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Jul 26, 2022

Best Practices for RAIN RFID Label Quality Testing

RAIN RFID, aka UHF RFID aka EPC RFID, is the technology used in connecting billions of everyday items to the Internet. In 2020 RAIN RFID tag volumes exceeded 21 billion, and in 2021 volumes reached over 28 billion. We are seeing this strong growth continue. As a result, huge amounts of new production capacity will be needed, which means that 

  • more machines are needed,
  • single-lane machines need to be converted into multilane machines, and
  • machine lane speeds must be increased.

At the same time, RAIN RFID users have started to pay more attention to their RFID label quality.

In this article, I will share Voyantic’s experiences and views on RAIN RFID quality testing:

  • What is essential in planning quality testing in RAIN RFID label manufacturing?
  • What are the current best practices in RFID quality testing?

What does good manufacturing quality mean for RAIN RFID tags?

At the very basic level, the good manufacturing quality of RAIN RFID tags could be defined as: “Manufactured RAIN RFID tags are not defective.” This definition is easily understandable, but it does not offer much practical help. In fact, it is misleading.  Sometimes “not defective” is interpreted as “can be read”, and that leads to problems. When RAIN tags start to break, their read range gradually decreases and, only at the very end, the tags become entirely unreadable. 

A better definition of good RAIN RFID manufacturing quality is: “Manufactured RAIN RFID tags’ sensitivities are within set variation limits”. This definition is a bit more technical, but let’s break it down:

  • Tag sensitivity describes how much power is needed for waking up a tag. Tag sensitivity is at the background of all practical performance features. For example, if a tag’s read range has changed, also its sensitivity has changed. If a tag’s orientation pattern (read range in different angles) has changed, also the sensitivity has changed. If a tag’s response strength (backscatter) has changed, the sensitivity has also changed. Shortly – any change in a tag’s performance can be seen as a change in the tag’s sensitivity. Or the other way around – if the sensitivities of two individual tags of a model are the same, they will perform similarly in every way.
  • Variation refers to consistency. Tag designs are different. Some tags are designed to have lower sensitivity (shorter read range) than others. The consistency of the performance within a tag model is important for the users. 
  • Within set limits implies that there are limits, but offers some freedom for setting the criteria. Some applications require exact read ranges – an item moving past a reader on a conveyer belt may require read ranges within some centimeters. Shorter range causes missed reads, and a longer range would risk stray readings – reading unwanted items that are not on the belt but nearby. Some applications have a higher tolerance, and a read range variation of a couple of meters may not be a problem.

RAIN RFID manufacturing quality is good when “Manufactured RAIN RFID tags’ sensitivities are within set variation limits”. This definition also works from a practical point of view.

What does the RF performance of RAIN RFID tags mean?

From a practical point of view, the RF performance of a RAIN RFID tag defines 

  • how far the tag is readable
  • at different angles
  • when the tag is attached to an item.

In tag datasheets, these are commonly described with graphs.

  • An orientation pattern shows how well a tag can be read when it points to a reader from different angles.
  • A threshold curve shows the tag sensitivity – how much power is needed to wake up the tag at different frequencies. A version of the threshold curve may show read range instead of power. 
Picture: Threshold sweep and orientation graphs from Tageos EOS-500 datasheet

Good quality manufacturing produces tags that have consistently similar orientation patterns and threshold curves. The good news for manufacturers is that full measurement is not needed to check that the tags are similar to each other. In fact, this can be checked with minimal test procedures.

How should RAIN RFID tag quality be tested in manufacturing?

It should be kept in mind that one method does not fit everyone. However, RAIN RFID industry seems to be converging towards the following methodology. 

These are the current best practices:

  1. Far-field performance of the tag is tested
  2. Test recipe that separates good and bad tags efficiently
  3. Cross reading is reliably prevented

These best practices may seem simple and obvious, but there are details to consider. Let’s look at these key points in detail.

1. Far-field performance of the tag is tested

In production machines tags are close to each other. Close proximity reading is needed for preventing cross-reading, and for practical reasons. At the same time, a quality test needs to address the far-field performance of the tag. A common near-field antenna cannot be used. Voyantic has solved this close proximity vs. far-field conflict with the patented Snoop Pro antenna concept. This unique antenna requires the tag to use its far-field properties in close proximity.

2. Test recipe that separates good and bad tags efficiently

Separating good and bad tags is an obvious requirement. But how to do it efficiently, at production speeds, when tags fly over the antenna at high speeds? A current best practice test recipe is often referred to as the “three-point test” or “3-point test”. The three-point test recipe includes 

  • testing the tag at three different frequencies across a wide frequency band (hence the 3-point test name)
  • checking that the tag sensitivities are within 3 dB from each other (+/- 1.5 dB)
  • checking that the tag’s EPC code can be inventoried

This is how the test recipe is created:

  • A good starting point is to set test frequencies to 820 MHz, 950 MHz, and 1080 Mhz
  • Adjust one of the points to match the tags’ lower resonance frequency
  • If possible, adjust another frequency to match with the tags’ upper resonance frequency. 
  • select third frequency so that the frequency spread is at least 100 MHz
  • at least one of the points should be an inventory test (for reading EPC)
  • at least one of the frequencies should be a sensitivity test, with 3dB between upper and lower limits
  • the power level for the points should be set so that tag sensitivity in each point is within 3 dB, or +/- 1.5 dB 

Considering the recipe, this 3-point test could be described as the current industry best practice.

Picture: 3-point test recipe as seen in the Tagsurance recipe builder

In the sample tag (above graph)  both resonance frequencies (868 MHz and 995 MHz) are in the available frequency range. The sensitivity test is set to the lower resonance frequency and the point test is set to the upper resonance frequency. Because the frequency spread is over 100 MHz, the third frequency is set in between. An inventory test is set to this frequency. 

In the above picture, the curve is a median performance tag’s threshold sensitivity curve (reference).

Shows sensitivity test frequency and power range, in addition, a 3 dB range is set for the acceptance criteria. the frequency is set to the lower resonance frequency.

Shows the point test frequency and power. The power level is set 1.5 dB above the threshold of a median performance tag.

Shows the Inventory test frequency and power (for reading EPC/UII code).

3. Prevent cross-reading

Cross-reading occurs when one tag is thought to be read, but in fact, data comes from another, nearby tag.

In normal use, RAIN RFID tags are inventoried. They are read with a speed of more than a hundred tags per second. Testing production quality is different. Tags are tested one at a time, and it is critical to be sure that the results are from the right tag, even if another tag is just millimeters away. And to add to the complexity, all has to happen while the tags move at high speeds across the antenna. 

Voyantic’s Snoop Pro antenna concept includes a method for completely preventing cross-readings. The antenna concept includes a shielding plate with dimensions matched to the inlay’s antenna and repeat length dimensions. This solution assures that cross-readings do not occur.

