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

Jan 19, 2023

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

Liz Ann Sonders: GEL and demographics

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

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

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

Outlook of the retail market (Sonders cont.)

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

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

Remember this driver (Sonders cont.)

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

Observations from the exhibition floor

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

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

Outlook of the RAIN RFID market

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

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

Folks, we are in the right business.

Label-based tagging keeps on increasing

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

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

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

RFID applications closing in on the US consumers

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

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

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

Passive Bluetooth 

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

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

Three additional findings from the exhibition floor are worth mentioning:

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

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

Final thoughts

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

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RAIN RFID for Location Tracking Applications – Webinar Recap

Jan 17, 2023

RAIN RFID technology has been used for location-tracking applications for a long time. But the hype around IoT has given a new boost to companies exploring RAIN RFID’s suitability as a locating technology. In recent IoT tradeshows, our team has had several discussions about using RFID as an indoor locating (RTLS – Real Time Locating System) technology. So we decided to host a webinar to explore the topic further. 

Watch the webinar on-demand

This post summarizes the various RFID-based locating approaches covered during the webinar. Check out the webinar recording to also hear case study examples of utilizing RAIN RFID in locating applications and combining RFID with other RTLS technologies. The webinar guest speakers came from Turck Vilant Systems and Kathrein Solutions.

RAIN RFID as Indoor Locating Technology

Reader-based Location

The most common way to establish a location of an item is to base it on the readers. When you have a fixed reader and you know the location of the reader, you can determine the approximate location of a tagged item based on the reader reporting the tag. The location of the item will be within the set reader zone. For many applications, this approach works, for example in sports race timing applications. The reader could be placed also on a doorway to detect movement in and out, providing the room-level location. 

Readers at the finishing line detect when the runner’s tag crosses the line.

Tag-based Location 

A reversed method for reader-based locating is to have tags in fixed locations and track the reader location based on the fixed tag positions. The benefit of this approach is that tags are cheap. It is feasible to put many tags along known paths, for example, in elevators, trains, conveyors, floor tiles, etc. When the reader passes and “sees” a tag, that’s where you place it on the map. 

Tags at fixed locations reveal the reader’s location.

Locating Correct Items

Finding the location of a specific item, where something is, is a very common use case. For example, finding the right part in a warehouse or the right file in a large archive. A new product in the market that helps with this application is an LED tag. To find an item, a hand-held reader sends a select command to the item it is looking for. When a reader “finds” the item it is looking for, the LED on the tag lights up to visually aid the user to locate the item. 

The other method is using a “Geiger mode” with a hand-held reader. A reader can be set to show a “getting warmer or getting colder” indication when the reader gets closer to or further away from the item of interest. A sound indication beeping more frequently when the item is closer is often used – hence the method is often labeled as “Geiger counter”.

Reference Location Tags

Another good and common method for locating is to place reference tags in fixed locations where items are stored, for example on shelves and tables, in rooms, and at doorways. When you are doing an inventory with a handheld reader, you are also reading the reference tag in addition to the tags on your items and can determine the location of the items based on the known reference tag location.

Phased Array

Phased array is a fairly new method for locating RFID tags. This technology has existed for decades, mostly in the radar business. Phased array is a type of antenna consisting of multiple small radiating elements within one antenna housing, where controlling the phase difference of the elements allows the transmit beam to be steered in the desired direction. This allows you to scan your environment in different directions to find the tagged items. 

Overhead two-directional phased-array readers are becoming more popular. They allow estimating item locations with a single reader mounted on the ceiling, scanning left, right, back and front. The overhead readers work well when the items are big and the room is fairly empty. Shelves and furniture in the room causing reflections and echoes will have an effect on the accuracy. 


Using two or more horizontal wall-placed scanning phased-array readers enables determining the location with triangulations. You could also determine the location with one phased-array antenna placed on the wall if you know the angle and the distance range to the item. This technique is still rare and relatively expensive.

Range-based triangulation is a more traditional approach, where two or more readers find the item and can estimate the distance of the item from the reader. The distance data can be used to calculate the location of the item. But estimating the distance with RFID is not that simple. Typically in RF, time of flight is used, but with small distances, the time differences are too small for it to work accurately. Using RSSI is also tricky since it only works in one way. If you get a very high RSSI, you know the item is very close. But if you get a low RSSI, the item can be anywhere, far away, or close.

Using directional antenna-based triangulation and range-based triangulation for determining the location.

