While 5G has only shown a fraction of its potential, will the world ever be ready for the next generation?
Much of the world seems to have changed beyond recognition since the pandemic began. With numerous economic and environmental uncertainties, however, one thing remains constant: our appetite for what comes next – and our impatience – are undiminished. The rollout of 5G cellular networks has barely begun – after a huge development effort to define the standards and do the engineering – yet, already, excitement is building around 6G. The first standardization phase for this will begin in 2023 and services should be available around 2030.
Some of us remember the arrival of the first digital cellular networks, in 1993. This was the point when MNOs were able to begin offering data services in addition to voice. Data rates were laughable by today’s standards, starting at about 9.6 kbaud. Some of today’s dominant trends, however, such as remote working, can trace their origins back to here. With these primitive data services, we were able to use our phones to connect remotely to factory data systems and do rudimentary work wherever we were.
Today, 2G data services are perfect for connecting IoT devices and for M2M communication, although network operators are keen to switch off legacy infrastructure to concentrate resources on 4G and 5G services for consumers. It’s likely that 3G turnoff will be completed first. Certainly it will in Europe, where 2G services could be maintained until 2030 or beyond.
Right now, many are uncertain what advantages 5G will bring. We know it will support high data rates and very low latency, and it’s also clear that delivering the most advanced 5G services to rural areas will be a great challenge due to the nature of the signal physics and infrastructure requirements. 5G requires many more access points, which can be installed far more easily in urban areas by mounting on lamp posts and other street furniture, whereas the practical challenges, and the costs, are greater in rural areas
We can safely assume that 6G will be even bigger and better, with faster data speeds and such low latency that the smartphone screen will be the single largest source of lag in the system. It may be hard to imagine now, but the time this arrives we will be ready for the new services that will emerge.
Some of the most powerful applications that could take advantage of 6G’s speed and scale include modelling large systems like entire cities digitally, using billions of sensors to gather data and actuators to allow control of the system.
It may become technically feasible to manage the world as a single system, to digitally track production and waste, and manage access to goods and services to ensure inclusion and protect the environment. While this could enable us to achieve social goals that recognize the interdependencies between people and our overall dependence on the planet and its finite resources, it would be critically reliant on machines that can detect and respond to our actions almost instantaneously. Some freedoms we enjoy today have been born in the counter-cultures of previous generations, and clumsy programming of those machines could stifle any further social evolution. Personally, I have always seen advanced technologies like these as empowering for humanity, particularly in their ability to support better healthcare and to help focus industrial activities. The prospects for handing instant agency to autonomous machines could indeed see the IoT and AI become a great threat to humanity.
While contemplating what 6G could mean for humanity, we also need to consider our industry’s role in realizing the infrastructure and terminal equipment. In the PCB industry, we have already begun to analyze key technology drivers and likely responses in terms of PCB performance and laminate characteristics. I’m fortunate to be engaged in this with leading infrastructure companies and recently attended an event that went into some detail about the likely impact on PCB design, laminate properties and manufacturing processes. Expected key demands include larger PCBs, increased temperature capability while ensuring stable loss characteristics, and tighter tolerances. With larger PCBs will come greater reliability challenges due to CTE mismatch between components and the substrate. The industry must also seek new materials that have very low losses at multi-gigahertz frequencies, without overheating or incurring excessive signal loss. Right now, PTFE is the lowest-loss material class we have, although we will need alternatives that have multilayer capability. Critical properties will include dielectric constant (Dk) below 3.0 and dissipation factor (Df) better than 0.003, while the preparation of copper foils capable of handling signal frequencies of 50GHz and higher will require careful consideration. At the same time, manufacturing tolerances on parameters like line width, layer-to-layer registration, and impedance are expected to be at least 50% tighter.
Today’s 5G rollouts are the culmination of an incredible engineering achievement that has driven our technical capabilities to new heights. 6G will represent another enormous leap forward and many are sure to question whether we need – or even want – such an all-pervasive and potentially all-knowing and autonomous network so closely connected with all aspects of our lives. Many ethical questions are likely to arise. We are only beginning to find out what 5G can do for us. When our engineering is ready to realize 6G, I’m sure we will be more than ready for the services it will enable. •