twin
  • Millimeter-Waves Communication for 6G
  • Centralized Radio Access Network (C-RAN) based on Cloud Computing
  • Photonic integrated circuit technology (PIC)
  • Terahertz Frequency Wireless Spectrum for 6G
  • Optical Space-Division Multiplexing (SDM)
  • Softwarization and Virtualization (SDN & NFV)
  • Multi-core fibre (MCF)
  • Beyond Massive MIMO
  • AutoEncoder
  • Integrated Satellite-Terrestrial Networks
  • Transformative Connective Intelligence from “connected things”
  • Radar Technology Integrated with Mobile Technologies
  • Cloudification/Fog/Edge Computing
  • Small Cells Communication
  • FSO (free – space optics) Fronthaul/Backhaul Network
  • Integration of Wireless information and Energy transfer (WIET)
  • Free duplexing and spectrum sharing (FDSS)
  • Connected Robotics and Autonomous systems
  • Optical Wireless Technology
  • Industrial Automation 
  • Radio-Over-Fiber (A-RoF) and (D-RoF)
  • BCI (Brain-Computer Interactions) technology boosted Five-Sense Information Transfer and Cognitive Computing 
  • Massive Multiple Input, Multiple Output Technique (MIMO)
  • Cell-free Heterogeneous Communications
  • Integration of Access-Backhaul Networks
  • A QoS( Quality of Service)‑Aware Spectral Efficient network
  • Integrated Sensing and Communication Technologies
  • Atmospheric Satellites(VLEOs) and High-Altitude Platforms (HAPs)
  • Backscatter Communication
  • Wireless- AI fusion

6G will enhance the decision-making ability of automated systems by facilitating services that can be intelligently controlled by “n number” of advanced technologies and data enablers: smart transportation, transforming reality, behavioural analysis taking help of big data and remote health monitoring.

Sixth Generation Network Architecture

The sixth-generation network architecture will revolve around these seven parameters –

⭕ Air Interface

To interact at these given frequencies, an optimum balance should strive between spectrum performance, network coverage and power efficiency usage. Both NOMA (Non-Orthogonal Multiple Access) and RSMA (Rate-Splitting Multiple Access) currently rely on successive interference cancellations (SIC) thoroughly responsible for decoding every information for their users.

This schema needs to be reconsidered and fully developed before practical deployment. Researchers have modelled an AI-based software interface that uses an intelligent air-interface switching system for the User QoS (Quality Of Service) Enhancement.

6G Technology Architecture
Source: researchgate.net

⭕ New Spectrum

As the beamforming algorithms are not mature enough, the use of the mmWave, THz band and visible light spectrum simultaneously for networking have been proposed to solve our problems. These bands have not yet been experimented with but have the potential to operate at a higher frequency.

The telecommunication signal does get attenuated rapidly with the distance travelled hence we will combine Massive Multiple Inputs and Multiple Outputs (MIMO) together with beamforming to get the desired output with the above-described spectrum.

⭕ Coexistence of Variable Radio Access Technologies

6G communication will be designed in a manner that all Wireless Communication Technologies with the help of Artificial Intelligence (AI) integrate with cloudification, softwarization, slicing and virtualization into one.

The outcome may be the world’s best designed ubiquitous networking infrastructure that will incorporate Wi-Fi, Bluetooth, UWB (Ultra-wideband), unmanned aerial vehicles biosensors, VideoLAN Client (VLC) and all satellite communications into a centralized 6G communication network.

⭕ Machine Learning and Artificial Intelligence

From instantly managing the resources to deriving the best solutions as per the user requirements, 6G wireless communications will be independently making decisions with Enhanced Security, Machine Learning (ML) and Artificial intelligence (AI). Due to increased complexity in operations, smarter devices with inbuilt features and revised technologies, intelligent agents will be needed to detect anomalies and repair functions as well.

Machine Learning and Artificial Intelligence

⭕ Advanced Beamforming with Very Large Scale Antenna (VLSA)

Advanced beamforming is to converge the beam to the desired direction or user. The transmission range thus increases because the beams are concentrated in only one direction minimizing energy loss in each and every way.

⭕ Orbital Angular Momentum (OAM)‑Aided MIMO

The transmission of multiple data streams over the same spatial channel by OAM (Orbital angular momentum) has many advantages over other beamforming techniques. OAM can have an unlimited number of orthogonal modes. These allow multiplexing data and streaming them across a single channel.

