Category: Industry Insights

About the author

15Teemu Ainasoja

I am VP, Sales and Marketing at Voyantic. I have over 15 years of experience from the RFID industry in Europe and the USA. I have two master's degrees: in industrial engineering and in marketing, and two patents in auto-ID technology. I am actively participating in RAIN RFID alliance activities.

Content

Emerging Technologies and Expanding Applications – A Look into RFID Research in 2023

Jun 26, 2024

RFID research in 2023 shows how fast the technology is evolving beyond its traditional use cases. Recent studies explore new application areas, improved tag and antenna designs, smarter sensing capabilities, and advances that push performance, reliability, and sustainability further than before. From logistics and retail to healthcare, smart materials, and emerging IoT use cases, academic research continues to play a key role in shaping what RFID systems can do next. This article takes a closer look at the most interesting RFID research topics of the year and what they signal for the future development of RFID technology.

The following analysis examined the headlines of RFID research articles published in 2023 in Google Scholar. There has, undoubtedly, been an impressive selection of fascinating research topics, which means I can’t include all topics and papers in this analysis even if I wanted to. But let’s look at some of the most exciting topics and trends of 2023.

Application-oriented research seems to be on the rise, which is understandable given the industry’s growing and maturing. RAIN RFID use is expanding rapidly to include volume use cases outside of retail, such as healthcare, logistics, manufacturing, and many other fields. Application research supports this market development.

Research expanding from technology development to technology use is a positive sign. The spread of types of applications tells about the applicability of RAIN RFID in several areas.

RFID Sensing in Healthcare

Integrating RFID technology, sensors, and medical diagnostics advances biomedical sciences to a whole new level. This is an interesting and growingly versatile RFID research area.

Passive UHF RFID technology could detect problems with orthopedic fixators early.

On-metal Tag Design

Following the trends of previous years, several papers have been published on developing tags specifically for tagging metallic objects.

Passive RFID sensors

Batterylessness is highly popular when it comes to passive RFID sensors.

Ancient findings and artifacts from ancient city.
RFID sensors could be used to monitor the microclimatic conditions in a museum

Coupling Effects

The following studies indicate that understanding and optimizing coupling effects are crucial for enhancing RFID tag performance in various applications.

RFID Applications

Papers examining RFID applications are, not surprisingly, a rising research area.

Conclusions

In conclusion, the RFID research published in 2023 demonstrates significant advancements in various fields, including healthcare, pharmaceuticals, and intelligent transportation systems. These studies highlight the expanding applications of RFID technology, from improving medical diagnostics and monitoring to enhancing the efficiency of industrial processes and urban infrastructure. The ongoing innovation and diversification in RFID applications underscore the technology’s growing impact and potential for future developments.

About the author

51Antti Paukkunen

I'm a long-term Voyantician and an Engineering Fellow at the Company focusing on RFID technology and testing methods. Before joining Voyantic in 2011, I was working at Aalto University as a researcher in the field of Applied electronics and Biomedical engineering.

Content

EPC Gen2 UHF RFID Standard v3 – What’s Changed and Tips for Hands-on Testing

Mar 04, 2024

EPC Gen2 UHF RFID standard v3 update was recently published by GS1. The new version came with optimizations in the air interface and new commands aiming at saving time, improving accuracy, and making the inventory process more robust. In this blog, we’ll walk through some of the most significant changes in terms of inventory performance, and provide pointers on how to get started with testing and learning yourself.

More time (and power) for the chip initialization

The minimum carrier time before the first command has been increased from 1500us to 2500us. The change comes with a small compromise on total initialization time but also works for the benefit of chips which require more time to initialize. The delay is likely small enough to go unnoticed in most applications and the extra time should secure the proper initialization of all chips. Moreover, interrogator power-up is required to be faster (500us → 250us) with more allowance for undershoot and overshoot (+/-5% → -10/+20%) during the 1ms waveform settling period. The shorter rise time is unlikely to influence chip performance significantly and the greater allowance for overshoot opens up an interesting possibility to provide a short carrier level boost (1.58dB/1ms) as part of the field initialization. This kind of boost won’t change the active state operating voltage of the chip but might help them to further optimize their performance during initialization process, and ensure optimal performance of tags.

Fig. Interrogator power-up is required to be faster, but field strength is allowed to undershoot/overshoot by -10%/+20% during the 1ms waveform settling period. The total time before command was increased to 2,5ms. Source: https://ref.gs1.org/standards/gen2/3.0.0/

Field-strength adjustment filters out fringe tags

The third update on the air interface is to allow interrogators to perform field strength adjustment during Select, Challenge, Query, or QueryX commands in an attempt to prevent ghosting tags from slowing down the inventory process. Ghosting tags, also referred to as fringe tags, are tags that have such a low operating voltage, that they might get activated and respond to Query, but do not have enough energy to follow through the response to Acknowledge command. Such tags cannot be inventoried, but since they will reply to Queries, more iterations are required in the inventory process, and the time to complete the inventory cycle gets increased.

The interrogator performs the field adjustment by dropping the carrier level by 0-20% (0-1,93dB) for the duration of the command modulation. The level is adjusted down at least 500us (RF Adjust lead time) before the start of command and brought back up monotonically at the end of the command. Tags are required to tolerate such a waveform pattern and guarantee that the minimum power needed to complete the response to Acknowledge is not more than 1,93dB higher than the power needed to start replying to QueryX. In effect, with the field adjustment in use, the tags shouldn’t have enough power to respond to the adjusted Query/QueryX command unless they’re capable of replying to Acknowledge as well, which reduces the unnecessary overhead from the inventory process.

Fig. Field-adjust before Query/QueryX (upper) and after Query/QueryX/QyeryY (lower). Field-strength adjustment can be used to bring Query sensitivity closer to Ack sensitivity which may help reduce ghosting tags and improve inventory efficiency through the reduction of unnecessary iterations. Source: https://ref.gs1.org/standards/gen2/3.0.0/

New commands further improve filtering and allow simpler memory access

QueryX and QueryY, combine classic Select + Query commands in a single timed package. Unlike Select(s)+Query, they’re effectively packaging the whole series of Selects and the following Query into a single command frame. This blocks external readers from interfering with the filtering process and makes the inventory process more robust. It also prevents tags from participating if they only heard part of the QueryX/QueryY command frame. This could be the case if they’ve been moving in/out of the reader’s field of view during the inventory cycle. Lastly, the new commands come with optional configurations such as an option to choose whether the tag shall include EPC or TID into the ACK response (AckData), whether RN16 is protected with a checksum (ReplyCRC), and flexible filtering conditions: ≥, ≤, ≠, = (Comp). These parameters add flexibility to the inventory process and can be used to make the process more efficient.

Fig. QueryX/QueryY commands effectively package Select(s) + Query into a single command and provide new parameters for more efficient and robust inventory process. (click to enlarge image). Source: https://ref.gs1.org/standards/gen2/3.0.0/

ReadVar, is an alternative to Read (which also remains mandatory in the standard). The two are very close to each other, but the tag reply to ReadVar contains additional informative data. NumWords indicates number of words returned as part of the reply, MoreWords indicates the amount of data yet available in the memory to read beyond the read space, and there’s a parity bit computed over data transmitted (Parity). Overall, ReadVar command is more flexible in comparison to Read and makes tag memory access easier as the user doesn’t need to know the available memory size of the bank targeted.

Fig. ReadVar is a more flexible version of the classic Read command.
Source: https://ref.gs1.org/standards/gen2/3.0.0/

Use custom commands to test new protocol features

Tagformance Pro comes with an option to utilize user-defined custom commands in tag performance tests providing a practical means for testing some of the new Gen2 v3 features. Custom commands can be created using a standard text editor, imported to the software, and used in the performance test programs. For example, it’s possible to generate a custom Query command waveform with field adjustment and testing the effect on tag performance using Threshold sweep (see figures below). Furthermore, a custom command can also be combined with ISO 18000-63 inventory into a custom command sequence, which allows preparing e.g., ReadVar test command.

