Method for the at least temporary activation of bidirectional communication and transponder
View Patent ↗A method for the at least temporary activation of bidirectional communication between a transponder having a nonvolatile memory area and a base station, whereby the transponder in an at least partial mute state receives messages, but no information-related data from the nonvolatile memory area are transmitted and for activation a data stream is transmitted to the transponder by the base station, wherein the data stream for a transmission is linked with a symmetric password, the enable signal is extracted by the transponder with the symmetric password from the received data stream, and the transponder is activated at least temporarily after the enable signal has been verified as valid. The invention relates further to a transponder having means for carrying out this type of procedure.
1. A method, comprising:
receiving at a transponder, from a base station in response to the transponder communicating to the base station a signal indicating that the transponder is in at least a partial mute state, a message comprising a masked data stream encoded using a symmetric password stored at the transponder, the masked data stream comprising an enable signal for activating the transponder;
accessing, in response to receiving the message, the symmetric password stored at the transponder;
extracting the enable signal from the masked data stream using the symmetric password; and
transitioning from the at least a partial mute state to an active state if the enable signal extracted from the masked data stream corresponds to a valid enable signal.
2. The method of claim 1 , wherein the message further comprises an address pointer, the address pointer corresponding to a memory area of a nonvolatile memory of the transponder.
3. The method of claim 2 , wherein the symmetric password further comprises content of the memory area of the nonvolatile memory of the transponder corresponding to the address pointer.
4. The method of claim 1 , wherein the message is constructed using a select command of ISO/IEC-CD 18000-6C standard.
5. The method of claim 1 , wherein the message further comprises a bit counter.
6. The method of claim 1 , wherein the message further comprises one or more CRC bits.
7. The method of claim 1 , wherein the at least a partial mute state comprises a state in which the transponder, in response to a query message from the base station, transmits at least a random number to the base station.
8. The method of claim 1 , wherein the at least a partial mute state comprises a state in which the transponder, in response to a query message from the base station, does not transmit data to the base station temporarily.
9. The method of claim 1 , wherein the at least a partial mute state is one of a plurality of possible mute states for the transponder, a current mute state of the transponder being set using one or more control bits.
10. The method of claim 1 , further comprising updating one or more of the symmetric password and the enable signal.
11. The method of claim 1 , wherein at least part of the masked data stream is transmitted in an interleaving process by the base station.
12. A transponder, comprising:
a nonvolatile memory area;
a receiving unit configured to receive, from a base station in response to the transponder communicating to the base station a signal indicating that the transponder is in at least a partial mute state, a message comprising a masked data stream encoded using a symmetric password stored at the transponder, the masked data stream comprising an enable signal for activating the transponder; and
a control logic configured to:
access, in response to receiving the message, the symmetric password stored at the transponder;
extract the enable signal from the masked data stream using the symmetric password; and
transition from the at least a partial mute state to an active state if the enable signal extracted from the masked data stream corresponds to a valid enable signal.
13. The transponder of claim 12 , wherein the message further comprises an address pointer, the address pointer corresponding to a memory area of a nonvolatile memory of the transponder.
14. The transponder of claim 13 , wherein the symmetric password further comprises content of the memory area of the nonvolatile memory of the transponder corresponding to the address pointer.
15. The transponder of claim 12 , wherein the message is constructed using a select command of ISO/IEC-CD 18000-6C standard.
16. The transponder of claim 12 , wherein the at least a partial mute state comprises a state in which the transponder, in response to a query message from the base station, transmits at least a random number to the base station.
17. The transponder of claim 12 , wherein the at least a partial mute state comprises a state in which the transponder, in response to a query message from the base station, does not transmit data to the base station temporarily.
18. The transponder of claim 12 , wherein the at least a partial mute state is one of a plurality of possible mute states for the transponder, a current mute state of the transponder being set using one or more control bits.
19. The transponder of claim 12 , wherein at least part of the masked data stream is transmitted in an interleaving process by the base station.
20. A base station, comprising:
a memory; and
one or more processors configured to:
receive from a transponder a signal indicating that the transponder is in at least a partial mute state;
determine to activate the transponder;
transmit, in response to determining to activate the transponder, a message comprising a masked data stream encoded using a symmetric password stored at the transponder, the masked data stream comprising an enable signal for activating the transponder;
the transponder being operable to:
receive the transmitted message;
access, in response to receiving the message, the symmetric password stored at the transponder;
extract the enable signal from the masked data stream using the symmetric password; and
transition from the at least a partial mute state to an active state if the enable signal extracted from the masked data stream corresponds to a valid enable signal.