Transponder arrangement

• US 6,411,212 B1
• Filed: 07/21/1999
• Issued: 06/25/2002
• Est. Priority Date: 07/21/1998
• Status: Expired due to Term

• Current Assignee: Daimler AG (Mercedes-Benz Group AG)
• Original Assignee: Daimler Chrysler Company LLC (Stellantis NV)
• Inventors: Hecht, Johannes, Kollbach, Dietbert
• Primary Examiner(s): LA, ANH V
• Application Number:
  US09/357,852
• Time in Patent Office: 1,070 Days
• Field of Search: 340/505, 340/825.34, 340/426, 340/572.1, 340/572.5, 340/572.7, 340/539, 340/825.69, 340/825.31, 340/10.1, 340/10.2, 340/10.3, 340/10.34, 307/10.4, 307/10.5, 307/10.2, 307/10.42, 307/112, 307/113, 342/44, 342/51, 604/20
• US Class Current: 340/572.1
• CPC Class Codes: G06K 19/0701 at least one of the integrated circuit chips comprising an arrangement for power management
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 7/10178 including auxiliary means for focusing, repeating or boosting the electromagnetic interrogation field comparable booster antennas integrated on the record carrier itself G06K19/07794
• CPC Class Codes: H04B 5/00 Near-field transmission systems, e.g. inductive or capacitive transmission systems
• CPC Class Codes: H04B 5/26 using coils
• CPC Class Codes: H04B 5/45 Transponders
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

For a transponder arrangement having a transponder arranged on an object, in order to achieve longer ranges than would be possible with a purely field-supplied response mode, the transponder is provided with a chargeable electrical energy store. An inductive supply of energy from a pump circuit situated on the object is used to hold the energy store in a charged state. The transponder arrangement can advantageously be interrogated not only in the active mode now made possible, but also in a passive mode which is known per se and is supplied with power purely by the interrogation field.

Claims

1. A transponder arrangement for an object having a dedicated power source to operate the object, comprising:

a transponder arranged on said object and configured to communicate with an external interrogation unit, the transponder including a chargeable electrical energy store from which electrical power is drawn for the transponder at least for a transmission operating mode;

a pump circuit arranged on said object and coupled to said dedicated power source used to operate said object, the pump circuit producing a charging signal used to transfer energy during a charging process via an inductive coupling to the chargeable electrical energy store of the transponder without using an external field of the interrogation unit;

a pump circuit coupling coil connected to the pump circuit;

a transponder coupling coil coupled to the transponder, wherein the inductive coupling used to transfer energy between the pump circuit and the chargeable electrical energy store is carried out via the pump coupling coil and the transponder coupling coil.

2. The arrangement according to claim 1, wherein the transponder coupling coil operates to both charge the energy store and to communicate with the external interrogation unit.

3. The arrangement according to claim 2, further comprising an antenna loop associated with the object, wherein the transponder coupling coil is inductively coupled with the antenna loop.

4. The arrangement according to claim 3, further comprising a transformer, the transformer coupling the transponder coupling coil with at least one of the pump coupling coil and the antenna loop.

5. The arrangement according to claim 1, wherein the pump circuit produces a charging signal and the transponder has an operating frequency or frequencies, a charging frequency of the pump circuit charging signal being different from the operating frequency or frequencies of the transponder.

6. The arrangement according to claim 5, further comprising a frequency-selector in the transponder for blocking a signal path to the energy store of signals at the operating frequencies of the transponder.

7. The arrangement according to claim 1, further comprising the external interrogation unit which generates an operating frequency for transponder operation, wherein a charging frequency of a charging signal produced by the pump circuit is the same as the operating frequency of the external interrogation unit.

8. The arrangement according to claim 1, wherein the energy transfer in a charging process of the energy store is operated only as required.

9. The arrangement according to claim 8, wherein the pump circuit queries a charge state of the energy store at regular intervals and conducts the energy transfer to the energy store when required.

10. The arrangement according to claim 8, wherein the transponder transmits a charge request signal to the pump circuit if a charge state of the energy store falls below a predefined threshold.

11. The arrangement according to claim 9, wherein the transponder transmits a charge request signal to the pump circuit if a charge state of the energy store falls below a predefined threshold.

12. The arrangement according to claim 1, wherein the energy transfer occurs regularly independent of any charge state requirements of the energy store.

13. The arrangement according to claim 12, wherein in the regular charging process, a length of the charging process is shorter than a time interval between successive charging processes.

14. The arrangement according to claim 1, wherein in addition to the transmission operating mode supplied with energy by the energy store, a passive operating mode of the transponder is supplied with energy by a field from the external interrogation unit.

15. The arrangement according to claim 1, further comprising an encrypted data communication device arranged in the transponder.

16. The arrangement according to claim 15, wherein the device is a cryptoprocessor.

17. The arrangement according to claim 1, wherein the transponder operates in a simultaneous transmission/reception mode.

18. The arrangement according to claim 17, wherein a transmission frequency of the transponder is derived from a frequency of an interrogation signal.

19. The arrangement according to claim 1, wherein the transponder includes transmission and reception circuitry, said circuitry being of different technologies and operating in different frequency bands.

20. The arrangement according to claim 1, further comprising a wake-up circuit arranged in the transponder.

21. The arrangement according to claim 1, wherein the chargeable electrical energy store is one of an accumulator and capacitor.

22. The arrangement according to claim 1, wherein the chargeable electrical energy store is a solid-electrolyte capacitor.

23. A method of operating an arrangement having a transponder with a chargeable electrical energy store on an object having a dedicated power source to operate the object, the method comprising the acts of:

supplying the transponder with electrical power from the electrical energy store at least for a transmission operating mode in which the transponder communicates with an external interrogation unit;

charging the electrical energy store via an inductive coupling of energy from a pump circuit coupleable to said dedicated power source used to operate said object using a pump coupling coil and a transponder coupling coil, without using an external field of the interrogation unit.

24. The method according to claim 23, further comprising the act of operating the transponder coupling coil both for charging the energy store and for communicating with the external interrogation unit.

25. The method according to claim 23, further comprising the act of using a charging frequency of a charging signal of the pump circuit that is different from an operating frequency of the transponder.

26. The method according to claim 23, further comprising the act of blocking a signal path to the energy store for signals at operating frequencies of the transponder.

27. The method according to claim 23, further comprising the act of using a charging frequency of a charging signal of the pump circuit which is the same as an operating frequency of the external interrogation unit for externally interrogating the transponder.

28. The method according to claim 23, wherein the charging process further comprises the acts of:

querying a charge state of the energy store via the pump circuit at regular intervals; and

charging the energy store via the pump circuit based on results of the queries.

29. The method according to claim 23, wherein the charging process further comprises the act of transmitting a charge request signal from the transponder to the pump circuit if a charge state of the energy store falls below a predefined threshold value.

30. The method according to claim 23, further comprising the act of operating the charging process act at intervals having a length less than time intervals between successive charging processes.