All blog posts

Why RFID TIPP Grading is Great News for the Retailers Worldwide

Nov 23, 2015

What does EU tax harmonization, the war in Ukraine, and TIPP adoption have in common? All three appear to be stagnant battlefronts with plenty of hard work done behind the scenes but minor visible progress to outsiders. Is there something wrong with the world order, how to move forward? Relax, take a sip of Dr. Pepper and read on to see why and how TIPP will prevail.

What Do TIPP, Tire Sidewall Codes, and Automotive Oil Grades Have in Common?

TIPP is an acronym for Tagged Item Performance Protocol. The TIPP methodology was initially created in the USA to simplify and standardize the communication and accountability around RFID tagging. RFID tagging of retail items dramatically improves inventory accuracy. Without RFID, it is impossible to sustain accurate inventory, especially on the shop floor level, and without accurate inventory a retailer cannot effectively execute their omnichannel sales strategies.

With this said, TIPP is a significant leap forward for any RFID adopting industry that looks to cut tagging costs, simplify communications, and clarify accountability. This approach would equally well serve the RFID adopters in the healthcare, automotive, and aerospace industries. It comes gift-wrapped by the GS1 US, too!

Little something for our friends!

The TIPP approach bears an analogy to car tire codes. The standardized information on the tire sidewalls describes the fundamental characteristics of the tire and is mandated by US Federal Law and EU Directives. Adapting to this system, the car manufacturer carefully masters the product (car) design, sets the tire requirements with a few alternative sizes that the car owners then follow. Periodically there is the unbiased 3rd party to check that a particular car has tires that meet the specs, are not damaged nor too worn out. In all these technical affairs, the tire manufacturer’s responsibility is to come up with the numbers and put them on the product. The tire brand is devoted to the sales and marketing side of things.

Tire sidewall markings include plenty of information for the consumer. “Tire code – en” by F l a n k e r – Own work. Licensed under CC BY 3.0 via Commons.

I will take a second example also from the automotive industry: SAE oil grades. Most car makers don’t endorse Total, Shell, nor Valvoline above others, but simply specify multigrade SAE 5W-30 in the owner’s manual, perhaps with little twists as BMW-LL-04. These grades have temperature-viscosity built-in, which makes a real difference up here in the North Pole. This valuable classification work was done by the Society of Automotive Engineers – SAE, which also has set standards on the quality side. SAE oil grades lay the grounds for easy purchasing, healthy competition, and results in fewer engine problems for us all. In this setup, the oil brands play an important role that is simply fenced off from the underlying oil grading system.

These two examples illustrate how grading systems have made two major industries more transparent, efficient, and streamlined. Sure it took years to develop and enforce these common practices, but the outcome benefits everyone.

Maintaining Approved Inlay Lists Becomes Too Complicated as RFID Tagging Expands to New Product Categories

Before the TIPP was established, the early adopters of RFID came up with their ways of getting tagging done in a controlled manner. Often this meant countless hours of the trial-and-error type of testing, and the outcome in many cases was lists of approved inlays that are suited for a particular product category. Suppliers were then instructed to use inlays from those lists, and just for a while, the process seemed to be alright.

Gradually the pain started to manifest itself. Because an inlay product is in constant evolution, maintaining of inlay lists often turned out to be quite a burden. To make the situation even more uncomfortable, the amount of testing is dramatically increasing as RFID tagging expands to new product categories. Even suppliers were unhappy due to extra effort and expense because conflicting lists from different retailers lead to exception tagging.

Adopting TIPP Is Evident, But There Are a Few Speedbumps Left on The Road

GS1 US did a fantastic job in pulling retailers, suppliers, and RFID industry experts together, and as an outcome, the TIPP grading system with eight initial performance grades was introduced in January 2015. The test methodology was documented on the protocol, physical and practical levels. A logical and well-documented alternative to the approved inlay list processes had been introduced.

The TIPP Guideline also includes grades for stacked retail items.

So why is it that the US retail’s giants did not instantly adopt TIPP? I would list four factors:

  1. The TIPP grades are not intuitive – which one to pick, and what to do if none of the eight alternative grades meet the read scenario requirements;
  2. How to verify for the TIPP grades – RFID technology vendors have not yet introduced routine validation methods for TIPP graded retail items;
  3. Many retailers are managing global supply chains, and they would rather adopt a global standard around RFID tagging;
  4. From the perspective of a multi-billion dollar retail company, slowness is an integral part of “instant”.