Phase-based Ranging

Phase-based ranging is a technique using backscatter phase measurement. In this method, you pick a channel and get a reply from a tag. The reply always comes at a certain phase. When you take the next channel or move up in frequency, more wavelengths are going to fit in the path from the reader to the tag and back, so the phase will increase. When you go to a higher channel number, the phase goes up (see the below graph). The phase rate of change is relative to distance and can thus be used to calculate the distance of the tag. If the phase grows fast the tag is far away. If the phase grows slowly when you increase in frequency, the tag is much closer. Regional channel regulations cause challenges for this approach, however. 

Inventory Robots

Using inventory robot technology for locating items is not very common yet, but it can be a good solution for doing inventory in large retail stores and warehouses, for example. The robot’s location can be tracked accurately with floorplans and rotary encoders, LIDAR, and other technologies. While the robot roams around tirelessly, its antennas can detect tagged items from hundreds of locations on its path. The accurate location of the items can be calculated from those data points in post-processing. This method is optimal when the items don’t move. Luckily the robots do not mind pulling an all-nighter, allowing the inventory rounds to be completed during the night.  

In Practice – A Combination

Usually, a combination of methods is the best approach. One RFID tag can be located through any of the methods. Let’s use a hospital as an example: 

  • It may be enough to know that a piece of equipment is in a specific patient room when in use: 🡪  gate readers. 
  • Item stored outside of cabinet can be searched with handheld readers: 🡪 Geiger counter
  • In the entrance area items a triangulated for preventing stealing: 🡪 triangulation with RSSI and beam antennas 

During the webinar, Peter Feldmann from Kathrein covered how a combination of RTLS and RFID technologies is used to locate forklifts in a warehouse.    

When to use RAIN RFID as a location-tracking technology?

This post scratched the surface of the different approaches to utilizing RAIN RFID technology for location tracking. Whether RAIN RFID is suitable, as a complementary or main technology, for locating applications depends on the use case and requirements. 

One of the clear benefits of RAIN RFID technology is that the tags are relatively low cost, coming in various forms and sizes, making the tagging of also lower-value and small form factor items feasible. One situation where it is smart to explore the potential of RAIN RFID for locating applications is when there is already a RAIN RFID system in place and the locating application could utilize the item data from existing tags and infrastructure. 

If you are interested in learning more, watch the webinar recording.

Voyantic tools

Voyantic Tagformance system includes an Application Development Suite (ADS). The ADS software is an ideal tool for optimizing RAIN RFID locating systems. 

The software package includes tools for determining forward and reverse link power margins with different locating approaches, a tool for optimizing antenna positions, and a tool for detecting phase shift, as well as tools for testing tag populations and interferences.

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Hospitals, Logistics, Automotive,… RAIN RFID is Everywhere – A look into RFID Research in 2022

Jan 03, 2023

It’s a new year and, again, a time to take a look at what’s been published in RFID research in the past year. I have done these yearly recaps a few times now (see posts from Jan 2022 here and from Feb 2021 here) as looking at the research field gives a good indication of what might become available for business applications in the coming years.  

Numerous RFID-related themes and topics were researched in 2022. Some popular themes were again sensor tags and healthcare applications. The RFID industry has grown strongly and that growth may have boosted research topics that are very close to practical implementations.

Advances in RFID Sensing

Sensor tags continue to be a popular research theme within RFID. Temperature is the most popular physical property being measured. Temperature sensing is followed by humidity sensing and pressure sensing. RFID sensors are being studied, for example, in pharmaceutical and food logistics applications.

RAIN RFID is used widely in tracking applications in logistics. Expanding the use of existing processes and infrastructure to also monitor freshness seems like a smart addition.

RFID sensing is not limited to the major physical properties. In 2022 many countries have seen energy prices soaring. 

RFID Sensing in Healthcare

Non-invasiveness of RFID is a driver of the study of healthcare applications. Researchers from University Tor Vergata have published studies of several applications such as:

Research Assisting RAIN RFID Implementations

Some research papers are tightly connected to RFID implementations, solving practical problems that have occurred.

RFID could be used to monitor underground pipes for corrosion and leakage.

The Voyantic Tagformance system with anechoic chambers has been used as a measurement and testing tool in many of the RFID research projects. Publications of several RFID research projects utilizing the Voyantic Tagformance system can be found at Google Scholar. Stable and purpose-built RF test conditions ensure reliable results in academic and commercial research projects.   

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