초록 ▼

An apparatus ( 10, 240, 300 ) includes a signpost ( 11, 241-256, 322, 612, 623, 626-628, 652, 661, 682, 686, 703 ) which transmits signpost signals ( 24 ) to a tag ( 12, 271-275, 301-316, 395-397, 616-618, 641-643, 653, 656-657, 662-664, 679, 708, 711 ), which in turn transmits beacon signals ( 72 )

An apparatus ( 10, 240, 300 ) includes a signpost ( 11, 241-256, 322, 612, 623, 626-628, 652, 661, 682, 686, 703 ) which transmits signpost signals ( 24 ) to a tag ( 12, 271-275, 301-316, 395-397, 616-618, 641-643, 653, 656-657, 662-664, 679, 708, 711 ), which in turn transmits beacon signals ( 72 ) to a reader ( 13, 261, 319, 521-530 ). One of the signpost and tag is mounted on an item to be tracked. A control system ( 14, 500 ) is responsive to the reader, and can cause the signpost to vary the signpost signal in a manner which varies at least one operational characteristic of the tag, such as a transmission rate, a transmission power, a tag identification code, a password, or an encryption code, or which shifts the tag between a normal operational mode and a low power operational mode in which its transmitter is disabled.

대표청구항 ▼

1. An apparatus comprising a tag having circuitry which includes:a receiver section operable to receive wireless signpost signals that each include a signpost code; anda transmitter section operable to transmit wireless beacon signals which each include a beacon code associated with said tag, said t

1. An apparatus comprising a tag having circuitry which includes:a receiver section operable to receive wireless signpost signals that each include a signpost code; anda transmitter section operable to transmit wireless beacon signals which each include a beacon code associated with said tag, said transmitter section being responsive to receipt by said receiver section of a respective said signpost signal for including in at least one said beacon signal the signpost code from the received signpost signal;wherein said signpost signals include a command portion, and wherein said tag is responsive to said command portion of a respective said signpost signal received by said tag for effecting a control function within said tag. 2. An apparatus according to claim 1, wherein said control function includes changing a transmit power of said beacon signals. 3. An apparatus according to claim 1, wherein said control function includes placing said tag into one of a normal operational mode and a restricted operational mode, said transmitter section being respectively enabled and disabled in said normal and restricted operational modes. 4. An apparatus according to claim 3, wherein said tag consumes less power in said restricted operational mode. 5. An apparatus according to claim 3, wherein said tag automatically enters said restricted operational mode in the absence of receipt by said tag of any said signpost signal for a predetermined time interval. 6. An apparatus according to claim 1, wherein said control function includes changing a rate of transmission of said beacon signals by said transmission section of said tag. 7. An apparatus according to claim 1, wherein said control function includes changing an operational parameter of said tag. 8. An apparatus according to claim 7, wherein said operational parameter is said beacon code of said tag. 9. An apparatus according to claim 7, wherein said operational parameter is an informational field other than said beacon code which is included in said beacon signals. 10. An apparatus according to claim 7, wherein said operational parameter is one of a password and an encryption code used in association with transmission and reception of at least one of said signpost signals and beacon signals. 11. An apparatus according to claim 1, including:a signpost which transmits said wireless signpost signals;a control system having a reader which receives said beacon signals; anda communication link which facilitates communication between said signpost and said control system, said control system being operable to send instructions to said signpost through said communication link which influence said signpost signals transmitted by said signpost. 12. An apparatus according to claim 11, wherein said instructions sent through said communication link include instructions which control what said signpost uses for said command portion of said signpost signals. 13. A method comprising the steps of:receiving in a receiver section of a tag wireless signpost signals that each include a signpost code and a command portion;transmitting from a transmitter section of said tag wireless beacon signals which each include a beacon code associated with said tag, said transmitting step including the step of causing said transmitter section to be responsive to receipt by said receiver section of a respective said signpost signal for including in at least one said beacon signal the signpost code from the received signpost signal; andeffecting a control function within said tag in response to said command portion of a respective said signpost signal received by said tag. 14. A method according to claim 13, wherein said step of effecting said control function includes the step of changing a transmit power of said beacon signals. 15. A method according to claim 13, wherein said step of effecting said control function includes the step of placing said tag into one of a normal operational mode and a restricted operational mode , said transmitter section being respectively enabled and disabled in said normal and restricted operational modes. 16. A method according to claim 15, including the step of causing said tag to operate in a manner which consumes less power when said tag is in said restricted operational mode. 17. A method according to claim 15, including the step of causing said tag to automatically enter said restricted operational mode in the absence of receipt by said tag of any said signpost signal for a predetermined time interval. 18. A method according to claim 13, wherein said step of effecting said control function includes the step of changing a rate of transmission of said beacon signals by said transmission section of said tag. 19. A method according to claim 13, wherein said step of effecting said control function includes the step of changing an operational parameter of said tag. 20. A method according to claim 19, including the step of selecting said beacon code of said tag as said operational parameter. 21. A method according to claim 19, including the step of selecting as said operational parameter an informational field other than said beacon code which is included in said beacon signals. 22. A method according to claim 19, including the step of selecting as said operational parameter one of a password and an encryption code used in association with transmission and reception of at least one of said signpost signals and beacon signals. 23. A method according to claim 13, including the steps of:transmitting said signpost signals from a signpost which is separate from said tag;receiving said beacon signals in a reader which is a part of a control system separate from said tag;providing a communication link between said control system and said signpost; andsending from said control system to said signpost through said communication link instructions which influence said signpost signals transmitted by said signpost. 24. A method according to claim 23, including the step of causing said signpost to vary what said signpost uses for said command portion of said signpost signals as a function of said instructions sent through said communication link.