In addition to the above comments, 2 more notes can be added from the manufacturing point of view.

4. Speed

Production is about the combination of speed, capacity, and quality. Quality testing UHF RFID tags should not be the bottleneck for production. If any machine output needs to be limited because of quality testing, this would add to the cost of quality.

Voyantic Tagsurance 3 system is designed for high-speed production lines, for continuous production use. 

5. Automation

RAIN RFID tags are manufactured in volumes in different machines. Production runs are in millions, and any sample testing is not possible in practice. A common requirement is that tags of unknown quality are not accepted, this forces testing to cover 100% of the manufactured tags. 

The testing must be automated and integrated into the manufacturing machine. 

Voyantic Tagsurance 3 system can be easily integrated into any machine. 

Are there quality standards or specifications to follow? What about quality certifications?

Common quality standards and practices such as ISO9000 series standards and six sigma can be applied to RAIN RFID. However, these standards do not offer practical advice on acceptable quality limits. 

Exact quality limits have emerged within the RAIN RFID industry. The above-mentioned three-point test and tag sensitivity variation within 3dB is a commonly accepted good practice.

ARC RFID lab is offering quality certification for UHF RFID / RAIN RFID inlay manufacturers as a part of their tag certification program. Correctly implemented three-point test using Voyantic Tagsurace system meets these requirements.

The 3dB variation and three-point testing cannot be used every time – adjustments may be needed. The quality requirements arise from the RAIN RFID / UHF RFID users’ consistency requirements. If an RFID user needs very tight read range tolerances, a smaller variation limit may be needed, and in some cases, wider tolerances may be perfect for the customer. 

Learn more about the Tagsurance 3 System

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On-Demand Webinar: Introducing Tagsurance 3

Tagsurance 3 is designed to meet the requirements of the increased RAIN RFID industry’s tag production capacity and the higher demands for quality testing in tag production.

Watch the Tagsurance 3 product demonstration webinar to see the system in action.

Jun 28, 2022

Voyantic Releases Tagsurance® 3 – The Next-Generation Quality Testing Solution for RAIN RFID and NFC Manufacturing

Tagsurance 3 Brings Accurate High-Speed Inline Testing into UHF and HF Tag Production to Meet the Growing Needs of the RFID Industry

Today Voyantic is releasing the next-generation solution for RAIN RFID and NFC tag production testing and quality control. Voyantic Tagsurance 3 system brings full visibility into the quality of tags in the production line, ensuring tags meet the designed performance features, without slowing down the production process. The Tagsurance 3 System allows, for example, three-point testing at high speeds, with accurate measurement results.

Tagsurance 3 is a complete solution including the Tagsurance Controller rack for triggering, sequencing, REST API, and operator UI, as well as measurement devices, antennas, cabling, trigger, and rotary encoder. The Tagsurance 3 Controller is ready to be used out-of-the-box. The operator UI is browser-based and easy to use.

The system is designed to be easily installed into various machine types; small and large machines, high-speed machines, chip attachment machines, and converting machines. The system is modular and scales to various production volume needs from 1 to 8 lanes with 1-5 stations per lane, handling lane speeds up to 200 meters per minute.

The new Tagsurance system is the next-generation version of the time-tested, trusted, and accurate quality testing system Voyantic introduced to the industry. In the new system, the hardware, the software, and the technology stack have been upgraded and modernized.

The first version of Tagsurance brought UHF quality testing into tag manufacturing machines. Tagsurance 2 expanded the capabilities into HF quality testing.

“The new Tagsurance 3 is designed to meet the growing demands of the RFID industry. The new system can in many cases handle around twice the speeds for RAIN testing than before, without compromising measurement accuracy. Our goal is to deliver the best performance and make sure the system works reliably for our customers,” says Jussi Nykänen, Director of Production Solutions at Voyantic.

Learn more about the new Tagsurance 3 System ›

Introducing Tagsurance 3 – The Next-Generation Quality Assurance Solution for High-Speed RFID Tag Production Lines

Date & Time:
Thursday, July 7, 2022
2 pm EEST / 1 pm CEST

Join the Tagsurance 3 product demonstration webinar to learn all about the new system.

Feb 01, 2022

Webinar Series for Barcode Pros – Getting Started with RFID Labels

Last year, we teamed up with TSC Printronix Auto ID and started a webinar series designed for barcode professionals, who are considering expanding their offering to RAIN RFID labels, or who already are at the beginning of that journey. With TSC Printronix Auto ID we saw the need for education as more and more barcode label customers are looking for RFID solutions. 

In the first webinar, What a barcode professional needs to know about RAIN RFID Label and Tag Data, we started from the basics: what are the key aspects of RAIN RFID technology and data, how does RAIN RFID actually work, what are the system components, and most importantly, where can you find more information. 

The second part of the webinar series, What a Barcode Professional Needs to Know about the RAIN RFID Encoding Processes, focused on the practicalities of the RAIN RFID encoding process, equipment, and alternatives. 

In the third webinar, What a Barcode professional needs to know about RAIN RFID label selection and sourcing, scheduled for February 10th, we will cover the most important considerations related to label selection and sourcing process including label specifications, supplier selection, delivery format, handling, and other issues.

Here are my main takeaways from the first two webinars in the series.

Key Takeaways from Part 1 

It is crucial to understand filtering in the context of RFID systems

The nature of RF signals means that they can go through walls and various other materials. A RAIN RFID reader can read a large number of tags simultaneously and without a line of sight, which is, in comparison, required for reading barcodes. For example, when you are inventorying tagged items in storage, your system could be reading tags behind a wall that should not be included in your inventory. Setting up tag filtering correctly ensures that your application works accurately, and that requires following proper data encoding processes. 

There are 9 RFID tags on the wall, but the reader found 54 tags.

There is no “one size fits for all” RAIN tag

What do you need to know about RAIN RFID tags when looking for a tag for your customer? The difference between a barcode label and an RFID label is that the RFID label includes an IC (microchip) and an antenna. Together the IC and the antenna make up an RFID inlay. There are lots of different IC models out there and the type of IC defines what kind of and how much data can be encoded in the tag. The antenna model defines how far the label can be read. Knowing your solution requirements, physical factors such as the label size and item materials, and use cases and data requirements are necessary for finding the best tag for your solution.

Do not use a proprietary numbering system

Keeping the importance of filtering in mind, it is crucial to understand the basics of RAIN RFID encoding systems, i.e., how you are putting data into a tag. There are three data standard families available for RAIN RFID tag encoding

Following one of the established data standards ensures there won’t be issues with tag filtering (and application errors) along the road.

The fourth option is to use your own proprietary encoding systems – Please do not do it! Or if you do, you need to “wrap” your system within the ISO standard or the RAIN numbering system.

