Why the Future-Proof Factory Will Rely on Smart Connectivity

Summary

“Future-proof” is a word that shows up a lot of places. But what does it really mean?
 
“It’s difficult to make predictions,” said baseball great Yogi Berra, “especially about the future.” The future is full of surprises–but we still tend to extrapolate in a straight line from what we know today. That is a near-sure bet on being wrong. A better bet is to assume the future is unpredictable but to make decisions that insulate us from bad outcomes. Planning the future of a manufacturing facility offers some valuable opportunities.
 

From inflexible to flexible

Today’s manufacturing industry, and the distribution systems that get products into customers’ hands, are ripe for digital transformation. Companies want to benefit from greater automation of operations but also need to gain greater agility in responding to market demand. That can be a challenging combination, in which every new investment in inflexible infrastructure creates new risk. Reducing the risk of a bad outcome means giving infrastructure the flexibility to adapt.
 
That’s one reason why wireless private networks are experiencing massive growth. Analysys Mason predicts that the number of private LTE/5G networks worldwide will grow from 4,000 in 2022 to more than 60,000 in 2028. A high-bandwidth, highly reliable private wireless network eliminates–in theory at least–a host of issues. Forget about cabling or wiring when making decisions about facility changes. Free up teams to move themselves and their connected technology wherever it’s needed.  Introduce or expand a fleet of autonomous robots for stocking supplies, moving product, or delivering tools. Integrate it all on the fly in hours instead of weeks.
 

From Wi-Fi to CBRS

Until recently, organizations had two choices when it came to private wireless: a Wi-Fi network operating in unlicensed bandwidth in 2.4 GHz, 5 GHz and 6 GHz radio bands, or Citizens Broadband Radio Service (CBRS) in the 3.5 to 3.7 GHz bands.
 
Wi-Fi has been widely adopted, with some 600 million devices sold.  The frequency band is free to use and the standardized access points are inexpensive and easy to install. Many applications can benefit from Wi-Fi, but with so many  networks running everywhere, there is a great deal of opportunity for interference between them and that affects performance. Moreover, in wide areas where multiple Wi-Fi Access Points (APs) are needed for coverage, roaming will likely be needed in-between; a feature that Wi-Fi is not necessarily the best. The above translates to Wi-Fi not being the ideal technology for some mission critical applications in the automation industry. In addition, widespread deployment has also given hackers considerable experience in penetrating their defenses.
 
These shortcomings are behind the rising popularity of CBRS 4G/5G cellular for high-demand private networks. Private cellular networks are more secure and face less interference than Wi-Fi. The band was originally allocated only for government use but was opened in 2019. While it is free to use, every CBRS network must register with a central online database, aka Spectrum Access System (SAS), and the frequencies are only available if no licensed government or ISP user has priority in the area. SAS can cause disruption to some applications if the wireless transmission link is interrupted to change frequency channel.
 
Both technologies are challenged by the complex space in most factories, full of radio-absorbing metal structures and machinery. Getting high performance from them requires extensive  planning of coverage, capacity and interference. If greater automation and agility are the future of manufacturing, that planning will need to be repeated for each change to the facility.  That’s not a good definition of “future-proof.”
 

From many cells to one

There is a need to rethink the fundamental design of cellular private wireless networks. The standard cellular design consists of many radios spaced so that they form overlapping cells of radio frequency. In mission critical applications the multi-cell deployment could be a requirement not necessarily for coverage, but for spatial reliability, i.e. signal being blocked from one cell but clear from another avoiding disruption of service. While this is desirable, it results in dense deployment of cells which operate independently. That creates boundaries between said cells, and that can create trouble. Boundaries in dense deployments mean interference at the edges and tricky handover. It is common to see in this setting the device ping-pong between few cells, or incomplete handovers, and that disrupts wireless connectivity. Devices clustering in relatively small physical locality, for example in the case of Bots recharging or getting serviced, adds  another layer of  intricacy. In this case many devices will be served by one cell which has to  divide the available bandwidth among them, and as a result, both throughput and latency suffer.
 
The ideal network then would consist of a single “supercell,” that is boundary free or almost free.  In this scenario, all radios transmit to and receive from all user equipment (UE) at the same time without interfering with each other and without handovers. This resolves the issues of reliability and service disruption. If the technology also enables scaling in throughput as the cells are added, each UE will have the potential to access the total bandwidth of the network with no congestion in a single cell. The same ideal network would use radio units already available in the market and interface seamlessly with established user devices.
 
It sounds like a fantasy. But technological innovations like this are the product of innovators who have already made many fundamental contributions to mobile technology, from LTE to femtocells. Complying with standards from the Third Generation Partners Project (3GPP) and Open Radio Access Network (ORAN) standards, we have the ability to use software running on generic compute to provide the complex synchronization and calibration that a supercell requires. And it is this reliance on software innovation, with all its agility and flexibility, that future-proofs the factory, no matter what that future may hold.