For a project I need a NFC chip as a communication interface to a mobile phone. It would be ok to communicate directly with the phone or to write to a MIFARE Classic tag which is then read by the phone.
Due to software design reasons, it has to be the PN532 chip.
For functional prototyping I used an Arduino Uno and a PN532 breakout board which worked very well.
I would immediately use such boards as they are, but unfortunately the antenna is too big for my use case. The antenna's dimensions must not exceed 20mm x 60mm.
The problem is that I have no background in the RFID/NFC technology, especially in designing custom antennas.
Therefore, I would really appreciate any tips,
(1) if there are ready-to-use antennas that are compatible with the PN532 chip and just have to be connected/soldered to it or
(2) if there are any breakout-boards available in my required dimensions (I did not find any) or
(3) if there is a way to reuse existing components (e.g. parts of such breakout boards, and just replace antenna) to build a new module to overcome my lack of knowledge.
Thank you very much!