This will result in increasing the spectral efficiency, transmission capacity and long-distance line-of-sight (LOS) coverage. QAM supports in mode division multiple access (MDMA). This means QAM flexibility to be used in narrowband and wideband frequency can be an attractive scheme for low probability of interception (LPI) applications.

⭕ Intelligent Reflecting Surfaces (IRSs)

IRSs are composed of thin electromagnetic materials that reflect the EMR (electromagnetic rays) in such a manner that they get configured by the system software. IRS can form the base for beamforming in 6G because these surfaces enhance the signal-to-interference-plus-noise-ratio (SINR) without altering the infrastructure or imposing any hardware constraints on the communication networks. Intelligent reflecting surfaces can replace the conventional relays due to their added abilities to operate in the deep-fade and non-line-of-sight (NLOS) communication environments.

Challenges Faced for Beyond 5G Communications

Several technical problems need to be solved before 6G communication systems implementation become successful:

1. High Propagation with Low Absorption of THz

A new architecture has to be drawn and implemented for the THz communication systems. The transceiver must be able to operate at high frequencies and should be able to make full use of very widely available bandwidths. This also means maximum data transfer over relatively long distances without any propagation loss and atmospheric absorption of the signal in-between.

Health and safety concerns which include planning an effective area for distinct THz band antennas also need to be taken into consideration and planned effectively before the proper implementation of 6G wireless communication networks.

2. Complexity in Resource Management and Designing for 3D Networking

A new network design needs to be constructed for scheduling. Techniques for resource management need to be revised and optimization for mobility support, routing protocol, and multiple access to user equipment (UE) is quite essential for proper interception and dissemination of the data.

3. Autonomous Wireless Systems

The 6G network will give the required support to automated systems that include autonomatives, UAVs and Industry 4.0 based on AI. To enable autonomous wireless systems there is a need to converge together many heterogeneous sub-systems, autonomous computing, interoperable processes, machine learning, autonomous cloud with heterogeneous wireless web and machines of systems.

4. Modelling of Sub-mmWave (THz) Frequencies

These futuristic mmWave and sub-mmWave terahertz frequency band – propagation characteristics are subject to changing atmospheric conditions. Hence no perfect channel model has been yet planned out with the ever-changing absorptive and dispersive effects.

5. Device Capability

With the introduction of several new features, existing devices especially smartphones should be able to integrate Tbps throughput, AI, XR, and integrated sensing with enhanced communication features.

The compatibility of these 5G devices to the 6G network is still an issue. This compatibility will save a lot of money and make it easier for all users to harness this technology potential to the fullest.

6. High-Capacity Backhaul Connectivity

The access networks in 6G will have a very high density and thus it becomes necessary to improve the capacity of these networks. The backhaul networks in 6G must handle the enormous volumes of data for connecting between the access networks to each other and the formed core network to support high-data-rate services at the user level.

The multi-optical fibres with FSO backhaul networks will help us strengthen the connectivity in every possible manner.

7. Heterogeneous Hardware Constraints and Sub-Systems

In 6G, there are a huge number of heterogeneous types of communication systems such as frequency bands, communication topologies and antennas for speedy service delivery.

RF filters, amplifiers and many other subsystems will get involved and have to be designed in accordance by integrating all in a single segment after overcoming the complexities Moreover, the access points and mobile terminals will be significantly different in the hardware settings. Such devices will require variable packet sizes to be transmitted and chip size will also get increased.

8. Spectrum and Interference Management are Preliminary

Management becomes necessary for the greatest resource utilization with the quality of service maximization. For the successful implementation of 6G, researchers have concerns as to how we can share spectrum and manage these mechanisms in heterogeneous networks. Investigations are ongoing regarding synchronizing transmissions on a single frequency with cancelling all parallel and successive interferences simultaneously.

9. Beam Management in THz Communication

Beamforming through massive MIMO systems might seem a promising technology however efficient management is still a tedious task in itself. High data rate communications will only be achieved when hurdles in the propagation of the terahertz frequency get overthrown with the optimized high-speed optical beam.

 10. Physical-Layer Security

Security, secrecy, and privacy are expected to be the key features of 6G networks. As a consequence, a new physical-layer privacy technique needs to be developed for Big Data and AI-based future 6G communication. Physical-layer security design and interactions with all other layers hold paramount importance in 6G.

Physical security technologies and quantum key distribution via VLC are vital solutions to provide security in 6G. Large-scale quantum computing can multiply the efficiency of current systems with the massive development of edge and cloud infrastructures supported with asymmetric cryptography Utilization of machine learning for automated security in the 6G networks, virtualization and softwarization will also help in detecting and preventing attacks on the encrypted data in an optimal way.