Fig. Custom command feature allows generating used-defined command waveforms which can be utilized in standard test programs, such as Threshold sweep. (Left) Normal Query waveform Query, (right) Query with field-strength adjustment and 500us RF adjust lead time.
Fig. Measurement example – Query threshold with and without field adjustment. Read sensitivity threshold provided as a reference to give an idea of difference of Query vs. Query+Ack sensitivities of the tag tested.

For more information on the updates discussed in this article and other important changes in the protocol, go to the new version of the protocol on GS1 official website. Of particular interest might also be Snapshot sensor reading procedures which were mainly mirrored from ISO-18000-63. Also, remember to check what’s new in the Tag data standard to stay current with the latest changes in the tag encoding.

Download – Example Custom Command Package ›

Presentation – Extend Tagformance Testing Capability with Custom Commands

Download a quick overview on Tagformance Pro Custom Commands feature including application examples.

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About the author

42Anirudh Wali

I am a Senior Product Manager, passionate about leveraging technology to drive innovation and solve complex challenges in the RFID industry. With a customer-centric approach, I lead cross-functional teams to deliver cutting-edge solutions that exceed market expectations

Content

Lot Management in RFID Tag Production – Essential Machine Requirements

Feb 08, 2024

Over the past few years, Voyantic has successfully implemented the Tagsurance 3 quality control system across multiple RFID tag production lines. These integrations not only enable the highest standards in tag manufacturing but also shed light on the positive advancements within the RFID industry. One notable development is the growing synergy between lot management and quality control. For an RFID production manager or quality manager, understanding the quantity of perfectly functioning tags in a delivery is far more meaningful than just having a count and yield percentage.

Incorporating lot management is more straightforward and cost-effective when done in conjunction with the purchase of new production machinery, rather than attempting to implement it post-machine deployment on the factory floor.

What is lot management? 

Lot management revolves around the concept of a known quantity of deliverables from a specific process step. In the realm of RFID label production, a lot typically corresponds to one roll of labels.

A closely related term is “job.” A job refers to an operation dedicated to producing a specific type of product for a customer or an internal order. Importantly, the process and output remain consistent throughout a job, which may encompass one or multiple lots.

The terminology is easiest to explain with some pictures.

Relation of a lot to an order from a customer, and a job in production.
A lot is typically the same as a roll.

Before starting a job in the Tagsurance GUI, it is possible to define the lot. The lot definition includes details such as.

  • Are all tags counted, or just the good ones? 
  • Is counting across lanes, or on a single lane? 
  • Is the lot change marked with a cut mark?
  • What should the machine do when the lot is complete?

Lot management

In a typical production setup, where delivery and production are roll-based, lot management includes:

  • Producing rolls with the desired quantity of labels,
  • Understanding the quantity of tags within each roll, and
  • Generating and reporting relevant data for each lot (each roll)

Tagsurance 3 system role in lot management

Tagsurance 3 quality control system plays a pivotal role in the seamless lot management in RFID tag manufacturing. It employs a sophisticated approach to decide whether an individual tag should be counted in the production result set, leveraging comprehensive test data to ascertain the number of tags produced on each lane, differentiating between good and failed tags.

One of the distinctive features of the Tagsurance 3 quality control system is its granular understanding of the location of each tag on the production line. It precisely tracks the lane and the distance from a trigger sensor in millimeters, providing essential position information. This combination of counts and position data serves as the cornerstone for effective lot management.

Given that the Tagsurance 3 quality control system possesses a wealth of information, it becomes the logical and secure choice to entrust with lot management. An alternative approach could involve transmitting count and fail status information to other machine components, such as the machine PLC. However, this introduces unnecessary complexity and potential risks. In high-speed production lines, even a minimal delay in data transmission (from Tagsurance 3 to machine PLC) carries the risk of misaligning counts by a single tag.

The optimal and most efficient solution is allowing the Tagsurance 3 quality control system to take charge of lot management for the following reasons:

  1. Precise Quantity Tracking: Tagsurance 3 is equipped to accurately determine the number of tags in a roll.
  2. Comprehensive Reporting: Tagsurance 3 generates and reports relevant data for each lot, providing a comprehensive overview of passed or failed tags.

When the Tagsurance 3 system manages the production lot information, the risk of split-brain problems between different systems is eliminated. Additionally, Tagsurance 3 offers the flexibility to provide precisely timed signals before, on, or after lot completion, ensuring a smooth and synchronized production process. This level of integration not only enhances operational efficiency but also mitigates the potential risks associated with data transmission delays in a fast-paced manufacturing environment.

Cut mark

The cut mark serves as a practical tool in lot management, providing a visual demarcation between the end of one lot and the commencement of the next.

Cut marks indicated in Tagsurance 3.

Tagsurance 3 system seamlessly integrates with the manufacturing process, triggering the device responsible for creating cut marks. In many instances, the same device used for marking failed tags is employed for printing cut marks as well.

What does the machine need to handle?

While the Tagsurance 3 system handles various aspects of lot management, the tag manufacturing machine still plays a critical role, particularly in the precise execution of cutting tasks to create the desired rolls.

There are different ways to do this: 

  1. Automatic turret rewinders 

Some machines incorporate automatic turret rewinders, presenting an efficient solution. In this setup, the production job operates continuously, and rolls are automatically cut to the correct size. This automation eliminates the need for manual roll changes by operators.

  1. Cut mark and manual cutting

In certain scenarios, manual or semi-manual cutting methods prove to be a better alternative. Safety considerations often drive this choice, as automatic cutters need to be well-shielded for the safety ofrom human operators.

In a manual or semi-manual process, the machine halts when the liner reaches the cut position, such as at a splicing table. The operator then manually cuts the liner before seamlessly continuing the process with a new output roll.

https://youtu.be/1M4SVh5I2OU?si=VT3-2XRcrJmjzk50&t=12
This video shows an example of a Turret Rewinder by GM where, at the end of a lot, the machine first slows down and stops, and then an operator cuts the web and finally restarts the machine.

Selecting the appropriate cutting method depends on factors such as safety requirements and the layout of the roll handling area. Whether through automated turret rewinders or manual cutting processes, the tag manufacturing machine’s role in achieving precision and efficiency ensures the delivery of high-quality RFID tags.

Must-have machine features for seamless integration

One indispensable feature that facilitates the seamless integration of lot management with automated testing solutions is a digital IO (Input/Output) input, acting as a control mechanism for the manufacturing machine.

Stop signal input

For efficient lot management, there is a need for precise and controlled stopping mechanisms. Particularly in high-speed machines, abruptly halting operations may compromise accuracy, leading to challenges such as incorrect cutting positions on automatic turret rewinders or misalignment at the splicing table. The inclusion of a digital IO input allows for a controlled cessation of the machine, ensuring accuracy and reliability in the manufacturing process.

Slow down signal input

In practical terms, high-speed machines benefit from a gradual slowing down process before coming to a complete stop. This gradual deceleration is vital for intricate operations, such as ensuring precise cutting positions or accurate alignment at various stages of production. The machine’s ability to receive a digital IO input for initiating the slowdown process enhances the overall control and precision of the manufacturing workflow.

The machine slows down before stopping.

Serial port interface alternative for stop and slow down signals

While digital IO inputs serve as the standard for most machines, it’s worth noting exceptions, such as the utilization of a serial port interface in certain models like the Muhlbauer DDA machines. However, in general, the industry standard leans towards the effectiveness of digital IO inputs for optimal control and coordination between lot management and quality control systems.

Nice-to-have machine features for improved efficiency

Two features that significantly contribute to this efficiency are Cut Mark Capability and Operator Signal Integration.

Cut mark capability

Having a discernible cut mark on labels proves invaluable for human operators, especially when machine stopping accuracy is not within a few millimeters. This visual indicator aids operators in clearly identifying which labels belong to the previous lot and which are part of the next one. Even with automatic turret rewinders, the presence of a cut mark provides operators with peace of mind regarding the correctness of quantities.