All these issues can and will be resolved; it just takes time. The road ahead is, therefore, paved with education, training, convincing, waiting, and politics. This rough terrain is nothing new since most RFID vendors are ideally used to it already for a decade.

Even slow progress is progress. Image courtesy of Hold the Mustard Postcards ©1980.

The Industry Is Multitasking And Making Further Progress

The vital steps that technology vendors and GS1 should take include making the TIPP grades more understandable, adding new grades in the portfolio, and introducing validation methods. All these issues are being addressed as we speak. In fact, for validation, there are already the first out-of-the-box solutions available, as you can see from the videos below.

On top of this great news, the GS1 Global Office is making a strong effort to develop a TIPP global standard. Retailers in the US, Europe, and Asia should all contribute and support GS1 in getting the global standard out promptly.

All this takes time. Many stakeholders are working on it, and it’s going to turn out great. Please contact me (juho.partanen@voyantic.com) for further insight!

Please accept marketing cookies to watch this video.

All blog posts
All blog posts

The Pioneers of UHF RFID: The Aerospace Industry

Nov 06, 2015

中文版 Chinese version

Retail RFID seems to get the most limelight in the RFID industry at the moment. And that is not surprising because of its huge tag volumes and growth rates. But many other sectors are benefiting from RFID use as well. One of my personal favorites is the aerospace industry.

The aerospace industry has been one of the pioneers in UHF RFID use

The most visible aerospace company in the RFID space has been Airbus. Their announcement, at the beginning of this year, to ask their supply base to tag all traceable items with passive RFID shows that they are serious. But also Boeing and Embraer come across regularly in RFID related news. To serve this industry, an ecosystem of RFID technology providers has emerged. Companies such as Fujitsu, Maintag, Tego, OAT Systems, and Brady, to name a few, have a special focus in aerospace RFID. Besides, the ecosystem has generated business opportunities for the supporting industry, see, for example, the Stanley Black & Decker success story.

What is Required from RFID in Aerospace?

So why are some RFID companies specializing in the aerospace industry? Can’t we just buy a roll of RFID labels and start tagging airplane parts? Well, it is not quite as simple as that. Several aspects set aerospace RFID, apart from many other application areas:

  1. Large memory required: The aerospace industry requires that a lot of information (birth records, maintenance records, etc.) is stored directly into the tag. They don’t want to rely on a connection to an external database which is usually used in retail RFID.
  2. Valuable items: The tagged items are of high value and are often used for ten years and more. As a result, tag durability is more important a driver than tag cost.
  3. Harsh conditions: Tags in and out of an airplane need to endure vibration, significant variations in temperature, humidity, and pressure, and many other conditions unfamiliar to retail applications.
  4. Global functionality: As airplanes frequently cross country borders and oceans, the RFID tags need to be readable around the world. As a result, the tags must be designed to be wideband.
  5. Less sensitive tag ICs: Due to their larger memory content and possible special functionalities, the tag ICs used in aerospace typically need more power. As a result, many applications are limited to read ranges of 15 cm to 3 meters.

A Need for Standards

The aerospace industry realized that they need standardization for flyable tags as early as 2006. That is when a group of experts in the field decided to develop a standard under SAE International. SAE AS5678, “Passive RFID Tags Intended for Aircraft Use” was born. The standard includes a broad set of different environmental tests to make sure that a tag would endure the harsh conditions of a flying airplane. Sun APT Test Center was the first lab to start certifying tags according to the standard.

In addition to environmental testing, the standard also describes RF performance tests for the tags. The standard described a very professional and well repeatable measurement methodology. But even more interestingly, the standard divided tag performance into performance grades, somewhat similar to what the GS1 TIPP standard would do for the retail industry in 2015.

AS5678 was truly ahead of its time.

As a result, an airplane manufacturer could simply require a grade B tag to be used by its suppliers without having to specify the tag model or detailed performance parameters.

AS5678 performance tests are typically performed in a small anechoic chamber

Now, in 2015, SAE is revising the AS5678 standard to reflect the new information gained during the years. I have been a member of the team, revising the standard as well. The changes, however, are not very large, which well reflects the quality of the first standard version.

