Patent ID: 7286041

Claim:
A system of communication between an interrogator unit and a plurality of transponders, whereby the interrogator unit detects a start of sending signal from a transponder and then modifies its interrogation signal so as to maintain the other transponders in a watching state, whereby the silent transponders interpret the modification of the interrogation signal as an extended silence command, and the detected transponder continues its sending despite the modification of the interrogation signal, and wherein, after identification of the detected transponder, the interrogator unit, on the one hand, again modifies its interrogation signal so as to extend the watching state of the silent transponders and, sends a command to the identified transponder, the silent transponders again interpreting the modification of the interrogation signal as an extended silence request, and, at the end of sending its identifier, the detected transponder goes into a listening mode for a given duration during which it interprets and then executes the command sent by the interrogator unit.