The Tagsurance 3 system excels in this aspect, precisely triggering the cut mark at the right position. This feature not only enhances accuracy but also empowers operators with a clear demarcation between lots, ensuring seamless continuity in the production process.

Operator signal

Efficient lot management extends beyond just machine capabilities; it involves effective communication with operators. Even in the case of automatic turret rewinders or manual cutting scenarios, alerting operators when a lot is nearing completion proves invaluable. This proactive approach allows operators to prepare for tasks such as cutting the liner and changing the roll promptly, minimizing machine downtime.

The Tagsurance 3 system takes the lead by providing timely signals, either on lot completion or even a predetermined quantity before completion (e.g., 500 labels before the lot concludes). These signals can be utilized by the machine to trigger visual alerts, such as signal lights, or audible notifications through loudspeakers. This integrated communication ensures that operators are well-informed and can take prompt action, contributing to a more streamlined and efficient RFID tag manufacturing process.

Signal lights alert the machine operator.

Strategic considerations for a label manufacturer to optimize lot management

The seemingly minor features within the production machinery play a pivotal role in the seamless execution of lot management. Features such as

  • slow down signal input,
  • stop signal input,
  • serial port interface on some Muhlbauer DDA machines,
  • ability to print cut marks and,
  • ability to signal the operator

might appear subtle, but their absence can pose challenges in implementing effective lot management.

When investing in a new label manufacturing machine, ensure that lot management-related details are explicitly specified. The absence of connectors and signaling means can prevent lot management from working optimally. As RFID technology evolves, these features become indispensable for RFID production and quality managers seeking to elevate standards and achieve greater efficiency in the tag manufacturing process.

Connect with us to learn more about Tagsurance 3 lot management features and integration into production machines.

Request a Tagsurance 3 Demo

About the author

21Jesse Tuominen

I joined Voyantic as a partner in 2005 to design Voyantic's first commercial product, and I've had a front-row seat since then to see how the RAIN technology has evolved and matured while bringing my own contribution to it. As a background, I have a MSc level in electronics after which I made my PhD in the field of photonics. UHF RFID slots nicely between these two worlds and they offer a lot of perspective into my work. Currently, as the CTO of RFID technology, I work with new measurement methods, RF design, proofs of concept, standards, protocols, industry collaboration and IPR.

Content

RAIN RFID Tag ICs – The Road to Configuration Words

Nov 21, 2023

Tag config memory –  What is that? Is it a fifth memory bank? Having configuration words in tag memory is the new normal in the industry and it is slowly gaining importance and cannot be ignored any longer. How did we end up with config words and how can we embrace them instead? Let’s take a look.  

Birth of Gen2

The core features and the operating principles of a RAIN tag IC have remained the same since the birth of the protocol in 2004 – The ability to wirelessly read and write memory contents, the ability to lock all or parts of the content from further edits by outsiders, and the ability to permanently disable the transponder when it has served its purpose.  That was pretty much it and to a great extent, still is.

The memory was organized into four parts all with their special purpose. Also, in the air interface protocol, a total of two bits were reserved to specify which memory was to be selected, read, written, or locked.

Memory bank 00 is the “reserved memory” and it contains the 32-bit Kill password as its two first words and the 32-bit Access password for the following two words, four 16-bit words in total.

Memory bank 01 is the “EPC memory”. This is where the EPC code is stored. EPC code is the specified part and length of the memory that will be broadcasted in the inventory process. The two first words in the EPC code have a special function. The very first word has a precalculated error correction word, CRC, stored in it. The second word, referred to as the protocol control word, or PC-word, is an important one. It is a word broadcasted prior to the EPC code in inventory and has several single-bit flags to tell which features tag has activated, and what numbering system it might belong to. It also has a 5-bit L parameter to tell and set the length of the broadcasted part of the EPC code. In short, in the inventory process, the tag would give a reply consisting of PC+EPC+CRC all from this memory.

Memory bank 10 is the “TID memory”. This has all the unalterable records of the tag locked from the factory in the wafer state. In particular, it has MDID specifying the company that designed the IC and TMN specifying the exact IC type and version.

Memory bank 11, is the “user memory”. This is a memory dedicated for the user to write any other entries the application needs, and should contain no special words or bits for the protocol or IC operation. As only a few applications require this type of “disc space” and most applications work solely around the EPC code, most commodity tags don’t actually have any user memory. Manufacturing expensive non-volatile memory “just in case” is too expensive as it uses quite a lot of  IC surface area.

Typical memory map and memory contents of the four memory banks when read with Tagformance Memory Management tool. The MDID+TMN reveal that this is the memory of a tag equipped with an older monza5 chip .

Rise and fall of the custom commands

Very soon after the very first wave of ICs had hit the market, the second wave of ICs from roughly 2010 and onward had several new features that were not considered in the original memory organization and protocol. However, the protocol had large RFU provisions for custom commands. So, each tag IC got their own set of special vendor and IC-specific commands to activate and control the new advanced features. The tag features were often clearly documented in datasheets and worked well. However, readers, their command sets, and UIs really struggled to keep up with new and specific firmware versions often needed. For practical matters, like controlling the privacy level of retail tags in this somewhat custom and vendor-specific way just didn’t work too well.

Gen2v2 to the rescue

In 2014, the protocol got a new version, the Gen2v2, which included many of the features added earlier as custom in a somewhat more standard way. The main topics that the new version touched were authentication, encryption, and user privileges. This cleaned the table a little, but still, using new commands to access new features was already found to not always be the easiest solution to adopt.

Configuration words

What happened nearly simultaneously with the release of Gen2v2 was that the control of these added features was slowly transferring from specific new commands to standard Select, Read, and Write commands just pointing to special memory locations. Every reader and reader UI already had filters and memory read functions enabled, so these could be “misused” to control tag settings. Specially formulated Select commands were used to trigger events like “record sensor reading” and “switch to temporary operating mode X”. Writing specific control bits changed settings like tag memory allocations and backscatter levels the state of which could be retained in memory from this point on and to be retained through power cycles.

Soon every manufacturer had their own “config memory bank” or “config word” hidden deep inside the already existing four banks with bits and parameters to be configured to tailor the tag functionality.  The trouble was that each IC manufacturer placed the config memory in a different place with varying functionality. Also changing the settings is not always as easy as hailing the tag and writing, as special safety measures are often set in place.

In hindsight, It would have been great to have had a 5th memory bank for tag settings, but as there were just the two bits in each command to specify the memory bank, we were already kind of maxed out at four.

Vendor-specific implementations

Impinj

From roughly the R6 family onwards, Impinj has chosen to place the config word in the reserved memory bank, right after the two passwords at address 0x04. This location has been kept throughout the various R6, M700, and M800 families of ICs with the purpose of each bit being kept more or less similar. Some of the features that can be configured are read range reduction, autotune disable, unkillable mode, and memory split between EPC and User memories, and some inventory optimization modes. More complex ICs like the Monza X-8K have used several words deeper in the same reserved bank for even more settings. Care must be taken when setting the features as only some of the bits can be written, some need to be written from a secured state with a non-zero access password and some bits can only ever be changed once. As the protocol only allows full 16-bit words to be written, changing single bits needs to be done with care and optimally the whole config set on one single write event.

A common reason for changing tag configuration is to trade some of the maximum EPC length into user memory. For instance, the only difference between the M830 and M850 is a different split between the EPC and user memory sizes, and the swap can also be made through the tag configuration bits.