Selecting the data standard to use often depends on your customer or the industry you are operating in. Some customers may mandate that you use a specific standard, and many industries have a mandated or de-facto standard in use to ensure interoperability.

Above are my key learnings of Part 1, but many more topics and details were discussed. Watch the webinar to learn more about each of the data standard families, including the structure of the different numbering systems and example use cases, as well as the basics of data security. Webinar part two dives deeper into the standard selection process and the specific advantages of the different standards.

Key Takeaways from Part 2

Label Manufacturing Process

The label manufacturing process includes three steps. In the first step, the IC is attached to the antenna, creating an inlay. In the second step, the inlays are converted in a common backing material called a liner, creating a blank label. In the third step, data is printed on and encoded into the label, creating a finished label.

While the process itself is simple, the manufacturing machines are quite complex. Watch the webinar to learn more ›

Encoding Equipment Types and Process

The suitable type of encoding equipment depends on the volume of tags that need to be encoded. The more sophisticated machines that can process high volumes at high speed naturally come with a higher cost.

An RFID reader can be used as an encoder but it is not an efficient permanent solution.

An RFID printer is purpose-built for encoding and is best suitable for small rolls and batches. They can be affordable and process up to some thousands of labels per hour.

High throughput personalization machines can take in larger rolls and process up to one hundred thousand tags per hour, but they also come with a higher cost.

And finally, encoding can also be integrated into product production or packaging lines.

Watch the webinar recording to dive deeper into the IC selection factors, encoding process steps, RAIN tag memory details, as well as tag locking and passwords – ensuring the right data is encoded in the right way.

The Personalization Process

The personalization process includes both printing data on the label and encoding the tags. The printed data can be the same data that’s in the RFID tag or include additional information. 

High throughput personalization lines often process labels in successive stations. Combining the print and encoding in a high-speed personalization process requires accurate triggering for all the steps and making sure the stations match the process flow.

An example of personalization stations in a high throughput personalization process.

Using an RFID printer for personalization is a good option for smaller-scale projects. An RFID printer prints the barcode and other designed details on the label as well as encodes and verifies the RAIN tag data.

Part 3: RAIN RFID Tag Selection and Sourcing

Learn the most important aspects of label selection and sourcing, including label specifications, supplier selection, and delivery format.

Oct 28, 2021

RAIN RFID on Label Processing Machines: An Overview to Help with Your Choices

Traditional label producers entering the RAIN RFID business are faced with strategic and practical questions:

In this third blog of the series created with NXP® Semiconductors, we specifically address production machinery. Read on to learn about the machine types, what approaches to consider, and how to avoid pitfalls that would cost you time, money, and nerves.

Yes, There Is a Growing Market!

RAIN RFID adoption is growing at an unprecedented rate; with those markets that have already seen the benefits of the technology, such as retail and automotive, continuing their adoption. Other markets are emerging, for example parcel services, which is driven by the e-commerce boom.

Majority of these applications are based on RAIN enabled labels being added to the item. If you are already supplying labels to consumable products, the day will come when your customer asks you to add the RAIN labels on your supply program.

It Is Easy to Get Started with Outsourced Inlays

If you already have the ability to produce labels, adding RAIN RFID inlay on the backside of your current products would be one easy way to get started. You will need a capable inlay vendor, and you will need to teach the basics of RAIN RFID to your sales and production staff. Investments required to upgrade your current machines are modest, and inlay vendors are easy to find.

As you learn and build your customer base, it is possible later to expand your business also to cover the inlay part. At that point you will likely need to do a few new hires for development and production, as well as make investments on new machinery – the stakes become higher.

Manufacturing Process is No Magic

The manufacturing process of smart labels follows quite a standardized flow, as in the picture below. While some companies cover most of the process steps in-house, other manufacturers have assumed a more networked business model. Traceability across processes is a tremendous asset for failure root cause analysis, which is one cornerstone for enabling continuous improvement in any organization.

The three essential machine types that you should become familiar with are presented in the next picture:

Let’s understand these machine types and some of the related choices.

The IC Attach Machine Is Where the Inlay Quality is Achieved

The main technologies are flip-chip, and direct die attach. The RAIN IC placement on the dipole antenna requires high precision. Precision, combined with high line speed and sophisticated mount pressure control, makes the IC placement head the most expensive subassembly of the whole machine. You should make sure that the placement head is compatible with current and future RAIN IC’s.

As you look at the machines, you will quickly realize that the number of lanes in the machines varies. Multilane machines typically have higher throughput than single-lane machines, at the expense of added machine complexity. On the positive side, a multilane machine does not need that high line speed to reach an impressive throughput, which may lead to a more straightforward technical construction on the IC placement head. If you’re focusing on bulk, go with a multilane system.

A single lane IC attach machine is less complicated and thus easier to operate. It’s also easier to configure for new antenna models, making it better suited for smaller production runs. The capital investment is also lower.

Three Topologies of Converting Machines

In label converting, different material layers are added on top or under the inlay. There may also be cutting and testing involved. Converting machinery is more versatile, but three separate machine families can be found:

You can have a single lane machine that runs in a continuous mode very fast. Alternatively, you have a multilane machine running slower, and even in intermittent mode. At the end of such a machine, you may have a cutting and slitting module to separate single reels from a web.

A third approach, especially for traditional label suppliers, is to start with an industrial press, and add an inlay insertion section on the machine. An outcome is a multilane machine running in continuous mode.

Personalization Makes Labels Unique

Personalization focuses on getting the data right. Data on the tag is stored both in optical and electrical forms. Therefore, most personalization machines handle both printing and RFID encoding.

While that may sound trivial, managing the data, performing all the needed data conversions correctly, and keeping all the process peripherals in sync is easier said than done. When process speed increases, you will need to pay more attention to details, such as triggering. When working with variable data, you should make sure the optical markings match the unique identifier encoded in the RAIN IC.

Got Machines Already? Consider a Retrofit

It is often possible to retrofit the needed RAIN RFID peripherals on an existing production machine. With a low capital expenditure and a short lead time you’re able to pursue your first RAIN projects.

Voyantic delivers solutions to control sub processes, manage the data between the processes and keep both data and sub processes in sync. We also offer transferable bolt-on alternatives. Such frames come complete with the needed sensors, cabling and antennas, and won’t require changes on the signaling of your current machine.

You don’t need to figure all these details out. Let our experts talk with your machine vendor, and come up with a proposal!

Contact us

On-Demand Webinar:

Quality Management Approaches in RAIN RFID and NFC Manufacturing

Hear industry experts share their experiences in RFID tag manufacturing and quality management. The webinar includes case examples and presentations on how to set quality goals, which standards are relevant, and best practices for quality testing — from setting up the quality program to managing the day-to-day activities.

