Protocol management method for a passive RF identification device which can harvest power from different power sources

A protocol management method for a passive RF identification device which is arranged for harvesting power from a first reader sending a first interrogation field at a first frequency and from an independent second reader sending a second interrogation field at a second frequency different from the first frequency, this identification device having a first interface arranged to carry out a first communication protocol with the first reader and a second interface to carry out a second communication protocol with the second reader, this identification device comprising a power generator arranged for allowing the second reader to partially or fully power supply this identification device while the first interface is in an active state and the first communication protocol is executed and for allowing the first reader to partially or fully power supply this identification device while the second interface is in an active state and the second communication protocol is executed;

• wherein the identification device needs from the power generator at least a first determined power level for the execution of the first communication protocol and at least a second determined power level for the execution of the second communication protocol;
• wherein the identification device comprises a first field detector for the first interrogation field, which is at least activated during an execution of the first communication protocol to watch for the reception of this first interrogation field, and a second field detector for the second interrogation field, which is at least activated during an execution of the second communication protocol to watch for the reception of this second interrogation field;
• wherein, if during the execution of any communication protocol among the first and second communication protocols the reception of the corresponding first or second interrogation field is no more detected by the corresponding first or second field detector while the power provided by the power generator remains equal or superior to the corresponding first or second determined power level, then this communication protocol is stopped and the identification device enters a Standby state with respect to this communication protocol, this Standby state being a state in which the power provided by the power generator remains equal or superior to the corresponding first or second determined power level;
• and wherein, when the identification device is in said Standby state, said corresponding first or second field detector continues to watch for the reception of said corresponding first or second interrogation field in order to detect if this corresponding first or second interrogation field is again received by the identification device and, if this is the case, to trigger a restart of said any communication protocol.