NXP

NXP on the other hand has chosen to primarily use the word at a word address 0x20 in the EPC memory for configuration starting form the Ucode G2iL family of ICs and through the G2iM, Ucode 7, Ucode 8, and Ucode 9. Available features vary from model to model, some of them touching on the topics of product flags, backscatter strength and curve type,  parallel encoding, memory config selection, write power indicator, self-adjust settings, and memory checks. Some of the bits are action bits, meaning that selecting on those will trigger special features, some bits are permanent bits for configuring more permanent modes and some are purely indicator bits for reading current feature status. Changing some of the settings is careful work as some require a non-zero access password, then accessing the tag with that, then strictly using a mandatory Write command to perform a toggle-write on the bits that are wanted to be flipped.

NXP Ucode9 has config bits to select from different backscatter responses which can be helpful to optimize for privacy, performance, or conformance.

EM Microelectronic

EM Microelectronic has been known for their “more involved”, more advanced, and therefore also more complicated ICs hosting a variety of features, such as serial data interface, power outputs, sensoring, IO-pins, NFC+RAIN operation, TOTAL tag talks only modes, etc. These advanced settings often take several words of memory space for configuration in what EM refers to as “System memory” at the far end of the User memory bank.

Alien

Alien has a “Device configuration” often further up the TID memory bank. However, not many public datasheets are available describing the functionalities better. Most probably they are settings performed by the manufacturer and are not meant for the user or an encoding process to mess with. Anyhow, so far four manufacturers and four different memory banks have been chosen for config purposes.

Other manufacturers

With several dozens of Gen2 tag IC manufacturers in the game, there are too many to mention and not all distribute proper open datasheets to share all features in public. However, it seems that some of the newer players on the market have chosen to adopt one of the existing strategies, such as the Impinj Reserved memory word 0x04 for a comparable configuration. This might help existing readers support the newcomers when the location of the settings is the same.

Afterthoughts

There are several good aspects on this topic. First of all, for at least 90% of the customers, the initial settings are just fine. Also, with the two biggest RAIN IC providers on the market covering such a large market share, there nearly are two “standard” ways to control tag configurations. Furthermore, the Gen2v3 is just around the corner (more on that later), but it is not going to touch on the subjects typically controlled by the tag config bits. Unfortunate, that it will not clean this up, but then again fortunate, that it will not introduce even more ways to facilitate configurations that are bound to evolve faster than the protocol versions ever will. The place where the spread and complexity of configuring RAIN tags is putting the most pressure is probably in the encoding of tags where each IC type needs to be recognized and catered for to serve the remaining sub 10% of cases. If your software or UI is not recognizing the IC types, then the datasheet is your friend in deciphering the tag configuration options.

A personal plea to all the RAIN IC manufacturers out there: Please keep the datasheets publicly available to your customers and solutions providers. Also, luckily we are today talking about small single-bit differences in tag configs, as RAIN stands technologically relatively united and nowhere near as spread out and as complicated a disorder as the 13.56MHz playground that NFC is trying to unite and clean up. Let’s continue keeping RAIN united.

About the author

15Teemu Ainasoja

I am VP, Sales and Marketing at Voyantic. I have over 15 years of experience from the RFID industry in Europe and the USA. I have two master's degrees: in industrial engineering and in marketing, and two patents in auto-ID technology. I am actively participating in RAIN RFID alliance activities.

Content

Trigger Sensors in RFID Production – Get It Right

Sep 06, 2023

In the past couple of years, I have been following several projects where the Voyantic Tagsurance systems have been integrated into production machines.  Surprisingly often, the biggest problems have been related to triggering – “seeing” accurately when a label enters the system. The experience even turned into a rule of thumb: “If something does not work correctly, first check the triggering”. I have realized that getting the triggering to work correctly is of utmost importance.

At the same time, I have been pleased to see plenty of new Tagsurance features that help to avoid challenges with triggering.  

In this article, I will discuss:

  • Why it is so critical to get triggering to work perfectly?
  • Why triggering can be difficult?
  • How do Tagsurance 3 features help get the triggering reliable?

Principle of Triggering

All (or most?) trigger sensors work with the same few simple principles:

  • Each sensor has a physical parameter it monitors. Depending on the sensor type the parameter can be the strength of light of a certain color (through a beam sensor), amount of conductive material (an inductive sensor), darkness of view (a contrast sensor), darkness and shade of color in view (a color contrast sensor), and so on.
  • The sensor has a window of view.  It only senses the parameter within this window of view.
  • The sensor is trained/programmed to recognize when the parameter passes a threshold value. For example, if a view of a contrast sensor gradually turns from white to light grey to darker greys and black in the end, the sensor is trained to see a specific point in the continuum as the threshold point.
  • At the threshold point the trigger sensor’s digital output changes from 1 to 0 (or vice versa, or the trigger sends a pulse).
A contrast sensor is designed to see the edge between light and dark areas when the edge passes the window of view. In the sample, the labels have a printed trigger mark to make the triggering easy.

Why does triggering need to be perfect?

Any problem in triggering will affect the overall quality system performance, production machine performance, and production process accuracy and efficiency. Some triggering problems are obvious, some are more subtle.

  • Missed triggers
  • Double triggers
  • Not detecting missing labels
  • Suboptimal timing
  • Suboptimal positioning

If a trigger is missed on a tag, that tag flies through the machine undetected. It would not be tested or otherwise processed. It would not be recorded in production logs. It would not be counted to output quantity. But it would be on the roll and get delivered to the customer – free of charge, of unknown quality, and probably incorrectly processed. With a high likelihood, there would be problems awaiting the customer.

A double trigger is an opposite issue. One label is counted twice and attempted to be tested and processed twice. There is a high likelihood that one or both of the process actions fail. The customer would only receive one label instead of the two that were counted.  Counts, log files, yield data, and so on would be incorrect.

In some processes, a label can be detached from the liner. Recognizing these missing labels can be important for keeping the entire process optimal. The challenge is to notice when a label does not pass the trigger sensor when expected. A bit of smartness needs to be added to the trigger signals.

In RFID label production machines, there are usually only a few milliseconds to test an individual tag. Accurate results are based on the inlay being at the right position on top of the test coupling element when the test is made.  

In this example, a label can move 7 mm on top of the Snoop Pro coupling element while being tested. With 60 m/min lane speed, this gives 7 ms of test time. If 1 mm is wasted because of suboptimal or non-consistent triggering, the test time is reduced to 6 ms (about 14.2% less time available).

Why triggering can be difficult?

The root causes for triggering difficulties vary:

  • One sensor type may not fit each produced material.
  • The “edge” may not be clear enough for the sensor in use.
  • There may be multiple edges per inlay at the path crossing the window of view.
  • When the liner moves, it may also drift across the lane, or vibrate up and down.
  • Materials have imperfections.
  • With fast-moving material, it is not easy to see the exact position of triggering – optimization is difficult.

In RFID label machines typical materials to trigger are:

  • Inlays
  • Cut labels
  • Uncut labels
Cut RFID labels

Cut labels are usually the easiest material with clear edges between the label and out of the label.  Triggering issues may arise, for example, if lighting conditions change. Glossy materials would amplify the difficulty. The issue is that the threshold position within the window of view can drift if the sensor receives a variable amount of light. If the color of the liner is close to the color of the label, detecting the edge may not work with a contrast sensor.

Uncut RFID labels. Note also material being wavy, this is a potential problem for accurate triggering.

Uncut labels without a trigger mark cannot be triggered with contrast sensors. Depending on the material a through-beam sensor or metal sensing inductive or capacitive sensor is needed.

Inlays with no single-edge trigger path (multiple edges per label).
(inlay outline from www.tageos.com)

Some inlays (antenna on a transparent liner) may not have a clear trigger path, but the trigger sensor would fire multiple times per inlay. Sometimes the antenna shapes are small compared to the window of view, in this case, even the smallest drift across a lane could be a problem.

Inlays with a clear trigger path (inlay outline from rfid.averydennison.com)

In label machines lane speeds are typically tens of meters per minute and can be even hundreds of meters per minute. At high speeds, materials start easily vibrating. If the material happens to jump when the edge is in the window of view, there is a risk of double trigger.

Voyantic Tagsurance 3 system has several built-in features that help with triggering.