Watch now

Aug 18, 2021

Smart Label Durability – Bring Facts to the Table

When there is a need to increase smart label production volumes, it can be done by adding new machinery, more lanes to existing machinery, or by increasing production speeds. All these methods are in use, and they are combined frequently. For example, new production machines have more lanes and higher lane speeds.

At Voyantic, we are seeing that increasing lane speeds combined with smart label component development has put durability testing into the spotlight. In this article, I analyze the reasons behind the increased interest in smart label durability testing, and I will share the basics of the test methodology.

Why is the interest in durability testing increasing?

I believe that part of the increased interest can be seen as a healthy sign of technology maturation and market growth. RAIN RFID and NFC just work. Technology suppliers do not have to fight with the basic functionality and the focus is shifting to scalability. Outside of some special use cases, durability has been taken as given.

Let’s have a look at the drivers that are now challenging label durability.

Decreasing IC sizes

The latest generation of RAIN tag ICs is becoming smaller. When ICs are getting smaller, a natural question is what happens to the connection between the IC, the antenna, and the liner. And what is the effect on the inlay durability?

The latest generation of RAIN tag ICs is becoming smaller

The transition from plastic to paper-based labels

Due to ecological aspects, paper is used increasingly as label base material. The “stickiness” of antennas and ICs to paper is different compared to a plastic liner. Paper also stretches and bends differently than PET.

All paper is not just paper, but different additives and fillers are used to create different properties. All these properties, whiteness, polishing, and so on, may affect how the antenna and IC stick to the paper. Finally, add humidity as an environmental variable, and the durability of the paper-based label needs to be studied for sure.

Faster IC attach processes and new bonding epoxies

IC attach machine speeds keep on increasing and the machine vendors are working their way towards 100,000 UPH. The stress to an inlay with a freshly attached IC is higher when lane speeds increase. There is also less time to cure the bonding glues, which has led to new glues being introduced. These new glues require less time to cure, but may need higher curing temperatures. Again, a question about durability comes up: How to fine-tune the bonding process so that the label durability is not compromised?

Faster converting machines

Converting process speeds are also increasing. Higher machine speeds stress the inlays and labels. An obvious worst-case to avoid would be inlays starting to break already during the converting process. Do the inlays survive intact through these fast processes?

Label type NFC tags

Traditionally a label has been one of the major RAIN RFID tag formats. NFC tags have been made more as smart cards, various key fobs, and other more rigid formats. Lately, NFC label production has also started to grow. This extends the label durability question from RAIN RFID to also NFC. Are NFC labels also durable enough to survive through the label life cycle?

All the above changes are happening in parallel. The combined outcome is what matters. Are the inlays durable with all the new materials, components, and processes?

Standard durability test method

Test principles

The basic principle of durability testing is to compare a meaningful parameter before and after a stress, and to analyze the results to determine whether the stress creates unwanted consequences. Because the tags under testing are stressed, potentially to the point of breaking them, the method cannot be used for testing every individual tag. It is rather used to test the designs, and indirectly the manufacturing processes.

For many electronics products, heat cycling is a standard durability test method. Also, drop tests, pressure tests, tumble tests, and shear tests are frequently used. For smart labels, the default test method is bend testing. The need for bend testing comes from the typical smart label failure methods.

The two most likely points to fail in smart labels are chip bonding and the edges of the IC. Bend testing is a way to verify the sufficient durability of both of these possible failure points.

Test method

At the beginning of the test, a baseline performance needs to be measured. The baseline performance of the sample set consists of the threshold sweep result of each of the tags in the sample. The threshold sweeps can be done with Voyantic Tagsurance® devices. The curves describe how much power is needed for waking up the tags at different frequencies.

Threshold sweeps of 98 pieces of RAIN RFID inlays before the durability testing

After the baseline test, stress is applied to the tags, and then the tag performance is tested again.

This cycle of test rounds and stressing the labels are repeated until a targeted performance decrease has been reached. The more test rounds an inlay (label) survives, the better is the durability test result aka durability rating.

Threshold sweeps of 98 pieces of RAIN RFID inlays after several rounds of stressing

The test method document describes the details of the test parameters and stress parameters.

Download the detailed standard test method description

Special tags

There are some special tags where bend testing is not (the only) relevant durability test method. For example, aerospace tags are tested according to the SAE AS5678 standard, which defines environmental conditions such as temperatures, vibration, etc., which the tag must sustain. With these standards, the tag is stressed with vibration and extreme temperatures instead of the typical bend testing, which is designed to highlight the common failure methods of cracked bonding and cracked ICs.

The same test principles can also be combined with other durability testing methods. For example, laundry tags could be tested using ISO15797 standard, which defines how garments are stressed with washing cycles. The idea is the same: to find out whether the tag performance decreases too much when stress is applied.

Also, specialty tags that are intended to be used in extreme conditions, exposed to heat, cold, or chemicals, should be tested in combination with applicable stress methods. IEC60068-2 standards (environmental testing of electronics products) provide help for these. IEC60068-2-2 (dry heat) and IEC60068-2-14 (temperature variation) are likely useful methods, and both can be combined with Tagsurance testing. The IEC60068 family also includes test methods for different mechanical stress types, chemicals, humidity, and so on.

In these special tag durability tests the RFID testing, both baseline and the test after stress, can be made with Tagsurance® systems. Between the RF tests, different stress is applied with the Voyantic Bendurance machine.

Voyantic Bendurance™

How durable is good?

An obvious question related to durability testing is: How durable is durable enough? Or: How durable is good and what is not good enough?

There is no clear answer to these excellent questions. Laundry standard ISO15797 has its criteria and a way to define what is durable enough. SAE AS5678 similarly has its criteria for aerospace tags. But those criteria cannot be extended to other use cases and tag types.

One answer could be: Durable enough is when a smart label survives its intended life cycle. That answer does not help in practice.

Another way is to look at comparison data. It doesn’t give a simple answer but probably helps in practice. If an inlay is as durable as others, most likely it is durable enough. And on the other hand, if an inlay is less durable than a typical inlay, a closer look should be taken, and possibly an improvement is needed.

Comparison data in mind we tested some dry inlays with the following results.

Change of dry inlay yield after each test round

There were significant differences in the dry inlay durability. With the weakest dry inlay model, over 90 % of the inlays broke beyond specified performance with the first test round. The strongest inlays survived more than 10 stress rounds.

  • About 20 % of the dry inlays got a durability rating of 1-3
  • About 60 % of the dry inlays got a durability rating of 4-9
  • And about 20 % of the dry inlays got a durability rating of 10 or higher
  • Median durability rate for all the tested dry inlays was 4, and average about 5.5

This suggests that dry inlay durability could be considered typical if the durability rating is between 4 and 9.


Faster manufacturing machines and new materials have increased the need for testing the durability of RAIN RFID and NFC inlays.

