RFID: A Solution 100 Years in the Making
The IoT could finally permit RFID to reach its full potential.
A "solution waiting for a problem" is a label often affixed to technologies and inventions. It's perhaps one of the harshest judgements the world could pass, after all the time and care and emotional energy that gets poured into its creation. Yet it's a risk any developer must accept. Often, we cannot know for sure that our pet project will take off in any way – much less that it will achieve the incredible success we have seen in some cases over recent years: Google, cellphones, ARPANet....
RFID has been a labor of love for many generations of engineers. It's probably impossible to credit a single inventor, although the Russian scientist Leon Theremin – who, in 1919, created the eponymous contactless musical instrument credited with inspiring modern synthesizers – is often cited. His passive listening device, later dubbed "The Thing," enabled Russian intelligence services to hear private conversations held in the US embassy in Moscow from 1945 until 1952. For those seven years, it remained embedded in a hand-carved ceremonial plaque – the Great American Seal – that had been presented as a gift to the ambassador and hung on his office wall. Russian teams would activate the device by aiming a radio transmitter at the plaque from outside the embassy building. Without its own radio transmitter or power source, The Thing foiled bug-sweeping techniques of the time. The game was up only when British radio journalists from the BBC alerted staff after finding they could hear American voices interfering with their broadcasts.
RFID continued to mature as a technology, and applications evolved throughout the remainder of the century. Only in the 1990s were standards established. Although now assessed as an $11 billion market, with healthy prospects for double-digit growth, RFID remains little understood to the world outside: tech-savvy consumers who "get" the technologies behind smart living – 5G, mobile payments, e-ticketing, facial recognition – often have little concept of RFID and its capabilities.
Despite its success in an arguably narrow field of application, so much more is possible. Is it a solution waiting for a problem? That could be about to change, thanks to the passive nature of RFID tags. Running off the excitement energy provided by the reader, the tag requires no built-in power source. And that answers issues that are incredibly important to us today. Tags can have an effectively indefinite lifetime, requiring no maintenance such as battery changing or recharging. This makes managing even an extremely large field of deployed devices relatively easy. They can be used anywhere, and – extremely important today – disposal is simple with no consequences for the environment due to the degrading of discharged batteries. It sounds like the perfect sensor technology for the IoT.
Many of today's RFID applications involve pointing a handheld reader to interrogate tags in a manufacturing or retail logistics setting. Flipping that model, so that the tags are roaming and give up their data as they pass static readers placed in specific locations, helps IoT application developers address the perennial question of how to power and maintain large numbers of remote sensors.
Numerous tracking applications can be implemented – and scaled – at a relatively low cost. These could include monitoring the locations of employees within a large site such as a mine or a farm, to protect their safety, simply by tagging industrial clothing. No need to invest in large numbers of expensive personal transponders, such as Bluetooth or LPWAN transceivers, to distribute, maintain, and accept the costs of loss and damage. Similarly, visitors to a large indoor or outdoor attraction can be cost-effectively tracked for safety and geofencing, as well as marketing purposes like measuring the relative popularity of the available experiences.
In addition, by leveraging angle-of-arrival techniques, it is possible to identify the positions of RFID tags – and hence people or objects – within a space. It becomes much more cost-effective to authenticate ourselves with smart systems. Room lighting and heating can activate and automatically adjust to our personally preferred settings. Of course, there are other ways to accomplish these capabilities. The concepts are well-explored by people like the scientist and advocate of implant parties, Kevin Warwick, aka Captain Cyborg.
It's the passive, power-free nature of RFID that's empowering and could make this happen. We can envisage a future in which it is normal for humans to have an implanted RFID tag. The absence of any battery chemicals simplifies biocompatibility, and the freedom from maintenance is also attractive. There is the flexibility to update personal data, such as new access permissions within a building or endorsements on a driving license. The Swedish company Biohax International has offered a similar vision, developing implantable NFC technology for personal identification to ease access to services like banking, payments, transport, and social benefits.
These applications raise valid concerns, giving the opportunity to track and identify individuals everywhere they go. Serious ethical questions are associated with permanent, obligatory tagging. Some control must be afforded to the wearer and access to any data must be securely restricted.
Even so, the opportunities are exciting for those who are actively engaged in bringing these ideas to life. Within the PCB industry, our substrate knowledge can contribute to the development of new and better ways of making tags. Some applications may require tougher materials. In others, there may be an argument for biodegradability. I recently read about microwave-proof food tags that can identify the dish so that the oven can self-adjust to cook the contents to perfection.
As with many of the technologies we develop, we can expect great benefits for our lives. On the other hand, there are challenges to the freedoms that we value so much and should seek to protect.
is technology ambassador at Ventec International Group (ventec-group.com); alun.morgan@ventec-europe.com.
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