How RFID, NFC, and Sensors Solve Industry Challenges

Tailoring an RFID IC to specific customer requirements or needs enables innovative and highly specialized solutions. Semiconductor manufacturer EM Microelectronic, for example, has developed the world’s smallest and thinnest RFID tags, measuring 1.6mm x 1.6mm with a thickness of 150µm.

This was achieved by integrating an IC core on silicon wafers in combination with a coil-on-chip antenna. The result is a complete tag solution on wafer with a near field communication range of approximately one centimeter. Such a compact form factor is highly advantageous for applications that require minimal space while still providing reliable near-field performance.

A booster antenna can be integrated to extend the tag’s range up to four meters, enhancing its functionality for use cases such as PCB track-and-trace in industrial, automotive and aerospace applications. This is an example of an application where an extremely compact form factor is essential. In this scenario, the booster antenna can be printed directly on the PCB, with the RFID IC mounted on the same board. This design maximizes range and enables identification and tracking capabilities while maintaining an extremely compact profile.

Such configurations demonstrate how custom RFID IC solutions can be applied to highly specialized use cases in various industries.

Because industrial projects have large infrastructure investments and long life spans, this often results in a mixed supply chain management infrastructure where UHF RFID operating in the 860 to 960 MHz band is used for certain processes, while HF RFID tags address specific needs in others.

In this context, different technologies are critical to meet the unique needs of different industries. Dual frequency technology has emerged as a transformative solution, bridging the gap between different systems and enabling companies to optimize operations in diverse environments.

EM Microelectronic was the first to bring dual-frequency chips to market with the RAINFC chip combination. The em|echo was introduced in 2016 and was replaced in 2020 by the second chip generation: the em|echo-V.

However, applying these technologies across different use cases is not without its hurdles. Technologies designed for specific applications, such as retail, often fail to meet the unique and demanding requirements of industrial use cases.

With longer decision cycles, lower production volumes and highly specific requirements, industrial sectors often face challenges when attempting to adapt off-the-shelf RFID solutions. This underscores the importance of tailored approaches to ensure the effective implementation of technologies in industrial applications.

The next section of this article will focus on specific use cases for UHF RFID and dual frequency technologies.

The rail industry presents unique challenges for RFID deployments, particularly in scenarios involving long lifecycles and changes in ownership of assets such as train wagons. Unlike consumer products, rail vehicles require reconfigurable Electronic Product Codes (EPCs) to adapt to new ownership or operational requirements in different countries. This challenge has been addressed in a collaboration between semiconductor manufacturer EM Microelectronic and the Swiss Federal Railways (SBB).

SBB has been using UHF RFID for more than a decade. The railway company is gradually building an efficient system around the technology for continuous condition monitoring and maintenance planning of its rail vehicles.

UHF RFID is used for high-speed (250 km/h), long-range vehicle identification, while NFC technology is now being used for maintenance operations.

Typical use cases for UHF RFID in rail maintenance, repair, and operations (MRO) include wheel load and hot box detection, acoustic measurement systems for axle and traction motor bearings, wayside wheelset measurement systems, and confirmation and billing of automated vehicle exterior cleaning.

On the other hand, SBB uses NFC technology for underfloor lathes and similar production machines, portable wheelset measuring systems in the workshop, confirmation of technical checks and interior cleaning in marshalling yards, registration of corrective work orders in operations and maintenance.

A critical requirement is to ensure accurate identification of individual components, such as bogies or wheels, which are often swapped between vehicles during maintenance operations.

Maintenance records need to be associated with these components, rather than the train itself, to support effective lifecycle management. A combination of UHF RFID and NFC technology is used for vehicle and component identification in maintenance and in the supply chain. The result: real-time diagnostics of rolling stock and 100% vehicle identification.

In practice, SBB maintains a digital twin of each train in its ERP system, which is key to predictive maintenance. SBB is currently using UHF RFID and QR code technology. QR codes are currently used to identify components during maintenance. However, QR codes often become soiled and difficult to read. This led SBB to investigate NFC as an alternative solution.

One of the key benefits of this use case is data consistency with the shared memory architecture and seamless access via both UHF RFID and NFC interfaces. This eliminates the need for duplicate programming during maintenance operations.

EM Microelectronic’s new em|echo-I chip integrates a larger tag memory, which is often required when seamless network connectivity is not available in the application. With larger memory comes the challenge of accessing data efficiently. As a solution, the recent Gen2v3 standard on the UHF side provides new capabilities such as dynamic power adjustment for improved tag identification and system efficiency.