Voyantic Bendurance is a durability test system focusing on bending, the typical failure mechanism of the inlays. Bendurance with its standard test method gives comparable durability data of the inlays.

A similar approach can also be used with other durability testing such as the SAE AS5678 test for aerospace tags, ISO15797 tests for laundry tags and tags integrated into apparel, and IEC60068-2 for durability against extreme temperatures, other types of mechanical stress, chemicals, and so on.

Download the standard test method description

Request a Bendurance demo

Request a durability test system quotation

May 03, 2021

Analysis of the Cost of RFID Quality – And How (Not) to Lose a Customer

We hosted a webinar on managing quality in RAIN RFID and NFC manufacturing. During the session, industry experts shared their views on setting quality goals, on the relevant standards, and on best practices for quality testing through case examples and practical tips. While veterans in RFID quality testing recognize the need for it to achieve excellent and consistent quality, for many less experienced in the field, it can be puzzling to justify the investment for the required RFID test equipment.

With this in mind, it is worthwhile to explore whether the cost of good quality in the context of RFID is justifiable. In an earlier blog post, we discussed optimizing the cost of quality. In this post, we give an example analysis of RFID quality costs.

Analysis of the Cost of RFID Quality

Typically, the three main process steps in smart label manufacturing are chip attach, converting, and personalization. While the process details are specific to the manufacturer and machine, the analysis methods are universal:

  • Failure analysis: What is the impact of possible machine failures?
  • Process analysis: How do quality defects impact the process?
  • Cost analysis: What is the cost of quality defects?
Three main processes in smart label manufacturing

To remain in scope, our example analysis focuses on the cost impact of non-performing RFID tags in production. The case analysis is inspired by the case study presented by our customer Lab ID in our previous webinar session. In our modified case example, we are tasked with the delivery of 1 million labels to a customer. Let us assume that our manufacturing process has a yield of 98%. Out of the 1 million produced tags, 2% would be non-performing, meaning that these tags are bad quality or out of specification. Confronted with this reality, there are three possible actions to address non-performing tags which are described in the picture below.

Different scenarios that can play out based on the action taken to address quality testing and deal with bad tags

The first one is the baseline scenario for the case. We assume that cost and sell price per tag are 0.08 and 0.1, respectively. This leaves us with a margin of 20% for this production lot. In this scenario, we do not take into account any potential cost impact of 2% non-performing tags.

Base scenario – 2% of tags are non-performing

In the next scenario, we ride our luck and deliver all tags without addressing the bad ones. Thankfully, the customer does not notice any defects this time. While the 2% of non-performing tags did not have any repercussions on our margins, the last two scenarios showcase how repeating the action might bite us back the next time. We also do not consider the implications of how the bad tags will inevitably affect our customer’s business.

We get lucky – customer does not notice delivered bad tags

We can also do something about the bad tags. In the third scenario, we decide to test our tags and mark the bad ones during production. This would incur costs in the form of initial tester investment (a capital expenditure that is omitted from the costs of this single production lot) and marker ink (a largely negligible running cost). Marking the tags does not introduce extra production processes or require an operator to supervise the machine. With the help of the tester, we are able to mark the non-performing tags out of the 1 million. This sees our margins decrease slightly (20% to 18%) as we do not charge the customer for the bad tags.

Alternatively, we can also decide to test and then remove bad tags during production. Aside from the initial equipment investment as with the previous scenario, this also requires additional steps in the production, e.g. by handling non-performing tags with a splicing table and changing them to a normal one. This process also requires an operator overseeing the production process which induces additional costs. For our analysis, we assume this removal of a bad tag is ten times the normal cost of producing a tag. This would add a somewhat significant cost to us but our margins remain positive at 2%. Worth considering in this scenario is customers’ willingness to pay more for rolls with 100% working tags. This could help offset the extra costs associated with tag removal.

Testing tags – in both scenarios we can achieve a positive margin

Next, we deliver all tags, 98% good and 2% bad. This time neglecting quality has consequences: the customer notices defects in our delivery, returns the lot, and demands we rework them to reach the promised quality. This requires us to find the non-performing tags from the lot and replace them with good-quality ones. For our analysis, we assume all that tag replacement hassle along with the changes to production planning costs us 25 times the normal cost of producing a tag. Not only have our margins turned negative, but we also need to deal with an annoyed customer whose plans have been disrupted.

Final two scenarios – not testing tags can have grave financial and reputational consequences

In the final “doomsday” scenario, after delivering the production lot, the customer detects the defects, simply returns the lot, and stops doing business with us. Revenue for this production lot has been lost, our customer relationship is severely damaged and our reputation as a tag manufacturer is also at risk. Not addressing quality issues and providing no quantifying proof of quality can have severe consequences. As shown, a single batch of tags mixed some with inferior quality can do much more harm than expected.

Loss of customer relationships is difficult to measure in costs

Being able to quantify quality puts tag producers in a superior position to win and establish trust with customers. Getting there requires effort but as shown in our example it is a worthwhile pursuit in the long run. We are happy to help with your needs in getting there. A good resource to start with is our webinar on managing quality in RAIN RFID and NFC manufacturing.

On-Demand Webinar

Quality Management Approaches in RAIN RFID and NFC Manufacturing

Sep 10, 2020

Successful RAIN RFID Use is Based on Continuous Improvement

日本語版 Japanese version

Voyantic is mostly working with RFID technology providers. But I still discuss regularly with RAIN RFID users about their projects and challenges they have seen.

  • missing reads
  • stray reads
  • occasional faulty tags or readers
  • after a small change something doesn’t work anymore
  • and so on

The smaller technical issues often have a root cause in approach to RAIN RFID, especially how it is treated from a continuous improvement point of view. Sometimes (often) RAIN RFID is seen as a one-off IT project. The initial implementation often is an IT project, but when the system is taken into use, the project should not just be signed as complete, but it should be transitioned to the relevant operational organization and under continuous improvement. From this point of RFID has its own particulars.

Already in the implementation project, the continuous use should be taken into account. During the project, it is important to establish the specifications:

  • specify the tags including
    • performance
    • quality
    • tagging
  • specify the readers

Create a Tag Specification for Your RAIN RFID System

When specifying, use standards such as GS1 TIPP, or other methods to specify the performance. An unfortunately common way is to specify a tag or reader model. With a rapidly developing technology such as RFID, tying systems into specific component models is not the best long term approach.

Example of a tagging specification; what elements a specification should contain

This specification is the cornerstone of continuous improvement.

Establish Continuous Improvement and Problem-solving Practices

In several discussions, I have shared a version of a below continuous improvement outline. Let’s build the model step by step to see what it means in RAIN RFID use.

Let’s start with the basic: Do, Measure, Improve cycle.

