Passive RFID tags based on sensors have gained a strong growth in recent years. In some market segments, such as temperature and humidity testing market, sales have far exceeded that of battery powered passive tags (BAP). A report by IDTechEx showed that in 2017, 5 million 200 thousand passive RFID sensors were sold in the market, while BAP RFID tags sold only 330 thousand.
The passive RFID tag based on sensors has gained a strong growth in recent years, according to IDTechEx, a British market research firm. In some market segments, such as temperature and humidity testing market, sales have far exceeded that of battery powered passive tags (BAP). A report by IDTechEx showed that in 2017, 5 million 200 thousand passive RFID sensors were sold in the market, while BAP RFID tags sold only 330 thousand.
The company predicts that in the next ten years, the sales of active and passive RFID sensors will reach $400 million, and the solution will reach $904 million. The size of the RFID market in 2027 is expected to reach US $20 billion, and the growth rate of sensor labels next year is expected to reach 12%.
This study compares passive and active RFID sensor systems, including high frequency (HF) and ultra high frequency (UHF) tags, provided by about 50 companies worldwide. Raghu Das, chief executive of IDTechEx, said that over the past year, the number of RFID sensor vendors has been increasing with the popularity of UHF and NFC applications and the decline in cost.Das says battery powered RFID tags are 15 years old, but use cases are very limited. He said: "because of price factors, the sales of these products are not good. The study found that the average price of the battery powered RFID tag is US $16, which is much higher than most of the estimated price of the application.
In recent years, with the introduction of sensor based RFID integrated circuits, the cost of RFID sensor tags has dropped to less than US $10. But it still limits its use scenarios to high value goods or reusable scenes.
RFMicron and other companies have provided a series of restricted passive sensor products. When there are no on-board batteries, these sensor labels cannot store data and can only respond to queries. But in some scenarios, data needs to be stored.
For example, the leak detection tag is used to detect the leakage of new vehicles at the production site. Because labels are cheap, there is no need to reuse them. They can also be used to leak out the electronic products.
Another common use case is tracking the moisture content of adult diapers in medical institutions. In this scenario, the nursing staff can use the handheld reader to read the label data without physical contact, which can save time and improve the patient's comfort.The system can also be used with a fixed card reader. Das cited an application where the temperature of key components in mechanical equipment needs to be tracked. For example, wind farms can install fixed UHF RFID readers in wind turbines and attach passive RFID sensor labels to each turbine blade. This card reader can ask the sensor data when the blade enters the reading range to confirm whether the temperature is abnormal.
So far, the number of passive UHF sensor tags exceeds the number of NFC tags. The study found that among the IC manufacturers of these labels, 42% were based on UHF chips, 35% were based on NFC, and the other 23% were capable of simultaneous NFC and UHF transmission.Another passive biosensor, passive RFID sensor, is also being launched. They are being used in research and pilot projects. At present, the annual sales volume of this type of products is less than 5000 units. The biosensor label uses the sensor membrane connected to IC. When the specific conditions are met, the RF transmission will change when the tag reads.
The production cost of biosensor labels is very low and can be used to track conditions other than temperature and humidity. For example, if biosensors detect explosives or specific chemicals, the transmission state of these labels can change. However, these tags require a dedicated card reader to read and parse, which is more expensive than standard reader or NFC smart phone.
Das predicts that with the RFID becoming a low-cost alternative to Wi-Fi or Bluetooth systems, the market of battery assisted and passive RFID sensors will continue to grow.
Das said that printing temperature sensors and RFID antennas, flexible batteries and transistor circuits will also promote the popularity of RFID sensor solutions.
Passive sensor application