The Tagsurance 3 system has features that help in avoiding typical trigger problems. When used correctly, the Tagsurance triggering is 100% reliable.

Tagsurance 3 Triggering Features

The Tagsurance 3 features that help with triggering include:

  • Support of multiple sensor types
  • Advanced pattern recognition
  • Simulated triggers
  • Visibility on trigger performance
  • Strobe light

Tagsurance 3 Supports Multiple Trigger Types

Several types of trigger sensors can be used in the Tagsurance system. All these sensors are plug-and-play compatible with the Tagsurance system.

  • Contrast sensors (grayscale or color contrast) recognize differences in color or darkness, such as the edge between a liner and a label, as long as there is a contrast difference.
  • Through-beam sensors sense changes in materials’ capability to pass light, as long as some part of the material passes light.
  • Capacitive triggering senses edges between metal and non-metal
  • Ultrasonic triggers sense differences in material thickness
Several trigger sensor types can be used in the Tagsurance 3 system.

Pattern Trigger

Pattern trigger is a feature that can always be used.  Defining a simple pattern has proven to be an efficient way to avoid double triggers regardless of the root cause. It eliminates double triggers arising from complex antenna patterns, varying light conditions, a vibrating liner, and so on.

An example of a simple pattern trigger settings.

The above picture illustrates settings defining a simple pattern. This pattern replaces a plain edge recognition, by expanding the edge. In this pattern, when the label passes the window of view of the trigger sensor, the sensor must first see 3 mm white, and then 2 mm color (trigger mark). When the defined pattern is seen, the trigger is fired at the actual edge position inside the 5 mm long pattern.

This pattern efficiently eliminates double triggers. If the trigger saw 2 edges – for example, because of liner vibrating, the pattern rule would not be met. This is when simulated triggering comes into play.

Simulated Trigger

In the above settings, the repeat length, aka pitch, is defined to be 25.01 mm, and a simulated trigger is generated after 7 mm has passed from the expected trigger position. The following actions are performed at the expected label position (and not 7 mm off).  

The trigger is simulated if the sensor doesn’t fire as expected, regardless of the reason. Reasons for not triggering could be poor-quality printed trigger marks, missing labels, lane drifting, or trigger patterns not matching the set trigger pattern conditions.

The simulated trigger feature fixes most of the issues causing the trigger sensor not to see the edge as expected.

The simulated trigger feature is also used in detecting missing labels.

Hold-off Distance

Another possibility to avoid double triggers is to set a hold-off distance. With this feature, a double trigger is discarded within the hold-off distance. For example, if a 0.5 mm hold-off distance is set, it eliminates most of the double triggers.

Hold-off distance should be used with caution when used to avoid double triggers in complex inlays.

Use hold-off distance with caution. In the example, an inlay is normally triggered on the first edge, and triggering on the second edge is avoided by setting a hold-off distance (1). But, if a trigger is missed (2), the triggering will permanently go off sync (3).

Visibility into Triggering

Tagsurance 3 system provides visibility on trigger reliability.  The trigger sensor view shows the actual repeat length as seen by the trigger sensor.

Trigger sensor view

In the above example, there is periodically one repeat that is about 0.5 mm longer than others. This 0.5 mm must be considered when optimizing the trigger position. An additional 0.5 mm safety margin must be used.

Trigger sensor view – missing label

In this example, the liner drifted and for a short period, triggers were missed. The scale of the repeat length changes for a while because of the exceptionally long trigger interval. Similarly, double triggers would be observed as exceptionally short trigger intervals.

Strobe Light

For optimizing trigger position Voyantic offers a strobe light that automatically synchronizes with trigger signals. The strobe light flashes whenever a label is in the test position. And because the human eye works as the human eye works, the strobe light shows perfectly where the label is on the coupling element when testing starts.  Optimizing trigger positioning becomes easy.

When the trigger position is adjusted in the GUI, the trigger mark shift can be observed with the help of the strobe light. (Note that the video with frame rate limitations does not do justice to the strobe light, the real-life view is even better)

Recommendations – How to Make Triggering Perfect

  1. Select a sensor type that matches the material.
  2. Use the pattern trigger feature combined with simulated triggering.
  3. Confirm reliable triggering with the trigger sensor view.
  4. Use strobe light to fine-tune the trigger position.

With the above principles, the trigger sensor will work perfectly.

See Tagsurance 3 in Action

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About the author

32Voyantic

Voyantic is a leading provider of testing and encoding systems for the RFID industry. Our solutions are designed to accelerate development, ensure the highest design and manufacturing quality, and ease the adoption of RFID technology.

Content

Why Label RF Quality Matters – Excellence in RFID

Aug 23, 2023

Summary

  • Bad RFID tag production quality = unacceptable variance in tags’ sensitivity = inconsistent performance / read ranges = unreliable RFID system performance = unhappy customers = bad for business
  • Quality can only be checked with professional RFID testing and quality control systems
  • Voyantic can help you improve design and manufacturing quality

Voyantic has published a lot of content about RFID technology, the market, and quality testing practicalities. But I wanted to understand what quality really means in RFID. And why should label converters and tag manufacturers care? Read on to find out what I learned.

Framework of RFID Tag Quality

The quality of RFID tags and labels boils down to RF performance – how consistent is the performance compared to the RFID tag specifications? RF quality cannot be seen with the human eye. Nor can the RF performance of a smart label or inlay be checked with any camera, x-ray, or machine vision. The quality can only be checked with RF (radio frequency) measurement system.

(Note: The other aspect of RFID tag quality, that will not be covered in this post, is tag data content. Learn more about tag data and encoding here: https://landing.voyantic.com/webinar-rain-rfid-encoding-for-barcode-professionals)

With that in mind, the following framework describes the levels of defining smart label RF quality, from design quality to documented production quality control: 

  1. Design Quality means fit-for-purpose
    RFID tags are designed for different use cases and applications. Good quality design means that the tag has the required performance and durability for the intended use case, taking form factor and unit cost into consideration as well. In practice, performance translates into readability and read range of the tag in the environment it was designed for: from how far the tag can be read, and from which angles, what type of items is it a good fit for?
  2. Tags can be functional but not-fit-for-purpose
    Taking a simple approach, the functionality of the tag can be checked with any reader – if the tag ID can be read, it is a functional tag. Sadly, this approach does not reveal aspects of quality, or if the tag meets the requirements or not.

    Consider an analogy to a tag functionality test from the automotive sector: at the end of a car factory line, someone only looks at and listens to the cars: “I see a car and hear the engine – Quality check ok!”
  3. RFID tester verifies that tags meet the specifications 
    A proper quality test measures the RF performance of the tag, preferably on the production line. Voyantic’s Tagsurance 3 RFID production quality control system checks the tags’ performance against pre-set criteria. The system gives a pass/fail result based on the requirements for each RFID tag passing through the system. 
  4. Knowing the production variance is the key to improving your process
    Quality testing also reveals the variance in the tested tags’ performance. The variation in the tags’ sensitivity in practice means the differences in the tags’ read range. Tag sensitivity is the measure of how much power is needed to wake up a tag. Variance is inherent to mass production – manufactured tags are never perfectly identical. Quality requirements set the acceptable variance limits for the tags’ sensitivity, ensuring they meet requirements for consistent performance, i.e., consistent readability of the tags.

    Knowing the variance is essential for internal development: for discovering good practices, and making comparisons – comparing machines, production teams, materials, settings, and so on.
  5. Customers expect proof of quality
    The highest level is to be able to prove the quality in detail. A professional quality control solution automatically records a log of all tests with the tag’s unique codes along the log data. This record can be used to prove the quality of the production batch and to prove the quality of each individual tag.
Testing in RFID inlay and label production is required to verify the produced tags meet the designed sensitivity.

Why Quality Matters…

…for the RFID system end-users?