When this is translated into the world of RAIN RFID use, the elements could be described as in below picture. The specification is the cornerstone of the continuous improvement cycle.

Next, let’s add some details:

Operations refers in this case to the RFID related operations. In-house operations related to RAIN RFID are reading the tags and possibly writing the tags, And then depending on the make or buy decisions, items are tagged, and someone is manufacturing the tags. All of these actions should be based on the specification: What are the tag requirements, how the items are tagged, how the tags are read.

When any system is used long enough, something changes. These changes should be reflected as changes in the specifications.

  • The changes and problems can be noticed reactively, that is: User notices that something is wrong, for example, missing reads in inventory counting, and reports the issue through proper channels.
  • The changes can be recognized proactively: There can be various checkpoints in the process and change implementations. Tagged items can be randomly tested; tags can be tested, new tag suppliers can be evaluated, etc.

If a proactive approach is used, suitable test methods need to be applied. The right approach is to have an in-house RFID test lab.

The same RFID test lab can also be used in problem-solving.

Implementing continuous improvement processes during the RAIN RFID implementation project helps to get the most out of the technology and investment. Transferring the RAIN RFID solution with development practices from project organization to operations ensures successful long term RAIN RFID use.

If you would like to discuss your RFID implementation or learn more about possibilities to set up an RFID lab, please contact Voyantic and request an online demo.

Aug 06, 2020

RAIN RFID in Tool Management

中文版 Chinese version

Recent developments in RAIN RFID technology, markets, and global regulations have made the RAIN RFID an even more interesting technology. I believe that with the RAIN RFID a traditional industry such as tool manufacturing can join the digital revolution. In this blog, I will explain why it is a good time for the tool industry to adopt the RAIN RFID technology and how to get started.

RAIN is a brand name for passive UHF RFID technology based on GS1 EPC Gen2/ISO 18000-63 standard

RAIN Is Ready

In 2006, IR DSRC defeated RFID technology and was chosen for the Electronic Toll Collection (ETC) System in Taiwan’s freeways. Six years later, in 2012, Taiwan’s ETC system was migrated from IR DSRC to UHF RFID technology, which transferred the freeways tolling system from a flat-rate and barrier-based to a distance-based and multi-lane free-flow on all of Taiwan’s freeways. ETC application is an example of how the market will correct technology selection with time. The tool industry is now facing a similar choice as ETC in 2006. Let’s hope the right technology is chosen from the beginning.

I started to see some companies providing tool management solutions with UHF RFID technology back to 2010. Frankly speaking, I was in doubt at that time if the market would value such a solution. The cost of adding an RFID tag on each tool was not cheap. Also, having a tag recklessly attached or glued on tools seems inappropriate and not professional as the tag protruded on tools’ surface may affect the tool’s usage and cause potential danger to tool users. More importantly, I did not see UHF RFID was ready for tools management in terms of technology maturity then.

Around 2015, Stanley Black & Decker launched tool management solutions aimed at minimizing the effects of FOD (Foreign Object Damage) and ensuring the right tools are in the right places at the right time. This kind of tool management solution is quite attractive in industries like aerospace, transportation, healthcare, manufacturing, and construction. Though barcode is one of the most widely used methods of tools tracking in today’s market, RAIN technology has many advantages over the barcode. For instance, RAIN enabled tools can be read without a direct line of sight even when the tools are covered with dirt or grease. And multiple RAIN enabled tools can be read at once when they are inside a box or bag. RFID Detection Bag is a good use case.

More importantly, more and more tag suppliers are starting to provide RAIN tags for metallic product applications, like industrial tools or surgical tools. Confidex, Omni-ID, Murata, Xerafy, and Etagsys are examples. Some of them can offer customized RAIN tag for the market. This indicates that the RAIN tag industry is ready to serve the tool manufacturing industry.

Built-in RAIN RFID as Part of Product

Using the tools’ metallic surface as an extension of the tag antenna to enhance RAIN RFID read range. A quite high percentage of tools are made of metallic materials, which normally play a negative impact on RAIN RFID performance. The below picture shows a RAIN RFID tag’s (6mmx2mmx2mm) read range when it is measured on air and attached on a metallic surface.

This tag is designed to cover Lower ETSI and FCC bands (865MHz – 930MHz). At the frequency around 920MHz, the tag read range is 0.8 meters when measured on air. If we put the same tag on a 15cm metallic ruler, just like the metallic surface of tools, the read range increases almost 100% to around 1.6 meters.

Tiny RAIN Tag measured on air and metallic surface, 4W EIRP with receiver sensitivity of -75dBm

An innovative tag antenna engineer should think about how to integrate the tag antenna into the tools and turn the challenges of metal into the advantages. Besides, instead of labeling or patching tags on tools after they were produced, embedding RAIN RFID tag into tools in design and production stages not only enables seamless tracking of each tool from the factory to the consumer, but it can also prevent people from removing RAIN tag easily.

Global Regulations

We know different countries have different regulations for RAIN RFID frequency bands. The good news is that Japan had migrated its RAIN RFID frequency band down to 917MHz – 924MHz in 2012. And the European Commission decided to add a new frequency band, Upper ETSI_915MHz – 921MHz, in 2018. By the time of writing this article, about 20 countries in Europe have adopted at least part of the Upper ETSI frequency band for RAIN RFID application. This means that sooner or later, we are going to have a global RAIN RFID frequency band which is allocated around 920MHz. What does it mean for the tool and RAIN RFID industries once the global frequency is widely adopted?

Global frequency simplifies the production of RAIN RFID enabled tools/items. The same RAIN RFID enabled tools can be used and sold worldwide. This will help to scale up production and reduce the cost.

This opens the possibility to optimize tag performance for the narrow frequency band tag around 920MHz. Either tags can be made smaller, or longer read ranges can be achieved, read more from Voyantic CTO Dr. Jesse Tuominen’s blog. Though the variation in the RF performance has a larger impact on read ranges of a narrowband tag than on a broadband tag, fortunately, Voyantic’s Tagsurance UHF has proved to be a great solution in tackling this challenge.

Global standards’ frequency range

No doubt, RAIN RFID provides much superior performance and potential capability compared to the barcode. However, the initial investment of adopting RAIN RFID technology is still more expensive. And it is true that RAIN RFID is not going to replace the barcodes entirely. In some use cases, the combination of RAIN RFID and barcode can be the optimal solution. But I want to point out: after a decade of market development, technology advancement, the cost decrease of RAIN components plus the global regulation change, RAIN RFID is now a feasible solution for the tool industry.