Specific RFID Testing Needs of the Aerospace Industry

The special requirements of the aerospace industry for RFID lead to some specific testing needs:

  1. Measuring tag performance: Because of the large memory contents, wide bandwidth, and rugged design, aerospace tags may have limited read ranges. The AS5678 test methodology can be used to determine the acquired read range and the matching performance grade.
  2. Verifying tag bandwidth: Since a wide bandwidth is required, the performance of the tag needs to be tested typically throughout the 860-960 MHz frequency range.
  3. Environmental tests: AS55678 describes a large set of environmental conditions that the tag needs to endure. The performance of the tag should not degrade during the tests.
  4. Memory testing: The memory of an aerospace tag is organized differently compared to a typical label. As a result, there is a need to have good visibility to the tag memory contents.

My company Voyantic has delivered test and measurement systems for both end-users and technology providers in the aerospace RFID industry. The systems promote design and manufacturing excellence, as well as fluent technical dialogue between pioneering companies within the industry.

If you are interested to learn more, please download our application note below or contact us, and let’s talk more!

Learn How to Test UHF RFID Tags in the Aerospace Industry

Download The Essential Guide for UHF Tag Testing in Aerospace

All blog posts
All blog posts

National UHF RFID Standards and RFID Performance

Sep 14, 2015

ISO 18000-63 (6C, EPC Class 1 Gen 2) has been by far the most used UHF RFID standard for several years. There have been some competing standards such as Tagidu, IP-X (tag-talks-only), and ISO18000-62 (6B), but they are nowadays rarely used in new applications. However, new RFID standards still emerge: for example, in Brazil, SINIAV has created a protocol aimed for vehicle tracking applications. In China, a new UHF standard, GB/T29768-2013, has been recently published.

Several tag manufacturers work with these new standards. Why do these national RFID standards exist? And what does it mean for performance testing?

Why Doesn’t Everyone Work with the Same Standard?

Since there is a well-working global standard, it would sound logical to use it for as many applications as possible. But there are some reasons for using something else as well. There may be national interests, or maybe there are special requirements that existing standards don’t cover well enough. For example, ISO 18000-63 was developed for quickly inventorying large quantities of items, and it may not be optimal for reading a single tag that is passing by at 180 km/h. Another challenge may be when the tag is in the windshield of a truck filled with other tagged items.

It should also be noted that the division to separate standards does not always have to be final. Commonly, new functionalities and exclusive features are absorbed into the global standard after they are validated.

What is the Difference Between the Different Standards?

When we talk about passive UHF RFID, we talk about readers that radiate between 860 to 960 MHz to power up remote tags, which in turn modulate their reflection to communicate back to the reader. That is common between all passive UHF RFID standards.

The difference is in how the readers and tags modulate the electromagnetic waves, and what kind of command and response sequences are used in the communication.

One standard might be optimized for quick inventorying while another might provide added security.

Besides, the complexity of the protocol affects the power consumption of the chip and, thus, the read range that can be acquired.

What do the National Standards Mean for Tag Manufacturers

So how should a tag manufacturer respond to a customer’s request to make a tag for a less widely used UHF RFID standard? Well, that depends on the opportunity. But there is nothing to be afraid of in the design process – it is no different from ISO 18000-63 tags. The Voyantic Tagformance system supports performance testing of the GB and SINIAV protocols (as well as older ISO 18000-62 and IP-X protocols).

With the Tagformance system, it is quick to characterize a UHF RFID tag regardless of the protocol: just choose which protocol is to be used in testing and then start the selected test. Results include (but are not limited to) information about the tag sensitivity, read range, tuning, and radiation pattern.

Application Developers

New RFID standards are often used in new application areas. With the Voyantic’s Field Engineer’s Kit, RFID tags can be tested within the application – for example, when attached to a vehicle. Vehicles are an example of a quite challenging environment for RFID because of their large metal parts and a variety of different plastic and glass types where tags are mounted. Thus, field test results are crucial.

Typical field tests aim to verify the read range. The Tagformance system can be used in evaluating what kind of read range can be achieved with different readers – without actually using the readers. Based on the tag measurements and the reader information input by the reader, the system shows the achievable read range, but also which tag or reader parameter is the bottleneck for system performance.

Download the Tagformance Pro Catalogue

Learn more about the Voyantic Tagformance® Pro Test Device! By combining RAIN RFID and NFC testing into one compact test device, our all-new Tagformance Pro is a true all-in-one tool for anyone either developing or using RFID technology.