11. Variable Radio Resource Allocation

A variable radio resource has to be assigned to each user according to their devices with variable QoS requirements. Variable bandwidth allocation, power or both vary from system to system. Another challenge is to develop steady, faster and precise algorithms that can take the overall control of the 6G communication aspect of wireless signaling without becoming rapidly attenuated and having a high penetration even at THz frequencies.

12. Ultra-Low Power & High Processing Circuit Design

Communication in Automated cars and Health-mediated software applications need to be completed in assigned time duration. To achieve low latency with security (eRLLCS) in milliseconds that too with ultra-high reliability becomes, data packets should get transmitted in a short span without any processing delay. Thus, it is quite essential to develop 6G wireless systems that will integrate powerful high-end processors for reliable transmission. The objective of the exercise is to consume low power with mMTC and enhanced security features.

Planning and implementation with respect to the economic perspectives of this technology will definitely consume time. Accessing Network Congestion with Traffic Management would be another.

If we become successful in our endeavours, we will soon observe a hyper-connected world full of exciting prospects evolve in front of our naked eyes!

Applications and Services

The 5G technology has its vast importance and application once it came into existence. That’s the same condition with the 6G. Integrating terrestrial, satellite and airborne networks into a single wireless communication system is crucial for the culmination of 6G networks.

It is leading to a massive change in the technology sector and becoming useful in various technological applications. Here we have mentioned some of the key applications and services where it is going to be used for good efficiency and for complete global coverage in 6G communications.

  • Enhanced Data Security and Mobile Broadband
  • Holographic verticals
  • Wireless power transfer
  • Ultra-long battery life coupled with advanced battery technology 
  • Efficient energy-harvesting and utilization
  • Communication to space and deep-sea
  • Life quality improvements 
  • V2X (vehicle-to-infrastructure) communication
  • Telemedicine
  • Revolutionize the Health Care sector
  • Voice assistants
  • Fully e-Automated Machines that can self-organize and self-optimize
  • Advanced Robotics
  • Features and facial recognition
  • Fully automated cars
  • Established decision-making procedures in law enforcement areas and social-credit systems
  • Quality control measurements
  • Air, Water and all toxicity sensing
  • Smart wearables and Implants
  • Computing Reality Devices
  • E‑health and digital biosensing
  • Will result in Military, Commerce and Scientific advancements
  • Change the face of Agricultural and Recreational Sector
  • Surveillance and Delivery
  • 3D mapping and Aerial photography
  • Disaster management, Natural Calamities and Threat detection
  • Drone racing and aircraft technology improvement
  • Satellite to Satellite Communication and Satellite Internet
  • Sea to Space Communication
  • Smart homes, offices, cities and villages
  • Cybernetics
  • Optimising mass-public transportation
  • Eliminate time and space barriers through remote operations
  • Biometric-based applications including fingerprints and voice recognition
  • Eye-tracking and brainwaves
  • Home and bank automation
  • Online gaming services
  • Space technology and defence applications will be modified with 6G networks.

Verdict

Survival without technology is inevitable and up-gradation predestined. To assist the next generation tech, we need the next generation networks as well. The 5G towers we have supports future upgrades so we won’t have to completely replace them for 6G.

advanced technologies

Overcoming the limitations of 5G and enabling advanced technologies with 6G is the Goal. 6G is expected to be fully operational by 2035. The upcoming communications network fabric will be a convergence of all the above-listed technologies, nanocore, high-performance computing (HPC) and artificial intelligence (AI).

This will take place in a way that all the network operators will become connected to one single core. We hope 6G energy efficiency will be at par and in favour of mother nature. How? That remains to be seen.

6G As A Big Game-Changer of Future

6G will lay the foundation for the future of technology and its advancements. This evolution will make use of digital tools to transform education, industrial and health sectors to a large extent. 6G wireless technology will open vast origins in the manufacturing, transportation and defense equipment industries. It will indirectly or directly result in economic growth, smart homes and efficient energy harvesting mechanisms.

Researchers claim a sixth sense experience for humans and machines with proficient sixth-generation technology. AI will also be the main driver of mobile technology and the 6G will be the enabling force behind an entirely new generation of applications shaping the communication networks of the future.

The building of a bridge that binds Biology and Artificial Intelligence can be materialized with this technology. Apart from rapid collaborations in new technologies on vast scales between intelligent agents to solving intricate challenges off the cuff, 6G will provide extensive solutions to complex problems with large data volumes and high throughput in an environmentally-sound manner.