Q&A of RFID Sensor Tags

Q: Can AS321X Family get sensor values via LLRP protocol?
A: Only standard EPC commands (inventory and read) are needed to get the sensor data, so, yes, you can get sensor values via LLRP protocol (if your UHF RFID reader is compatible with LLRP).

Q: Can you make RFID tag with sensor that would be embedded into rubber or other material?
A: As mentioned during the webinar we do a lot of custom tag designs through our DesignStudio service, and there are also a lot of embedded tags into several different kind of items. All of these could potentially be using Asygn IC. As an example, we are embedding tags into tires so enabling temperature sensing of rubber would be possible utilizing learnings from our standard embedded tag.

Q: Does using hard tag for temperature measurement affect the temperature measurements?
A: Indeed it does when it comes to the speed of the temperature changes. When the IC is protected inside the plastics it takes a bit of time to follow the temperatures outside of the enclosure, so if you need to react to fast temperature changes, like seconds that we saw in that video during the webinar, then it would be good to think if label type of product would be a feasible solution. But if it is not about seconds but minutes, then hard tag would be still feasible.

Q: How does the motion sensor tag work? And what’s the output when reading the tag?
A: Motion sensing can be achieved with external capacitive accelerometer connected to AS3213C IC. When reading the tag, you get a raw sensor data (figure between 0 and 1023 in decimal).

Q: I need to record in tag the surpassing of a temperature up to 250 °C and read it only when I access to tag at normal temperature?
A: Confidex has experience in producing RFID tags with temperature resistance exceeding 250 °C, so from tag perspective this is possible. Measuring the temperature over 125 °C requires an external temperature sensor to be connected to Asygn IC.

Q: Can the temperature inside somewhere be read e.g. a fridge/freezer?
A: This depends on the material of the item where tags are inside. RFID tags are not readable through metal but can be read through other materials. Reading through fridge or freezer door should be OK.

Q: How much tag memory is used by sensor data – is there enough capacity to, for example, store the TID, an EPC data field such as GLN, and also the sensor reading?
A: Only two 16-bit registers (mapped in USER bank) are needed to store the two sensor data. In addition, six 16-bit NVM words are available in USER bank to store calibration data and specific user data if needed. The AS321X ICs also include RESERVED, TID and EPC banks compliant with the EPC GEN2 protocol. The length of the EPC code can be as high as 192 bits.

Q: Can RFID tags capture the temperature to download more later? We need to trace the range of temperature.
A: Asygn IC is not a data logger; data is captured by reader and need to be transferred to cloud or any gateway.

Q: Inlays are unreadable when affixed to metal, though, by bringing the IC into contact with the metal surface, the temperature and stress values will be known more accurately. What will the hard tag look like?
A: It is possible to design for example Ironside Slim type of hard tag where the IC is on the backside of the tag, close to the metallic item. But this would decrease the performance of the tag compared to more traditional antenna design.

Q: Temperature sensor tag, can it put temperature sensor somewhere else not where the tag is applied? It will measure the surface of sensor or tag?
A: An external temperature sensor, like a PT1000 sensor for instance, can be used with AS321X ICs (a specific custom tag needs to be designed).

Q: Tags on ESD materials also can be read by portal gates, even though put 4×4 bins together in a pallet?
A: ESD material is a challenge for RFID tags. Therefore we have designed a product specifically for that, ESD On Metal Label. With this product it is possible to read ESD boxes also with portal readers.

Q: Humidity sensor tag can detect water leaking?
A: It measures percentage of Humidity in the air, so can indirectly measure some leakage. But we can also connect a capacitance on a tag directly connected to our AS3213C IC able to detect leakage, or moisture.

Q: What sensor type of demo apps that are available?
A: There are demo apps available for selected reader models. Please reach out to Confidex for more information.

Q: What is the relation between distance of sensor tags and different PDA power without sacrificing the temp accuracy?
A: The level of RF energy has a direct impact on the reading distance but not on the accuracy of the sensor. You can contact support@asygn.com to get some recommendations for optimizing accuracy of your sensor measures depending on the temperature range targeted in your application.

Q: Do you have a chip capable of sensing shock?
A: This can be done with an external sensor connected to AS321X IC.

Q: Is there an SDK we can use to make our own software?
A: Only standard EPC commands are needed to get the sensor data. Depending on the reader you use, a SDK can be provided by the reader manufacturer. Most of reader manufacturers already have demo software to quickly compute temperature and Humidity.