All blog posts
All blog posts

The Convergence of UHF RFID and NFC

Aug 27, 2015

I saw my first combined UHF RFID-NFC apparel label at a trade show several years ago. I remember wondering what the reason for this combination was. After all, UHF RFID is primarily used in the business-to-business world of retail: supply chains, inventories, point-of-sale, etc. NFC, on the other hand, is used in the business-to-consumer interface: in retail, primarily brand enhancement. Could there be a reason to combine these two technologies?

The label sales guy politely explained to me that the reason for the combined label was precisely that, addressing both the B2B and B2C needs at once. Since the apparel supplier is already required to tag all his products with UHF RFID to accommodate the retailer’s inventorying needs, why not put in NFC as well?

The Cost

Of course, there is an added cost of adding NFC functionality to a label. But the supplier is already purchasing labels. There is a process in place for attaching the labels to the garments, and, hopefully, there is already some kind of quality assurance process. Ideally, adding NFC functionality costs little more than the additional cost of the NFC inlays.

The Benefit

But what do the apparel suppliers, or better the brand owners, get out of this? They get a chance to use the store as their marketing media. As a consumer taps a product label with an NFC enabled smartphone, they are taken to a dedicated web page where the brand owner can interact with them. The consumer may receive detailed information about the product, or they may be offered promotions for that specific product or other ones. The possibilities are endless. Besides, the brand owners gain information about who is interacting with the products and when each can be used for planning future marketing activities.

Latest Developments

The combined UHF RFID-NFC label that I saw years ago was based on separate UHF RFID and NFC inlays. But at the beginning of this year, EM Microelectronic launched a new product that could change this approach. The EM4423 is, according to their own words, “the world’s first RFID circuit featuring a UHF EPC Gen2V2 RF and an NFC Type 2 interface”. Several tag manufacturers are working with the chip, and we should expect to see new exciting products by the end of the year.

What Does the Convergence Mean for RFID Testing

Combining two antennas into a single tag adds a new layer of complexity. The UHF part should work with all RFID readers: handhelds, gates, POS, and so on. And NFC should be conveniently usable for consumers with their various smart devices. Optimizing tag design for both needs is more demanding than designing a single frequency tag. Also tagging the items must be reconsidered: tag placement must serve reliable inventory counting and allow convenient consumer access.

My company Voyantic’s focus has always been in performance and quality testing of RFID components, both UHF and HF/NFC. Lately, we have seen more and more companies developing and using UHF RFID and NFC technology side by side. To better serve our customers, we have been working the last couple of years to build a test system that would allow testing both of these technologies. Our goal has been to enable the rapid development of new, cost-efficient tag designs and to deploy them into a reliable system.

Tagformance Pro combines UHF RFID and NFC testing in one device

Tagformance Pro combines UHF and NFC tag testing into one device. The Tagformance Pro supports tag design, tag selection, and planning of tag placement – both UHF RFID for inventory and supply chain and NFC for the consumer interface. Tagformance Pro is a real all-in-one tool for anyone either developing or using RFID technology.

Download the Tagformance Pro Catalogue

Learn more about the Voyantic Tagformance® Pro Test Device! By combining RAIN RFID and NFC testing into one compact test device, our all-new Tagformance Pro is a true all-in-one tool for anyone either developing or using RFID technology.

All blog posts
All blog posts

Tagged-Item Grading Helps Retail UHF RFID Projects

Aug 14, 2015

Retail and the retail supply chain are among the most significant users of UHF RFID technology. However, retail RFID projects are not the most simple ones. Items in retail come in all shapes, sizes, and materials. They are shipped in different boxes and stored and displayed on all kinds of racks, shelves, and tables. Also, different readers are used in various applications: logistics tracking, inventory count, RFID EAS, POS, and so on. I was involved in several retail RFID projects, and I have seen how complicated the performance optimization can be.

GS1 Tagged-Item Performance Protocol (TIPP) was developed to help retail RFID by making buying and selling tags easier. But what do the TIPP guidelines mean, and what kind of testing is required?

Goal: Accuracy in Inventory Counting

The purchase of RFID tags for retail items used to be complicated. The goal is simple: to have good counting accuracy (read rate) and a long and controlled read range. But I have seen how simple read range and counting accuracy requirements turn into a complicated mess of lengthy and costly field testing and piloting. Tags and readers are often selected separately, and system-level optimization is left to a trial-and-error process, if not entirely forgotten.

One approach used to be describing various use cases in detail and relying on the suppliers and technology providers to deliver tags that would work in all of the applications. The supplier was accountable for performance but had in practice minimal possibilities to achieve the goal.

