Developing RFID sensor software requires you to understand the differences between standard tags and sensors tags. Learn about these in this post.
RFID technology is well known for its capability to uniquely identify items, wirelessly, without requiring batteries on the RFID tag.
When looked at it from an outsider point of view, the key here will be ‘how the hell do they manage to convey a wireless communication without a battery?’ While it is true that’s a key, from the user perspective it is a fact, nothing you need to worry about. You set the system correctly, hit a button in the software that the manufacturer shared with you and off you go.
However, that reader software you are using has all the power and, unluckily, the limitations of your system. Although reader manufacturers have made a great job developing software for your RFID tracking systems, the same software will not help you at all when trying to develop solutions with RFID sensors.
Why RFID sensors are a different breed
Battery-free RFID sensors – such as temperature, soil moisture, ambient light, LEDs, etc. – are based on EPC C1G2 commands. Basically any reader out in the market complying with the standard should work with sensor tags.
However, there are a couple of big differences between sensor tags and identification tags:
- Sensor tags have a higher power requirement. You need to make sure the reader sends enough power so the sensor can work.
- Sensors require specific commands in order to work properly. Notice that I didn’t say custom commands but specific. With this I mean sensors may need to receive commands to set up their working mode before they start measuring – this means the RFID tag needs to WRITE on the sensor before reading – or read from a specific user memory address a specific number of words.
What does this mean for companies with software development capabilities?
Companies that are able to develop software will have to clearly understand the APIs that the reader manufacturer provides them with.
In order to transfer as much energy as possible from the reader to the tag you will have to understand not just how to set up the maximum output power from the reader but also how to maximize the duty cycle – special mention to minimum idle times between commands (they are different from API to API).
You will also have to deal with the correct sequence of commands. This will depend on the application you want to develop but the idea is that you bear in mind that sensors will require specific commands to run. The RFID tag acts as a bridge to the sensor so even if the commands are the same – such as WRITE or READ – the memory addresses will be dependent on the sensor being used.
‘What if I cannot develop SW?’
Our best recommendation here is to try and find a software that gives you everything you need.
To date, RFID sensors are not a common thing so you will probably not find a software that works for your application. I would at least recommend you work with someone that can offer you the possibility of running some testing without you needing to develop software.
Entering into software development without having tested the technology can lead you to high investments only to learn later on that the technology is not providing you with the read range, sensor accuracy, device size or any other characteristic your application required.
For more information about read range in RFID systems download the ‘The essential guide to developing RFID sensor software‘ free eBook.