Method and Device for Radiofrequency Communication

1 . A radiofrequency (RF) communication method according to which a communication can be set up between a reader and an RF device at least over a medium distance and over a short distance, the short distance communication being set up using an RF-ID transponder and an antenna, the medium distance communication being set up by the reader sending a command signal to the RF-ID transponder in order to switch at least one microcontroller and a transceiver from a passive state to an active state, said microcontroller sending to the reader, via said transceiver, a reply message comprising at least the identification of the RF device.

2 . The method according to claim 1 , said reply message also comprising data for synchronizing the medium distance communication of said reader with the RF device.

3 . The method according to claim 1 , which also involves a long distance communication, in which a wake-up signal transmitted by a clock wakes up said microcontroller, which then communicates with said reader via said transceiver.

4 . The method according to claim 3 , in which, after having received said wake-up clock signal, said microcontroller checks whether the RF device is already in short or medium distance operation and, if this is the case, said microcontroller decides to set up the long range operation communication at a later time.

5 . The method according to claim 3 , in which a long distance communication is divided into several transmission-reception messages and in which, between two successive messages, said microcontroller checks that said reader is not transmitting any query signals in RF-ID mode.

6 . The method according to claim 1 , in which, at the end of each communication with said reader, the RF device is no longer electrically powered apart from a clock.

7 . A device for radiofrequency (RF) communication with a reader, the device being able to communicate at least over a short distance and over a medium distance and comprising an antenna and an RF-ID transponder connected to said antenna, the device also including a programmed microcontroller, a transceiver connected to said microcontroller and an electrical power source, the short distance communication being carried out using said antenna and said RF-ID transponder said RF-ID transponder being arranged to detect a command signal sent by said reader and to connect at least said microcontroller to said power supply source when said command signal is detected, so that the medium distance communication can take place via said microcontroller and said transceiver.

8 . The device according to claim 7 , the device including a switch coupled to, on the one hand, said antenna and, on the other hand, to said transceiver and to said RF-ID transponder, said switch being able to take two positions, a short distance communication position for which the antenna is coupled to said RF-ID transponder and a medium or long range communication position for which the antenna is coupled to the transceiver.

9 . The device according to claim 7 , the device including a frequency selective coupler capable of connecting simultaneously the antenna to the RF-ID transponder and to the transceiver, in two separate frequency ranges.

10 . The device according to claim 7 , the device including at least one sensor connected to said microcontroller.

11 . A radiofrequency (RF) communication method according to which a communication can be set up between a reader and an RF device at least over a medium distance and over a short distance, comprising:

using an RF-ID transponder and an antenna to set up the short distance communication;

sending a command signal from the reader to the RF-ID transponder the medium distance communication being set up by the reader sending a command signal to the RF-ID transponder in order to switch at least one microcontroller and a transceiver from a passive state to an active state, said microcontroller sending to the reader, via said transceiver, a reply message comprising at least the identification of the RF device.

12 . The method according to claim 11 , said reply message also comprising data for synchronizing the medium distance communication of said reader with the RF device.

13 . The method according to claim 11 , which also involves a long distance communication, in which a wake-up signal transmitted by a clock wakes up said microcontroller, which then communicates with said reader via said transceiver.

14 . The method according to claim 13 , in which, after having received said wake-up clock signal, said microcontroller checks whether the RF device is already in short or medium distance operation and, if this is the case, said microcontroller decides to set up the long range operation communication at a later time.

15 . The method according to claim 13 , in which a long distance communication is divided into several transmission-reception messages and in which, between two successive messages, said microcontroller checks that said reader is not transmitting any query signals in RF-ID mode.

16 . The method according to claim 11 , in which, at the end of each communication with said reader, the RF device is no longer electrically powered apart from a clock.

17 . A device for radiofrequency (RF) communication with a reader, the device being able to communicate at least over a short distance and over a medium distance and comprising an antenna and an RF-ID transponder connected to said antenna, the device also including a programmed microcontroller, a transceiver connected to said microcontroller and an electrical power source, the short distance communication being carried out using said antenna and said RF-ID transponder said RF-ID transponder being arranged to detect a command signal sent by said reader, and to connect at least said microcontroller to said power supply source when said command signal is detected, so that the medium distance communication can take place via said microcontroller and said transceiver.

18 . The device according to claim 17 , the device including a switch coupled to, on the one hand, said antenna and, on the other hand, to said transceiver and to said RF-ID transponder, said switch being able to take two positions, a short distance communication position for which the antenna is coupled to said RF-ID transponder and a medium or long range communication position for which the antenna is coupled to the transceiver.

19 . The device according to claim 17 , the device including a frequency selective coupler capable of connecting simultaneously the antenna to the RF-ID transponder and to the transceiver, in two separate frequency ranges.

20 . The device according to claim 17 , the device including at least one sensor connected to said microcontroller.