Variation in sensitivity causes the readability of the tags to vary. Differences in tags’ read ranges lead to missed readings, and ultimately, decreased reliability of the whole RFID system.  High variation in tag sensitivity also indicates variation in durability – some tags may last longer than others. End users will not be happy to see the reliability of the RFID system decrease.

Customers expect consistency and for each tag to perform according to its datasheet information. As customers’ knowledge and experience of RFID technology increases, they also expect a documented quality program and, in some cases, require documented proof of quality from the tag supplier, and even compliance with a quality standard. 

…for manufacturing?

Quality management is the bedrock of RFID inlay and label manufacturing. A complete RFID quality control system gives visibility into the production process to catch production line issues early on before more tags start to fail, thus reducing waste and improving yield. 

The statistical quality data also enables comparing machines, production lines, and shifts. Good practices can be adopted, and poor performance can be addressed, improving the overall efficiency of production.

… for management?

A company’s top management typically focuses on the long-term growth and profitability of the company. High-quality products contribute to customer satisfaction, thus helping to drive more recurring sales revenue. Higher production yields, reduced waste, and increased production efficiency also contribute to better margins.  

The measured quality data is the basis for continuous operational improvements and long-term profitability. In practice, data enables optimizing investments: Which machines and materials work the best, and where there is room for improvement?

The Cost of Bad Quality

As the industrial scale of a company increases, the importance of good quality and reliability gets to a whole new level. Two very typical use cases for RFID are inventory tracking and supply chain management. Big brands and retailers may have hundreds of millions of items tracked and traced with RAIN RFID throughout their supply chain and retailer networks. If you consider, for example, that 1 percent of the RFID tags used to track items do not work well, that doesn’t initially sound too bad. But when you are tracking hundreds of millions of items, 1 percent translates into millions of products being lost from inventory tracking and considered stolen, wasted, or otherwise unaccounted for. 

The Experts in RFID Testing and Quality Control

Voyantic’s core business is to measure the performance of RFID tags and inlays – to help our customers make sure every delivered tag works right, and enable engineers to make better products. Our vision is that every RFID tag and label have been tested and verified in the production process with our quality control system

Get in touch to see if we can help you with your RFID projects!

Learn more:

About the author

21Jesse Tuominen

I joined Voyantic as a partner in 2005 to design Voyantic's first commercial product, and I've had a front-row seat since then to see how the RAIN technology has evolved and matured while bringing my own contribution to it. As a background, I have a MSc level in electronics after which I made my PhD in the field of photonics. UHF RFID slots nicely between these two worlds and they offer a lot of perspective into my work. Currently, as the CTO of RFID technology, I work with new measurement methods, RF design, proofs of concept, standards, protocols, industry collaboration and IPR.

Content

Testing Tags for ETSI EN 302 208

May 05, 2023

We are getting a fair amount of questions on “how to approach ETSI EN 302 208” and I figured I would first give you all the painful details and then summarize what I believe is the right advice. My message is: EN302 208 testing can be made really fast and easy. Read on to find out how!

A bit of history

Right from the early days of the European Union and the UHF band RFID, the “EN 302 208” has been the well-known and unified standard describing how to set up and test RFID equipment to be declared as radio devices in Europe.

The first version was published back in 2004 describing reader requirements, but also briefly touching on the subject of RFID tags by setting a limit for their out-of-band spurious emissions. Most probably this was taken more as input by reader designers to limit Back Link Frequency (BLF) in their ETSI mode, and not really as impacting the work of tag designers. After all, it’s the reader that sets the carrier frequency, and power level and has command over all of the tag’s settings, right?

Well, nine standard versions later we are now at v3.3.1 which has limits for both tag out-of-channel emissions as well as outright limits for backscatter levels both for the ~865 MHz “lower” and ~915 MHz “upper” band ETSI channels. In the last few years, tag manufacturers’ interest to produce and offer labels fulfilling the standard has steadily grown. Most probably as a result of RAIN technology entering new market verticals with longer and stricter traditions of following all kinds of standards.

Feels a bit complicated, why is it so?

The standard has been a tough one for tag manufacturers to decipher as it is written in the form of a traditional EMC standard talking about power spectral densities, transmit masks, and resolution bandwidths.

This makes it harder to compare the limits against more typical RFID tag results that we have gotten accustomed to, such as “power on tag reverse”. However, the greatest layer of fuzziness comes from the fact that the standard is a generic standard, as it understandably needs to be, providing absolutely no help in associating the tests with RAIN technology, GS1 Gen2 protocol, and the equivalent ISO counterpart 18000-63 that 99% of all the UHF tags utilize. This unfortunately leaves a lot of room for interpretation.

The actual test to be performed, according to the standard, sounds relatively straightforward: 1) Radiate the tag by a field strength equivalent to 2W ERP from 20cm away. 2) Record the tag’s modulation spectrum. 3) Compare against limits. Well, a tag doesn’t backscatter anything on its own unless a proper command is given. So, a command is needed in the form of Query, Query+Ack or Query+Ack+ReqRN+Read. For the lower band a BLF of ~300kHz should be targeted and for the upper band ~600kHz. In Gen2, these in practice will often be rounded up to 320kHz and 640kHz as those are the frequencies that all tag ICs can divide their clock down to. The problems arise trying to capture the tag’s response with a spectrum analyzer. The response is always very short, typically only a few hundred microseconds and inconveniently only some 30 µs apart from the immensely more powerful command itself. Accidentally analyze any part of the command or any part of the silence after the tag’s answer and the outcome will be hugely incorrect.

So what is left for interpretation?

According to the standard, the answer should be recorded with a resolution bandwidth of 1kHz around the carrier frequency. This indirectly implies that the answer should be much greater than 1ms for this to be even theoretically possible. So, the exact correct resolution bandwidth can rarely be used except for some high Miller modes in combination with the lower ETSI band’s lower BLF.

This brings us to the perhaps biggest question: Which modulation type and data content should be used in the tests, and is the test supposed to be passed for all of these modes, a typical one, or for any selected single mode of use? The difference in passing or failing the test can be as big as 15 dB between these several modes! In simple terms, a tag that always modulates with a fixed amplitude between the same two impedance states while backscattering will always produce an equal amount of total backscatter power. What is different, is how spectrally spread or focused this power will be. And for the ETSI test, what is recorded in the end, is the strength of the peak spectral feature. So, it will be much easier to pass the test with the power spread across the frequencies as evenly as possible. 

Let’s compare the spectra

The absolute worst case for the ETSI tag emission test will be a “continuous square tone”. That is, a symmetric square wave modulation as in the case of sending a long train of data zeros with FM0 decoding. The same square wave modulation also happens in the miller modes when the extended preamble is requested by the reader. The square-wave backscatter modulation of the tag will create a Fourier-series type of spectrum with almost all of the power concentrating on exactly carrier +/- (n*BLF), where n is an odd integer. This is the absolute most difficult mode to pass the test with and that’s why in the Tagformance system this is referred to as the “worst case” from release version 13.5 onwards. Pass this and you will pass everything else too with no need to test for anything else.

Comparison of spectra of equal power backscatter signals with different coding type and data content.

Ironically, if FM0 is the “worst case” to pass, it is also the “easiest case” when the packet data is randomized. Having a roughly equal distribution of zeroes and ones in random patterns will with high probability create a very spread out spectrum. A spectrum with no predictable high peaks which could breach the mask and fail the test.

Somewhere between the worst and easiest cases fall all the Miller modes producing their tell-tale double-peak “rabbit ear” spectra. Miller modes, ranging from M2 through M4 to M8, are often favored by the readers for their decode sensitivity. This is why we have chosen the M4 with a randomized data packet to be our most “typical case” for tag emission testing.    

The Voyantic way

Currently, Voyantic offers two approaches in the Tagformance system to test for tag emissions. The perhaps more traditional and thorough approach makes use of a separate calibrated Rohde-Schwarz spectrum analyzer which is synchronized to the Tagformance system to record just at the correct moment and for the correct duration to hit the tag answer.

