RFID system with a 'smart' passive TAG at a range of about 40cm

[Olly]

I'm am looking to prototype an RFID system that involves communicating with a 'smart' passive TAG at a range of about 40cm. Which evaluation boards (reader and passive tag board) would be best suited for this application?

I'm am looking to prototype an RFID system that involves communicating with a 'smart' passive TAG at a range of about 40cm.

This 'smart' passive tag board would need to have a programmable microcontroller and be able to use energy harvesting to power the tag.

Which evaluation boards (reader and passive tag board) would be best suited for this application?

[Ulysses HERNIOSUS]

Hi Olly,

I think a system of ST25R3916(B) + ST25DVC might be able to achieve such. However the demo kits for our NFC readers are coming with antenna sizes which will not be able to achieve such range. Please look around this forum to find some information about range discussions, e.g. here.

At this link you will find some experiments done based on ST25R3911B but we actually recommend the newer ST25R3916(B) due to its improved sensitivity.

Best Regards, Ulysses

[Olly]

Hi Ulysses,

Thanks for your reply, the linked discussions were very useful.

I have the following setup:

• Reader: X-NUCLEO-NFC06A1 (with the ST25R3916)
  • Microcontroller connected to the Reader: NUCLEO-L476RG
• Tag: STEVAL-SMARTAG1

I am able to successfully read the SMARTAG1 at a range of about 9cm from the reader, and I have a few questions:

1) Is there any way to increase the read range without changing either of the antennas? (i.e. by increasing the ST25R3916 transmission power, increasing the receiver sensitivity, reducing the data rate, adding a metallic reflector back-plate etc.)

2) For our use case, we would need the Reader antenna to fit within a circle with a radius of about 5 cm. Would we be able to read a passive Tag at a range of 40 cm with a <5cm Reader antenna (with either HF or UHF RFID, or different antenna types)?

3) The NFC-V standard states a read range of up to 1m. Is this only possible with a huge antenna or can that kind of read range be achieved with a small/portable antenna size? (e.g. ~5cm reader antenna)

4) How would I go about measuring the power draw of the ST25R3916 on the X-NUCLEO-NFC06A1 breakout board? (Is there a jumper I can disconnect/trace I can cut in order to attach a scope/ammeter/Nordic Power Profiler Kit?)

Thanks for your help.

Kind Regards,

Olly

[Ulysses HERNIOSUS]

Hi Olly,

ad 1) Our ST25R3916 demos are built to make maximal usage of the chip and the connected antenna. I don't see ways of substantially improving the range.

ad 2) I think UHF (ST25RU3993) can do such.

ad 3) 1m read range is not possible with a 5cm antenna

ad 4) Please check the schematics available from st.com. If I recall correctly there is no place for placing a shunt / amperemeter. Likely the easiest is to bend away the supply pin on the Arduino connector and put it back in on top through an amperemeter.

BR, Ulysses