Which is the best way to output max power?

[marittia]

Hello everyone,

I would really like to use the X-NUCLEO-NFC06A1 expansion board in order to transmit power wireless. I read that it should be able to transmit 1.6W of power.

At the moment I used the NFC06A1 available library to power up the board. In particular I called the rfalNfcInitialize(), rfalNfcDiscover() and rfalFieldOnAndStartGT(), functions.

This way I am able to see that the antennas are functioning properly, but i did some testing and it seems like i can only get very few mA from a receiving antenna.

Which is the best way to initialize the board in order to deliver maximum power (regarderless of circumstances)?

Thank you very much.

[Marcel Rossignol · Accepted solution]

Hello,

an output power of around 1.6W can be achieved. That´s correct.

But the efficiency of the power transfer is not that high (typ. ~30%), which leads to max. transferred power of around 500mW!

The power transfer is depending on the matching network of the reader, the antenna design of reader and tag (Q & size) and the coupling factor between reader and tag antenna.

The current matching network of the Nucleo-board is not made for max. power transfer. This can be only done, if the receiving antenna is known.

How does your receiving antenna looks like?

Best regards,

Marcel

[marittia]

Thanks for your answer Marcel.

I didn't know that the max power transfer could only reach about 30% of the transmitted power.

At the moment I am using the NFC04A1 as receiver antenna, but I also tried different ones, such as rectangular 25x20mm and R25mm and R35mm pcb antennas. In all of my tries the NFC04A1 seems to be the better option at the moment.

On which type of receiving antenna can I possibly reach the max power transfer?

Thanks again for your time.

Best Regards,

Mariano