The alternative method is the “simulated spectrum” method, as it is referred to in the Tagformance user interface. Despite its name, it is a tag measurement, where the tag backscatter is measured for amplitude and frequency. The point where a measurement turns into a simulation is when the measured parameters are taken to recreate a prototype of a waveform, the spectrum of which is then evaluated against the mask limits. The simulation assumes a sharp backscatter modulation between two discrete states utilizing a random data packet which is selected to be as average and representative as possible. This is very close to reality, and what is important, is that the reality can only be more forgiving. So, if you pass with the simulation, you will pass in the spectrum analyzer measurement too. The great advantage of a recreated data packet is that it can be created to be of any suitable length and thus analyzed with any resolution bandwidth.

A simulated backscatter spectrum in relation to the ETSI limit in Tagformance. A finer ResBW of 1kHz is used in the central 2MHz according to the standard.

Conclusion

An easy option is to take the EN302 208 testing as a part of the design process as the testing can be made really fast and easy. It is adequate to use the simulated mode as in reality, things are not going to be worse. So if you pass, you pass.

This really means that the measurement system and setup are exactly the same as you would use for tag measurements.

Using Tagformance Pro and a Voyantic measurement cabinet, the result is just a few clicks and a few seconds away at any given time. Simply place the tag on the measurement platform as you would with e.g. threshold or read range measurements and run the tag emission test.

Finally, Just wanted to take this opportunity to mention that our C50 cabinet has a really nice very-low-echoic rotation system, and having a Tagformance Pro and C50 on one’s lab enables truly complete measurement capabilities from basic frequency response (threshold, read range) measurements to EN302 208 and ARC pre-testing. All in one system, easy to buy and use – and to maintain for several years to come.

Ah, one more thing, get the latest version of Tagformance Pro UHF software to have the well-recommended “typical” simulated results at your disposal! No spectrum analyzer? No problem!

About the author

16Juho Partanen

I was privileged to work at Voyantic for more than 20 years mostly focusing on the customers and developing the RAIN ecosystem. While I transferred to the Impinj organization in 2025, I continue the work on the DPP standards at Voyantic.

Content

NRF 2023 Recap – Inventory Management is a Priority and Self-Service Increases

Jan 19, 2023

After two years of idle time I attended the NRF Big Show in New York from 14th to 17th Jan 2023. Three full days of walking was definitely worth the effort. My takeaways from the event are as follows:

Liz Ann Sonders: GEL and demographics

The clarity and reasoning by which Liz Ann Sonders, the Chief Investment Strategist of Charles Schwab & Co., Inc., presented her views on the state of US markets and economy were unprecedented. I made two pages of notes and became her fan. 

Her message in a nutshell as understood by me: the world has exited the era of cheap Goods, cheap Energy and cheap Labour (GEL). That change will also affect the balance of power between capital and labour. For the last 20 years, capital has had the advantage. Going forward, much of the power will transfer to labour.

Factors are numerous, and demographic development is an even stronger force than inflation or the rampart war in Europe. The outcome is that digitalization continues and supply chains will be more carefully managed than ever before.

Outlook of the retail market (Sonders cont.)

While consumer confidence has gone down, the savings rate has been high because of the fiscal stimulus during the pandemic. Due to the accrued excess savings, consumer spending still continues at a high level, but the notable change is the spending baton that is being passed from goods to services.

As a result, many retailers currently carry excessive inventory levels. The industry will work through that, but by now many have learned to be cautious against excess inventory.

Remember this driver (Sonders cont.)

The change in demographics has already shaped many industries in Asia and Europe. Automation and digitalization will increase, due to the increasing struggle to hire and retain the hands that do the manual work. The long-term driver to learn and remember therefore is labour shortage.

Observations from the exhibition floor

I saw more self-service check-out counters being promoted than in prior years. Additionally, the count of robot demonstrations impressed me. Robot applications range from warehouses to shop-floor replenishment, and from inventory scanning to customer service.

The increasing usage of automation obviously makes companies more resilient against labour shortage. It also helps in talent retention, as more time is spent on creative and complex tasks.

Outlook of the RAIN RFID market

(For simplicity, I will discard demand forecasting as it has little to do with RFID.)

Inventory control requires supply chain management, and today’s supply chain management leans on item-level traceability. For technology vendors, the welcome result is that the demand for RAIN RFID technology remains at a high level. What I also heard several label suppliers state is that after a few agonising years, the supply of RAIN RFID tag ICs is getting better. Lastly, I heard the adoption of this technology is finally taking off big time in the logistics industry.

Folks, we are in the right business.

Label-based tagging keeps on increasing

On a high level, several tagging approaches are available: sticker-type labels, hang tags, rugged tags and embedded tags. Labels and hang tags fulfil the scanning requirements of supply chains, and the scalable supplier ecosystem efficiently supports the approach.

I came to estimate that the yearly RFID labels production quantity is already enough to wrap the whole Javitz congress center with RFID labels for its outer surfaces.

At the NRF what I didn’t hear American retailers talk about was product life cycle traceability, digital product passport, and digital twin. They seem to be concepts of the future, which marks a major difference compared to European retailers. I am curious to see if EuroShop presents a different tone.

RFID applications closing in on the US consumers

Millions of American consumers that work in the supply chains already use RAIN RFID every day. At work, they have learned to appreciate the efficiency and convenience that RAIN brings. My question goes: when will they start requesting the same efficiency and convenience in managing their personal inventories and households?

I gather that the world is becoming ready for such a leap as more consumer-friendly RAIN RFID reader products are finally emerging. Sledge-type of readers, that attaches to your smartphone, have been in the market for years already. Recently more slick and  pocket-sized alternatives have been launched, just have a look at the BlueBird VX500 and Unitech RP902. The former is a RAIN-enabled smartphone, and the latter device connects to Android and Apple phones wirelessly.

I believe these products are game-changing as they expand the usage of RAIN RFID well beyond the supply chains and point-of-sale. As the embedded and durable tagging of products increases in the coming years, I am sure consumers find delight and convenience in RFID also outside of their working hours. 

Passive Bluetooth 

Wiliot was already a familiar name from several prior industry events. Wiliot is an IOT platform that connects BLE-based sensors, “IoT Pixels” as Wiliot calls them. The sensors carry an ID and sensing capabilities. The sensors don’t require a battery, instead, they harvest energy from nearby transmitters, which makes them relatively cheap and small, practically stickers. Additional gateways pass the encrypted sensor data to the cloud.

The difference to RAIN in Wiliot is that the IoT Pixel data can only be accessed via cloud. Wiliot runs a SaaS business. The Bluetooth infrastructure and consumables are relatively cheap, and a Wiliot system is easy to set up.

Three additional findings from the exhibition floor are worth mentioning:

  1. Another company Nexite also utilizes BLE technology and follows a similar SaaS business model
  2. There is an emerging paper-thin ecosystem of suppliers that produce Wiliot labels. 
  3. I came across a Wiliot-enabled prototype printer.

In my assessment, passive Bluetooth is in its infancy the same way as RAIN RFID was 20 years ago. Technology itself is demonstrated to work, although practically the sensors cannot yet be read with smartphones. All in all, I remain curious to see how passive Bluetooth takes off.

Final thoughts

The NRF Big Show is overwhelming in its size and range of content. After three days at the exhibition and conference, I was left with a warm comforting view that the growth of the RAIN RFID market is set to accelerate. It is a very exciting business to be in. 

About the author

16Juho Partanen

I was privileged to work at Voyantic for more than 20 years mostly focusing on the customers and developing the RAIN ecosystem. While I transferred to the Impinj organization in 2025, I continue the work on the DPP standards at Voyantic.

Content

Upper European RAIN RFID Frequency Band Increases Adoption

Nov 10, 2022

How cool is NFC in that it simply works all over the globe: 13,56 MHz everywhere? How cool do you think it is, that RAIN RFID today enjoys the same: several reader channels between 902 and 928 MHz on all the continents!