Benefits of RAIN Enabled Tools Management

I recently visited some tool manufacturing companies in Taichung and asked them what are the major problems that the tool users are facing. Their answers include lost, stolen, and misplaced tools. To be honest, I am a little bit surprised by such answers, but it again explains the importance of tool management. RAIN RFID is the ideal solution to reduce the pain points and inefficiencies. From the tool user point of view, RAIN RFID together with other IoT technologies can enhance tool management, for example:

  • Locating and tracking tools become easier
  • Improve security and avoid internal/external thefts
  • Increase tools utilization and availability due to full visibility
  • Minimize the effects of FOD
  • Enhance automation of alerts and reports
  • Eliminate human error and increase management data accuracy
  • Reduce total cost of ownership of tools

The demand for better tool management is apparent, and the market is huge and worldwide. The traditional tool companies surely need to think about how to take this demand as an opportunity and reinvent themselves with RAIN RFID. From my view, tool companies can gain invaluable business advantages if they successfully embrace RAIN RFID into their businesses:

  • Differentiate the product from the competition. This is an especially good opportunity for small and medium-sized tool companies to transform themselves from purely manufacturing to IT-driven business.
  • Sell more higher-value products than tools, for example, smart carry cases, smart drawers, and tools management software.
  • Facilitate sales if the IT system is well designed and developed. Then the customer can check data from smartphone and place order, for instance:
    • Data shows XX2 and XX5 are used over 90% of the time, click here and order both.
    • Data shows XX4 has not been seen in a month, click here and order a new.
  • Every RAIN enabled tool has a unique identification number which can be utilized for anti-counterfeiting and supply chain management from manufacturing to customer.

I am sure there are many more benefits that RAIN RFID can contribute to the tools management applications. I will leave some room for the imagination of the readers. Now let me briefly describe how to implement the RAIN RFID tracking system. There are some possible ways to carry out:

  • Tool company makes the whole solution in-house, including the IT system development and tag antenna design.
  • Tool company outsources RAIN RFID part to several different professional suppliers who provide software development, tag antenna design, and other components independently.
  • Or tool company cooperates with an RFID solution provider to cover all RAIN RFID related tasks.
  • Software company develops and sells tool management solutions to end-users.

It does not matter how the tool management solution is built; the performance and the tuning of RAIN enabled tools need to be carefully tested. Otherwise, the readability would be a big issue. And it is necessary to remind new players that commercial UHF reader is unable to verify RAIN RFID performance. After all, the reader is designed for the application, not for tag design and production quality control. SAG’s story in Taichung Taiwan will explain why it is important to utilize the right testing equipment in the R&D and the production line.


Once the performance of RAIN enabled tools is verified in the actual use case, the tool company can consider applying GS1 TIPP [Tagged-Item Performance Protocol] to streamline RAIN enabled tools specifications. GS1 TIPP is a RAIN RFID grading system developed initially for the supply chain management in retail, but it can be applied outside retail to scale up RAIN RFID applications across industries. Currently, there are fifteen TIPP grades, and tool company can select the grade(s), which can reflect the RAIN enabled tools’ minimal performance requirement. By doing this, it will simplify the communication among tool company, solution provider, and tag supplier. After all, grading is a much more efficient way to define the RAIN enabled tools’ performance. In case the existing grades do not meet the performance requirement, the tool company can submit a new performance grade to GS1 for validation or even create a custom grade.

TIPP Grades or Custom Grades can be used to verify RAIN enabled tools performance

In addition, the tool company can use the grade to source RAIN tag or RAIN enabled tools from several different suppliers if the specified grade level, tag size, and tagging method are met. GS1 TIPP also gives RAIN tag suppliers more flexibility in how they design the tag. This will encourage the tag supplier to be more innovative and creative to design the products to maximize the business benefit. Finally, any company can build its TIPP testing lab based on GS1 guidelines, and operating GS1 TIPP testing is easy and straightforward. This will help the whole tool industry to scale up the deployment of RAIN RFID technology.

Voyantic is the only company in the world specializing in performance testing systems for RAIN RFID and NFC tags from R&D to manufacturing. If you have any questions about managing the quality of RAIN enabled tools, feel free to contact us.

Apr 17, 2020

Triple Your NFC Label Production Capacity

中文版 Chinese version

In a recently published success story, Mr. Kevin Kuo, Technical Manager of a Taiwanese RAIN RFID and NFC tag manufacturer SAG discussed the improvements they have seen in production after taking the Voyantic Tagsurance HF system into use. He mentioned the improved capability to detect tags that are not working as specified, and also 200% increased production capacity. In this article, I explain more in detail some background features enabling the improvements.

“Tagsurance HF testing speed is much faster than normal commercial HF reader. The UPH has been increased over 200% after Tagsurance HF replaced the commercial reader in our converting line. Tagsurance HF can sort out those weak performance tags that a normal reader is unable to achieve. More importantly, Tagsurance can also record each tag minimum turn-on power, which is very useful information for our engineers to adjust the machine manufacturing parameters and to enhance the tag quality control.”, said Mr. Kevin Kuo, SAG Technical Manager. Let’s look at the two main improvements in detail.

200% increase in NFC label tag production capacity after installing Tagsurance HF

This amazing capacity increase was achieved entirely without adding new machinery. The capacity increase has its’ roots in the Tagsurance system. Tagsurance is an integrated real-time system, whereas typical NFC readers are combinations of a reader, computer, and reader software, or at least combinations of integrated reader + computer and software. These divided systems spend some time in moving data between the system parts. With Tagsurance, there is no time wasted on any overhead activities, and the data handling is optimized.


NFC communication standards are powerful and enable a large number of different use cases. The downside is that in typical use cases, the communication time is not minimized. There is a lot of communication flowing between the tag and reader, even in a simple read. The Tagsurance system is purpose-built for high-speed production quality testing. Some of the typical reader functionalities are left out, and focus is on a higher speed.

The difference is clearly visible when communication of Tagsurance HF and an NFC tag is compared to communication between an NFC reader (smartphone) and a tag. In the below picture, the communication is recorded with Voyantic Protocol Analyzer hardware and downconverter. The time Voyantic Tagsurance needs for checking the tag quality is a fraction of the time a typical reader needs when reading the NFC tag.

Recordings of the reader to tag communication between Tagsurance and an NFC tag; and a reader and a tag. Tagsurance HF needs a fraction of a time compared to a typical reader.

Replacing NFC reader with Tagsurace increases production capacity because Tagsurance HF:

  • is an optimized real-time device
  • does not need overhead time for moving data between system parts
  • is purpose-built for high-speed quality testing
  • uses NFC protocols efficiently for quality testing

-> 200% production capacity increase

Sort Out Tags With Weak Performance

Being a quality test device, the Tagsurance HF is capable of accurately sorting out good tags from non-performing ones. It is more interesting to look at why a regular NFC reader cannot do the sorting as well.

It starts with NFC tag performance. NFC tags are designed for different uses and are thus tuned differently, that is: the frequency where the tag needs the least amount of power is different. This frequency shifts to the 13.56 MHz HF RFID frequency only when the tag is in its typical use.

