The VDC embedded hardware team received a very interesting briefing from RFMicron (Austin, Texas) on an IC component aimed at solving a problem seen with passive RFID tags. In addition to increasing the performance of the RFID tag, the new chip (called Magnus) actually allows the tag to perform additional functions and, as a result, we believe that this product has many potential M2M applications.
Here is a bit of background. Passive RFID tags do not contain any power source of their own. When stimulated by the correct RF signal, they chirp back data that is stored on or measured by the tag at that moment. Because a passive RFID tag is essentially using the received energy to transmit the return signal the tuning between the tag electronics and antenna have to be near perfect. One thing that can interfere with a passive RFID tag’s performance is moisture. The new Magnus chip enables the passive RFID tag to adjust for moisture to maintain optimal operation. That, by itself, is significant because it allows objects that are in sub-optimal conditions (e.g. wet) to be monitored wirelessly at greater distances. As a result M2M applications could be deployed over extremely long periods of time without needing any power source on the individual assets. What made this new component really interesting is that moisture data from the component could be transmitted by the tag along with the stored ID number. In our opinion, passive RFID tags with this component could be a key piece in an M2M optimized agricultural operation. Here is how it would work:
VDC’s View of M2M Enabled Agriculture using Passive RFID Moisture Detection
1.) During planting process, the farm equipment inserts the RFID tags at given intervals along with the seeds. The embedded computer on the farm equipment logs and transmits the tag’s ID number and GPS location data to the cloud.
2.) As farm equipment pass over the fields, the RFID reader scans the sensors and the embedded computer collects the data. This allows for the creation of a economical irrigation plan. VDC pictures this as being similar to ink-jet printers in precision as opposed to pumping water and spraying for fixed intervals.
3.) Data from the moisture sensors can be retained in the cloud to confirm that optimal irrigation was maintained.
4.) At harvest time, data on crop yields and quality are collected and sent to the cloud.
5.) The cloud stored data can be used for many purposes that benefit several agricultural stakeholders including:
6.) At the end of the process, the farmer tills over the field without having to worry about recovering sensors or their connectivity infrastructure.
What happens to the RFID tags after that? We have to assume that most of the tags would survive for several years but they would no longer have precise location or soil depth. Although, it is possible that the tags could be recovered for future use, the cost of doing so would likely exceed their cost of approximately $1 per unit. In future growing seasons, any data received from RFID tags deployed with earlier crops would be ignored.
The connected-farm is only one of many possible M2M applications for passive RFID sensor tags. For example, the moisture detecting RFID tags could be installed inside tanks at regular intervals to detect liquid levels. Other physical properties such as pressure or temperature could be included to increase functionality. The M2M possibilities are endless.