Status up until 2018: two regulatory regions with no overlap

Traditionally, the end users and RAIN solution providers have accepted and adapted the fact, that in Europe RAIN deployments have been limited to operate at the 866-868 MHz range, also known as the ETSI range, where the four reader transmit channels are. The rest of the world utilized reader transmit channels somewhere between 902 and 928 MHz – the so-called FCC range.

The EU decided to harmonize the RAIN RFID band in 2018

After years of CEPT (short for European Conference of Postal and Telecommunications Administrations) technical studies and mounting pressure from the RAIN end users, the Commission Implementing Decision (EU) 2018/1538 specified three reader channels at 916,3 MHz, 917,5 MHz, and 918,7 MHz. The Commission also defined the implementation deadline as 1st February 2019 but acknowledged several exceptions for existing regional radio systems, such as military and railway deployments.

The picture above shows how well the European new RAIN RFID reader channels fit among the other global regulatory regions.

Status today: 902-928 MHz covered by a grand majority of countries!

As we study the RAIN RFID regulatory status document maintained by Mr. Craig Alan Repec of GS1 Global Office, out of the listed 81 countries with known status, 55 offer RAIN RFID reader channels between the band 902 – 928 MHz. Out of the CEPT 46 member counties, 25 have partial or full implementation for the upper European RAIN RFID channels, and that number is rising every year.

Performance benefits are significant

As one looks behind the numbers, you come to realize that specifically, the upper European band is wonderful news: more of everything! 

Comparison of lower and upper European RAIN RFID frequency channels

“The upper European frequency band definitely offers dramatically more wiggle room for RAIN engineers to optimize system and component designs,” says Dr. Jesse Tuominen, the CTO RFID of Voyantic.

Business benefits 

As most supply chains are global, it makes sense to keep the RAIN tagging specs at 860 – 930 MHz. This way tagging is responsive all around the globe, which adds simplicity to the deployments.

In certain applications, it might even make sense to narrow down the tagging specs to 902-928 MHz, as tagging and reader antennas can be further optimized for performance, footprint and, ultimately, cost. I believe this opportunity is especially interesting in applications, where there are severe space or area constraints for either the readers or the tagging.

What’s up with the slow adopters

Well, all I can say is that the RAIN RFID end users in Germany, the Netherlands, Croatia, Greece and a few other countries are in a totally unfair situation – they are outliers that remain limited to the lower European RAIN frequency bands for the time being.

For future-proofing RAIN RFID deployments also in Germany, please prepare to upgrade systems to support the Upper ETSI frequency band.

Having said that, I foresee that nuisance to eventually pass. My advice is to prepare to upgrade deployments as those reader channels become available later on. Practically that means requiring the deployments to be compatible with and upgradeable to the 915-917 MHz in the RAIN project specifications.

Bottom line: use the upper European reader channels and be appreciative of them!

The awareness around the global harmonized RAIN frequency band has been slim. However, numerous end users are embracing it. “Most of the main RAIN users in France have declared they are going to use the upper bandwidth for their deployment to get all benefits from this new frequency possibility”, says Hervé d´Halluin, Leader RFID & Traceability of Decathlon. “This represents tens of thousand of locations spread all over France.”

What about the appreciation? Regulatory advocacy is an area where industry stakeholders need to pull their ranks together. With the help of industrial associations, such as the RAIN Alliance, AIM and GS1, we’ve done just that. If you’re in the RAIN RFID business for the long run, make sure your company supports these associations by becoming their member, because regulatory work never ends.

About the author

40Toni Ala-Piirto

I am the CTO for software development at Voyantic. I have twenty years of software development experience, ranging from small to large-scale projects in a variety of roles. I'm a hands-on person striving for constant improvement, for myself as well as for the people whom I closely work with.

Content

Life of Voyanticians – The Lazy Engineer

Oct 13, 2022

Content Warning! This post includes some serious engineering terminology. Reader discretion is advised! 😉

“Being Lazy”

At Voyantic we value “lazy engineers”, a term that often is linked to efficiency in the engineering context. One key aspect of efficiency in software development is automation, and software engineers have been working with CI (continuous integration) / CD (continuous delivery) systems for eons to have their code automatically built, tested, and deployed. Typically these CI systems run neatly on the cloud, either self-hosted or as a service.

The same CI / CD practices are not nearly as widely adopted on the embedded side as those are on the server-side software. This was also true for Voyantic, but we have decided that there are no excuses not to have HW part of the CI cycle, especially when the other option is to do manual regression testing – ouch!

In this blog post, I’ll describe how we try to be lazy while leveraging automation in our development and testing practices.

Efficient Test Automation

4 Key aspects for efficient test automation

  1. Test triangle as a guideline
  2. Automate everything
  3. Fast feedback loop for development
  4. Reliable tests and automation

How these are applied at Voyantic

For those unfamiliar with the test triangle, it is best depicted by the following diagram.

Lower-level tests are running faster and have the opportunity to test corner cases more easily but are run in isolation, without testing the interoperability of the code and components. Capability for rapid code changes requires fast test cycles. Pull request (PR) builds are running unit tests and integration tests to have that fast feedback cycle, typically within minutes, and covering both the fine-grained unit tests and integration tests ensuring interoperability.

Unit test definition always seems so clear until you realize that developers have vastly different unit sizes that they test. Our approach is to test code in isolation, one file/module/class at a time, and mock anything external. Truly testing just the unit.

At the integration test level, we prefer the real thing over mocks. Firmware changes are flashed to the device and tested using its API and cloud services are deployed and tested using their API. If a tested piece of a component depends on other services or hardware, then real hardware or deployed service is used instead of the mock. In some cases, it is not possible to avoid mocking or simulation but those are the exceptions that make the rule. Mocking is avoided for a couple of different reasons; 1. There is a significant amount of development and maintenance required to mock something. 2. Mock always fails to simulate the real thing perfectly, allowing bugs to go unnoticed.

End to End tests are gating software release and performed on a high level, simulating the end-user behavior, potentially having a long execution time. For example, we are using Playwright to test ReactJS-based Web UIs. This category includes also other long-running test types, like soak tests, where for example our Tagsurance 3 system is run for days without interruption to simulate its usage on the production line producing RFID tags. These types of tests will catch issues that only manifest over time, like a slow memory leak, data store efficiency with bigger data sets, overheating, etc. 

Theory Meets the Hardware

The above diagram depicts the high level CI-system architecture. Jenkins leader is running on a dedicated AWS CI account. The leader is starting on-demand Jenkins followers for build jobs not requiring access to the Voyantic hardware devices. Build jobs using Voyantic hardware devices are run on the on-premise Jenkins follower. This gives us the ability to test cloud services efficiently with co-located cloud-based followers, as well as embedded software running on our own HW devices connected to our on-premise servers.

All continuous integration pipelines are fully automated. Once the developer creates a PR, it will start the Jenkins pipeline to build the code, run static checks and unit tests, deploy it to its target environment, and run integration tests. After merging the PR to the main branch, the pipeline is started again and the same tests are executed but in addition, E2E tests are run too. 

Not to be overly rosy in this description, this does not apply to all of our git repositories and some are lacking direly behind but all new software is following this model and we are relentlessly working to add all other SW components under active development to this model.

The last key aspect of test automation is reliability. Regular failures due to badly designed tests will cause failing test jobs to be ignored, leading to gradual test deterioration. This matters a great deal, especially on the e2e test phase – since e2e tests are not gating the PR merging to the main line, it makes it easier for developers to ignore. Rather test less and more reliably, than have complex brittle tests.

Summary

After reading the above “Wikipedia” page of the testing and falling asleep, here are a few key points to take home.

  • Use the test pyramid as a guideline to define and understand your test levels on CI
  • Aim to have a fast feedback cycle
  • Simple reliable tests over complex but brittle ones
  • Provide infrastructure to support the continuous integration with your own devices
  • Be “lazy” and automate all repetitive tasks