In the production line, the tag is not in its typical use environment, but the reader is still limited to operate on the 13.56 MHz. As a result, the reader only shows if the tag operates with 13.56 MHz in the manufacturing line. And how the tag works with a reader on the manufacturing line may be completely different from – let’s say someone is having the label glued behind a glass window or carrying a travel ticket inside a wallet.

In the below example, the tag with red tuning is out of specs, but in a production environment, it may even appear better than the good tags, even though in use, it requires a lot more power (does not work as well).

Tagsurance HF is not limited to the reader frequency. It uses the frequency that is relevant for determining the quality of each tag design.

Another limitation of a typical NFC reader is that they are not accurate and calibrated test devices. Many readers just have their own (high) power level designed to maximize tag reading probability; some readers may have a power setting but not calibrated. As a result, the readers cannot properly detect tags that are working out of specs.

Having exact performance information also enables production personnel to adjust the machine parameters based on real data, and to enhance the tag quality. Our expert team has seen many cases of the tremendous impact of the Tagsurance system in various production lines with ‘side effects’ being improved transparency to Quality Assurance and better communications with suppliers and customers. Tagsurance is truly a unique asset that can drive impressive results in the production environment.

Download the Tagsurance Catalogue

Learn in detail how the Voyantic Tagsurance UHF and HF testers can improve the efficiency of your organization!

Mar 16, 2020

RAIN RFID Deployed in High-Speed Production Machines: Aspects of Cycle Time

中文版 Chinese version

As RAIN RFID matures both technologically and businesswise, tagging requires scalable and flexible processes. I recently heard James Goodland, RAIN RFID Solutions Manager at NXP stating: “Going forward, the RAIN-ability of an item will be more likely integral to product design, rather than just added on an item” This implies a steady flow of new players and end-users getting into our industry, and the RAIN technology vendors need to be ready to support and help them out.

Beginning with this, the first of blog series with NXP® Semiconductors, Voyantic will address technical issues that should be considered when adopting RAIN RFID in various manufacturing environments. We shall start by understanding how the cycle time greatly affects your options, even down to the selection of the tag IC.

Translating Line Speed Into Available Cycle Time

Accelerating into the new decade 2020 RAIN tagging still dominantly relies on inlays which are converted either into tickets or labels. Printing of variable data, and encoding of RAIN labels, is done in a process that runs tens of meters per minute. Taking a figure of 30 m/min as a challenging benchmark example, and assuming a label or ticket length of mere 3.2 cm (1.25 Inch), the processing speed translates into 16 labels/sec.

Turning the numbers around 1 Sec / 16 labels gives 62.5 ms/label. This is the available cycle time in which you need to move in, process, and move out the label. If your RAIN encoding sequence stays within this cycle time, your production capacity stays unaffected.

Singulating the Tag Without Wasting Time

Quite often in a manufacturing environment, you need to singulate a RAIN label among others in the proximity. You can either use the protocol to do it or rely on skilled engineering.

Going with the protocol, you would first perform an inventory followed by the encoding process for the label. Inventory requires time specifically if high Q-values are used. This increases timing overhead, which you barely have in high process speeds.

An RF engineer can have a label singulated with careful triggering, use of dedicated antennas and appropriate reader settings. As a result, singulation does not add timing overhead at all. The Voyantic Ensurance solution supports both of these approaches. Specifically, in high process speed, we usually prefer to handle singulation based on the antennas.

Efficient Cycle Time Can Be Close To 100%

A label does not need to be in the optimal position in relation to the antenna all the time for a robust encoding system to successfully complete the job. Thus, the efficient cycle time can be fairly close to 100%. This means the reader won’t idle at all when the machine runs at the specified maximum speed.

However, if encoding fails at high line speeds, you rarely have the luxury to retry encoding. If you’re working with an encoding system that is not reliable or stable enough, but you want to protect the production yield, you may need to bring the cycle time down to < 50% simply to reserve the time for a second encoding try.

An alternative strategy is to have a second reader available to process the failed labels. Obviously a second reader adds cost, complexity and increases the space needed in the machine.

I would say that your overall preferred strategy in a production environment is to utilize RAIN encoding systems that have high reliability and high stability.

A Few Alternative Commands to Write With

All the GS1 EPC Gen2 (aka ISO 18000-63 standards family) ICs need to support the WRITE-command. The protocol also includes an optional command BLOCKWRITE, which was specifically developed to speed up the encoding processes.

It is up to the design of the IC to either support the BLOCKWRITE or not. Also, beware that the number of words that can be written with one BLOCKWRITE-command varies. Let’s look at how the NXP UCODE® 8 performs:

WRITE protocol control (PC) word, UID / EPC 96 bits and access password (nine words) + lock + read : 66.5 ms

BLOCKWRITE PC word (1 word at the time), UID / EPC 96 bits (3 blockwrites, 2 words at the time), and access password (1 blockwrite, 2 words) + lock + read : 49.4 ms

Only the latter case satisfies the example limit of 62.5ms and even leaves a comfortable margin to play with. With that said Blockwrite can be a lifesaver. At the same time, the example shows that specifying the encoding sequence using Blockwrite requires expertise.

RAIN Tag ICs Keep on Improving

The design teams of IC’s need to calmly work in a crossfire of conflicting requests: please deliver a tag IC design which boasts a fantastic feature set, is smaller than the previous model and complies with RED. “And yeah,” adds the marketing expert with colourful graphs, “kindly make the new IC also more sensitive than any other RAIN IC in the market. OK?”

“OK, no problem” responds the Engineering Director, takes a longer-than-average-sip of Dr. Pepper and starts orchestrating the design effort.

Eventually, the new IC lands at the Voyantic lab, where various issues will be verified and addressed:

RAIN RFID Tag ICs Benchmarked for Write Speed

One of the IC characteristics we look at is the time required to perform the WRITE or the BLOCKWRITE operation. You rarely find those numbers in datasheets, and even if you do, it’s really difficult to make sense out of them. Although meaningless for the majority of RAIN end-users, when one encodes labels at max speed, this timing parameter has to be known.

If you’re fascinated to learn more, please download the “RAIN Tag IC Encoding Speed Test Result Overview”. As we’re writing the UID / EPC, ACCESS password, locking the memory and verifying the UID / EPC, not all the IC’s are under the example target of 62,5ms.

Download Results

The write speed of ICs may be dependent on the protocol settings. For the purpose of this story, we have used the same settings for all the different ICs, and those are specified in the document.

Is That All?

There are plenty of fascinating details of how an encoding system is engineered to perfection, but if you’re either designing or operating a label processing machine, this is pretty much the story of encoding speed.

Read the next part in our blog series with NXP: Scaling Up with RAIN RFID Tags: The Path to a World Where Every Item Has Its Own Digital Identity