A method for communication in ultra-wide bandwidth RFID systems comprising generating through a transceiver device an interrogation signal, composed of at least a sequence of equally time spaced pulses with period (T3), transmitting said signal to at least one RFID identification device which generates a response signal and transmits it back to said transceiver device, said method further comprising coding said interrogation signal according to a numerical coding sequence, generating said response signal by varying, in each period (T3) of said pulse sequence of the interrogation signal, the polarity of pulses using said numerical coding sequence. An apparatus for communication in ultra -wide bandwidth RFID systems comprising a transceiver device (1,101) and a RFID identification device (11), suitable for communicating each other, said RFID identification device (11) comprises a backscatter modulator (12) suitable for modulating a signal reflected by an antenna (18) of the identification device RFID.