Another strategy was to test extensively and to list accepted tags for different product categories. That way, the supplier was no longer accountable but was forced to buy specified tags without a possibility for price competition.

Finally, when using TIPP, the supplier is accountable for performance, and also has all the tools needed for delivering and verifying it.

Tagged- Item Grading Makes Retail RFID Projects Easier

The Tagged Item Performance Protocol makes buying and selling tags easier. The idea is familiar with many goods, from engine oils to clothes. It is a lot easier for a buyer to purchase shoes of size 41 than to provide a list of different measures of the foot. And it is a lot easier for the supplier to produce, stock, and sell shoes with a few different sizes than to verify that the unique requirements of each customer are met.

Similarly: it is easier to buy and sell tagged items performing according to a grade S05B than to list and verify all relevant performance requirements individually. As a result, a retailer’s list of requirements could be, for example:

  • items to be tagged with UHF RFID tags with C1G2 protocol
  • tagged items following GS1 Format & Symbol Placement for the Electronic Product Code guideline with C1G2 protocol
  • performance according to GS1 TIPP S05B grade
  • coded with SGTIN-96.

Now there is no longer a need to describe in detail which RFID tags to use and how to place them. Also, the suppliers and tag providers don’t need to guess what the use case description means from an RF performance point of view. TIPP translates complex system-level requirements into simplified component level pass/fail verification that any vendor can handle themselves.

The Voyantic Tagged-Item Grading System is 100% aligned with the GS1 Tagged-Item Performance Protocol (TIPP). The system automates TIPP grade validation and testing and provides results quickly and easily. It also enables TIPP grade audits to be performed by anyone. The Voyantic Tagged-Item Grading System is available as a complete turn-key setup.

Want to learn more? Read more about the Voyantic Tagged-Item Grading System! Don’t forget to download our handy tool for evaluating read ranges with different RFID readers and tags with various TIPP grades below!

Download a Tool for Evaluating Read Ranges

Download a handy tool for evaluating read ranges with different RFID readers and tags with various TIPP grades. In the tool you can select a TIPP grade, input reader parameters, and see what kind of read range is expected from the system.

All blog posts
All blog posts

How to Improve Efficiency of the R&D Team in UHF Tag Design

Jul 23, 2015

中文版 Chinese version

Being responsible for sales of RFID performance measurement solutions, I’ve had the privilege of meeting with several companies and their design professionals around the world using very different methods for measuring UHF tag performance. Which is the best method then? I’d say it depends on your requirements – for a single essential measurement, you may use various methods, and even a simple technique can be sufficient. However, if you are looking for a way to improve the throughput and efficiency of your R&D team in tag design, the differences in methods are enormous. So, where does the efficiency come from?

The simplest method in UHF tag measurement is using an RFID reader to verify if the tag can be read from a certain distance or not. This pass/fail type of method is easy to do and fast for sure. However, most of the critical characteristics cannot be measured nor verified at all. Another commonly used way based on a set of generic measurement instruments like a signal generator, a network analyzer, and a power meter, is more advanced but unfortunately not anymore fast nor easy to use.

As the two methods introduced above are not ideal in the first place, neither of them can be the real solution to provide increased efficiency either – don’t worry, there is another approach available.

Purpose-built RFID Measurement System

In the R&D environment, most RFID measurements set high requirements for reliability, accuracy, and repeatability of the results and the test method itself. This is the case also in developing new UHF tag designs, thriving to the best possible performance, and at the same time balancing various requirements for different parameters. In this kind of environment the key questions are;

  • How quickly can a set of various measurements be performed?
  • Can the measurements be repeated automatically during the design iterations?
  • What are the possibilities in storing, analyzing, and sharing the results?
  • What kind of competence is required to perform the measurements?

The ideal solution addressing these requirements is a purpose-built RFID measurement system, providing an easy-to-use user interface, high measurement accuracy, compliance with standard RFID protocols, and wideband sweep capability.

How to Enhance the Efficiency of the R&D Team?

Ease-of-Use

There is inherent ease-of-use in the concept of a purpose-built measurement system, as there is only one tester device, including all the necessary accessories and an easy-to-use graphical user interface. A predefined measurement set-up procedure based on a reference tag ensures correct system start and exact measurement results.

Ease of use improves the efficiency of each user regardless of their technical competence. However, the real benefit comes out of the fact that also less experienced persons can easily be trained to perform extensive measurements without having in-depth RF knowledge.

