A method and apparatus is disclosed for operating an RFID read/write unit
with transmitting signal suppression. The RFID read/write unit comprises
a radio frequency part including a transmitter and a receiver, and a
baseband part based on digital signal processing. The method involves
producing an amplitude and phase weighted copy of a transmitting signal,
namely a compensation signal, with the baseband part. After linear
modulation of the compensation signal, a resultant signal at an input of
the receiver is subtracted in an addition stage from a spurious coupling
signal. The transmitting signal has an auxiliary signal impressed upon a
carrier signal from the RFID read/write unit with a frequency offset fd,
for the purpose of processing without any DC voltage in the receiver
downstream of an RX converter. The input of the receiver comprises a
turn-on and turn-off attenuation element which protects the radio
frequency part.