I am using the slrc610 to read a custom RFID tag in ISO/IEC 15693. The system is in a confined space with a reader antenna that is 5mm x 5mm and the tag is roughly the same size. The working distance is less than 1mm and the mechanical design is build such that the working distance is always the same. I want to find a way to measure the margin of the system performance and one though was to decrease the transmission power level until the tag was no longer readable. I have tried reducing the TxAmp register set_cw_amplitude (found in “SLRC610 High-performance ICODE frontend SLRC610 and SLRC610 plus – 227643” section 8.8.2), but it did not cause enough variation to be noticeable.
Is there any other way to reduce the transmitter voltage until reading is no longer possible? Or another method for measuring margin of the system?