One System – Several Measurements

A dedicated RFID measurement system includes all the necessary measurement functions presented in a pull-down menu with suggested default settings for each measurement. Wideband sweep measurement performed over a wide frequency range of e.g., 800 – 1000 MHz enables the flexible visual presentation of the tag detuning phenomenon on different materials compared with on-air results.

Measurement functions menu

One Measurement – Several Results

One single measurement, like the Threshold Sweep, provides several calculated results (e.g., Transmitted power, Backscattered power, Electrical Field Strength, and Theoretical Read Range) that can be viewed simply by selecting the desired result view from the Y-axis pull-down menu.

Results selection menu

Repeatability and Automation

Once the user has selected the function and started the measurement with relevant parameters, the test system provides the results that are stored in the results database with a timestamp and detailed information on all the parameters used in the measurement. Error-prone human interaction and handling of the results are avoided by automated calculation and management of the results.

The quality of the measurements can be further ensured by defining and storing a sequence of measurement commands (Scripter) for repeated use. Predefined script together with automatic rotation system eliminates human errors when performing e.g., orientation sensitivity measurements in various positions between 0 and 360 degrees. The example script below defines a sequence of two Threshold measurements and one Backscatter measurement.

Example of a measurement script

Conclusions

A purpose-built RFID measurement system combines high measurement accuracy, versatile measurement capability, and ease-of-use – a unique combination that cannot be achieved with traditional methods.

Accordingly, the improvement of the R&D team efficiency is based on:

  • Quick set-up of the system
  • Better visibility to the performance of the tag under test
  • More measurements in the time available
  • More tests on alternative tag designs in a shorter time
  • Avoiding human errors
  • Testing made it possible for non-RF specialist
  • Shorter time to market for new tag designs.

If you want to learn in detail how the Voyantic Tagformance UHF Measurement System can improve the efficiency of your organization, please download the Tagformance Catalogue below! 

Download the Tagformance Pro Catalogue

Learn more about the Voyantic Tagformance® Pro Test Device! By combining RAIN RFID and NFC testing into one compact test device, our all-new Tagformance Pro is a true all-in-one tool for anyone either developing or using RFID technology.

All blog posts
All blog posts

Why UHF RFID Tag Developers Should Use Wide Band Performance Testing

Jul 10, 2015

中文版 Chinese version

RFID reader frequencies are controlled by governments and limited to narrow frequency bands that vary around the world. When the performance of a UHF tag is evaluated, focusing only on the narrow reader frequency bands is misleading. I have seen in several RFID projects, how the tag performance in field conditions is different from what is expected, leading to delayed projects and expensive re-planning. Testing in a wide frequency band is needed to get the correct information about and good visibility into UHF RFID tag performance.

Detuning as a Challenge

Typical UHF RFID tags operate with a wide frequency band. However, performance still depends on frequency. In UHF RFID tag development, the tags are usually designed to have maximal read range at the reader frequency. This is achieved by tuning the tag to be most efficient at these frequencies.

Succeed in RFID projects with wideband testing

Detuning creates challenges:

When the tags are attached to different materials, their performance at the reader frequency changes.

The entire performance curve shifts on the frequency scale and a change in read range is observed at the UHF RFID reader frequency. This detuning effect is one of the fundamental physical phenomena affecting real-life RFID system performance. If the detuning is not taken into account, the UHF RFID tag’s read range may be only a fraction of what is intended.

In good design, the detuning is anticipated and taken into account. If the tag is intended to be used on a material that causes 50 MHz of detuning, it can be tuned to have optimal free air performance at a frequency 50 MHz higher than the reader frequency. When the tag is on the material, the tuning and performance become optimal.

If the tag is only tested at the reader frequency, it is almost impossible to design the tuning correctly. A wideband view is needed.

Comparing Tag Designs

An example: An RFID user manufactures items made of rubber. The items are delivered on a cardboard package. The user wants to tag the cardboard boxes and wants to have a maximal read range. The items are shipped, and the RFID tags are read globally. What kind of tag would be the best?

Two tag designs were tested using UHF RFID readers with ETSI (865 MHz -868 MHz) and FCC (902 MHz – 928 MHz) frequency bands. In the test, the reader was moved closer to the tag, and the distance was measured when the tag was read the first time. Each test was made twice.