It is also fully backward compatible with existing readers. With the introduction of the em|echo-I as a full Gen2v3 product, EM Microelectronic is driving the adoption of the new standard and has provided SBB with future-proof solutions for long-term reliability and performance.

Similar to the industrial sector, healthcare presents unique challenges for inventory management and process automation due to the complexity of its supply chain and critical operating environments. Dual-frequency technology can be used to address these challenges.

For example, WaveMark, a division of Cardinal Health, has deployed both UHF and HF RFID solutions across the healthcare supply chain, from large-scale inventory tracking to point-of-use applications.

UHF RFID is primarily used for supply chain and inventory management, providing long-range and high-volume reading capabilities. Meanwhile, HF RFID is used in smart cabinets and operating rooms. In the surgical environment, HF RFID enables automated documentation of equipment usage, verification of expiration dates, and identification of recalled items. This not only minimizes medical errors, but also potentially saves lives. The data collected is simultaneously logged into patient records, ensuring accurate documentation and reducing administrative burden.

RFID and sensor technologies are widely used in automotive manufacturing, particularly for monitoring critical environmental and operational parameters. Capacitive sensing, a key application in this sector, can be used to detect potential water leaks during the production process. It also facilitates real-time monitoring of machine or engine performance by detecting overheating events.

A real-world example is the multi-temperature digital indicator developed by Thai electronics company Cleantech and Beyond, which integrates the em|aura-sense chip. This technology is used to detect overheating in engines. Capacitive sensors embedded with advanced RFID chips can accurately measure temperature changes.

This is achieved by incorporating materials that exhibit capacitance changes in response to environmental parameters such as temperature fluctuations. This allows the tag to detect temperature changes through capacitive sensing. The tag is also available in an NFC or QR code variant.

A key advantage of this system is the irreversibility of material changes when exposed to extreme temperatures. This ensures that any temperature excursion is recorded, even if the RFID tag is not actively powered. This battery-free design allows for continuous monitoring. In addition, the system provides both visual feedback-through a color change in the material for personnel inspections-and digital data that can be efficiently read during routine inventory scans. The captured sensor data can then be integrated into enterprise resource planning (ERP) systems.

Another application for capacitive sensing with RFID is environmental monitoring in agriculture. This is where greenhouses get smart.

In practice, capacitive sensing technology is ideal for detecting soil moisture levels, which enables precise irrigation management. Semiconductor manufacturer EM Microelectronic, for example, has teamed up with Microsensys to develop an innovative tag for soil moisture sensing. The em|aura-sense tag is planted with each plant. The tag enables continuous monitoring of soil moisture levels in real time.

This capability allows automated irrigation systems to optimize water delivery to each individual plant based on its specific needs, reducing resource waste while ensuring optimal growing conditions.

Studies have also shown that UHF RFID tags with capacitive sensors have been used to monitor landslides. The sensor tag is planted near the surface of the soil. By monitoring the water content of the soil in at-risk areas, the likelihood of a landslide can be predicted and appropriate evacuation or safety measures can be taken in advance to prevent disaster.

RFID technology, when integrated with sensor-based solutions, can also be used to address complex operational challenges, such as pick-by-light applications in data centers and similar environments. Identifying specific components, such as a faulty cable flagged by an IT system, can often be challenging, especially in dense or disorganized environments. To simplify this task, RFID technology can be adapted to integrate visual indicators directly into the system.

Standard RFID ICs can be reconfigured to integrate application-specific requirements. For example, LEDs can be associated with specific cables or components.

Once the unique identifier (UID) of the desired item is provided, the system activates the corresponding LED, visually pinpointing its location. This approach greatly simplifies the retrieval process and reduces the time required for maintenance or troubleshooting.

Trust is the foundation of any business, and secure solutions are essential to building trust. Security is critical in every industry, and RFID technology plays a critical role in protecting applications from counterfeiting and unauthorized access.

From retail and pharmaceuticals to automotive and industrial, counterfeit and unauthorized parts can have serious consequences, compromising both quality and safety. To address these challenges, RFID IC solutions are often customized to integrate advanced security features and communication protocols tailored to specific customer requirements.

Embedding cryptographic functions in UHF RFID tags is a complex process that requires a combination of expertise in both security and low-power operation. These tags often incorporate algorithms such as the AES Crypto Core and other specialized protocols, such as the one time password algorithm, designed for unique applications such as Web authentication and secure access control.