The results show a big difference in read ranges. Tag design A has a 12 m read range on cardboard, but only 5.5 m on rubber. Tag design B has an opposite performance change: 11 meters on rubber and 6.5 to 8.5 meters on cardboard. There is also a difference between repeated measurements, which is significant, especially on the FCC frequencies.

What Really Happens with the UHF RFID Tags?

Because the reader frequency is limited, it is difficult to get a good overview of what is happening when the tag is attached to different materials. The read range is different in various test scenarios, but it is not clear why. Some explaining phenomena immediately pop into the minds of RFID professionals: multipath propagation and detuning. But the results from reader frequencies do not tell how the detuning works.

Which tag would you recommend? Click below to view the wideband test results of the Tags A and B from the Tagformance system or send me an email and let’s talk more! Voyantic offers RFID measurement systems to help tag designers. With precise test results, it is easier to give recommendations with confidence!

Download the test results

All blog posts
All blog posts

Is Now the Time for Passive RFID Sensing?

May 29, 2015

One of the hot topics at this year’s RFID Journal Live! trade show in San Diego was passive RFID sensing. The show featured several new sensor products from companies like RF Micron, Smartrac, Phase IV Engineering, Farsens, and many others. But what is passive RFID sensing all about? And should you already be working with it?

The rise of passive sensing has been noticed by other people as well. Mark Roberti, the founder and editor of RFID Journal, gave special mention to some of these solutions in his article.

As a matter of fact, four out of the ten Best New Product nominees at the show were related to passive RFID sensing.

In addition to the announced new products, there seemed to be a lot more bubbling under. I had numerous discussions at the show with companies that were at least looking into adding passive sensing into their product portfolio.

Passive RFID Sensing Is Nothing New to the Academic Community

I have been following RFID related research for almost 15 years, first as a researcher myself, lately more through the work of Voyantic’s academic customers. I have also been a member of the technical program committee for the IEEE International Conference on RFID since 2009, which has had me read dozens of scientific papers in the field. Passive sensing seemed to come up more in scientific papers about five years ago. Among localization and energy harvesting, it was one of the topics that I was expecting to transition to the industry at some point.

Passive RFID sensing presents new challenges for manufacturing testing

Typical academic sensor concepts are based on measuring an environmental parameter through changes in an electrical property of a passive RFID tag. I have seen numerous papers on sensing.

  • atmospheric variables such as temperature and pressure
  • mechanical variables such as strain and dislocation
  • chemical parameters such as the presence of different gases and corrosion
  • even the fullness of a beer glass.

However, academic research usually goes only as far as is needed to prove the concept. And that is where all the hard work should start, including proving the ROI of the sensing solution, creating reliable calibration methodology, and manufacturing the sensors cost-effectively.

The sensing solutions that we saw at the RFID Journal Live! are somewhat different from the earlier academic research. In nearly all solutions, the sensor data is read with a regular RFID reader from the memory of the tag IC. The data may be logged into the tag memory with the help of an on-tag battery, or it could be updated at the time of reading the tag.

What Does RFID Sensing Mean for RFID Technology Providers?

For a tag manufacturer, sensor tags present an exciting opportunity to generate value-added products. Sensor tags are more complicated than the most uncomplicated labels, which could allow higher margins. Also, they could allow differentiation from the high-volume, low-cost retail label business. So it is no surprise that a lot of tag manufacturers are looking into the technology.

Passive sensor tags also present some specific design challenges. Of course, sensor tags have to react to the particular environmental parameters in a predictable manner. In addition, the tags should remain readable no matter what the conditions.

Tag design verification should include simultaneous sensor functionality testing and performance testing.

The same holds for manufacturing the tags. Instead of a simple pass/fail testing, sensor tags require testing for functionality and performance. Besides, the sensors may need to be calibrated at the time of manufacture.

Passive RFID sensing presents new challenges for manufacturing testing

So How to Move Forward?

To conclude, the technology for passive sensing is out there. It may not be perfect, but it should be good enough for successful applications. But I guess working in a technology startup for so many years has made me a little cynical towards technology platforms.

Whichever technology is used, it is really up to bringing value to the end solution.

The key drivers in the possible advancement of passive sensing are application developers that are familiar with a specific industry and their problems.

Are you interested in this topic? Download our application note below!

Learn How to Design Passive Sensor Tag

Download our application note “Utilizing Voyantic Tagformance to Speed Up Development of UHF RAIN RFID Sensor Tags” to learn how to design passive sensor tags!

All blog posts