Automobile keyless entry system having an RFID interrogator

• US 8,410,899 B2
• Filed: 02/09/2012
• Issued: 04/02/2013
• Est. Priority Date: 11/19/2008
• Status: Expired due to Fees

• Current Assignee: Greatbatch Limited (Greatbatch Incorporated)
• Original Assignee: Greatbatch Limited (Greatbatch Incorporated)
• Inventors: Stevenson, Robert A., Tyers, Geddes Frank, Frysz, Christine A.
• Primary Examiner(s): Mehmood, Jennifer
• Assistant Examiner(s): GIRMA, FEKADESELASS
• Application Number:
  US13/369,728
• Publication Number:
  US 20120139702A1
• Time in Patent Office: 418 Days
• Field of Search: 340/5.61, 340/10.1
• US Class Current: 340/5.61
• CPC Class Codes: A61N 1/3718 Monitoring of or protection against external electromagnetic fields or currents
• CPC Class Codes: B60R 2325/105 Radio frequency identification data [RFID]
• CPC Class Codes: B60R 25/00 Fittings or systems for preventing or indicating unauthorised use or theft of vehicles locks for vehicles E05B77/00-E05B85/00
• 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 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10009 sensing by radiation using wavelengths larger than 0.1 mm, e.g. radio-waves or microwaves
• CPC Class Codes: G06K 7/10217 parameter settings controlling the transmission power of the interrogator
• CPC Class Codes: G08B 13/248 EAS system combined with another detection technology, e.g. dual EAS and video or other presence detection system
• CPC Class Codes: G16H 40/63 for local operation

Abstract

A keyless entry system for an automobile is described. The keyless entry system comprises a radio frequency identification (RFID) tag that has been programmed to selectively unlock an automobile when the RFID tag is within a predetermined distance and, optionally, to lock the automobile when the RFID is outside the predetermined distance. An interrogator housed on or within the automobile comprises an actuatable RF signal generator for transmitting an electromagnetic signal and a time-out circuit. Regardless whether the programmed RFID tag is detected, or not, the RF signal generator transmits a first electromagnetic signal having a first limited total continuous transmit time, followed by an interim period of a defined length where the time-out circuit renders the interrogator incapable of transmitting the electromagnetic signal, followed by the RF signal generator transmitting a second electromagnetic signal having a second limited total continuous transmit time.

Claims

1. A keyless entry system for an automobile, the keyless entry system comprising:

a) a radio frequency identification (RFID) tag that has been programmed to selectively unlock an automobile when the RFID tag is within a predetermined distance and to lock the automobile when the RFID is outside the predetermined distance;

b) an actuatable RF signal generator for transmitting an electromagnetic signal, wherein the RF signal generator is housed within or on the automobile; and

c) a time-out circuit, wherein regardless whether the programmed RFID tag is detected, or not, the RF signal generator transmits a first electromagnetic signal having a first limited total continuous transmit time, followed by an interim period of a defined length where the time-out circuit renders the interrogator incapable of transmitting the electromagnetic signal, followed by the RF signal generator transmitting a second electromagnetic signal having a second limited total continuous transmit time,

d) wherein no matter how frequently the RF signal generator is actuated by being within the predetermined distance of the RFID tag, the time-out circuit prevents the second and subsequent transmissions of the electromagnetic signal after a prior electromagnetic signal has been transmitted from the RF signal generator until the interim period of the defined length has expired.

2. The keyless entry system of claim 1 wherein the electromagnetic signal comprises an RFID communication signal.

3. The keyless entry system of claim 1 wherein the electromagnetic signal is selected from the group consisting of an RFID interrogation signal, an RFID tag search signal, an RFID test signal, an RFID read signal, and an RFID write signal.

4. The keyless entry system of claim 1 wherein the total continuous transmit time for each of the first, second and subsequent transmissions of the electromagnetic signal is no greater than five seconds.

5. The keyless entry system of claim 1 wherein the time-out circuit prevents transmission of the subsequent electromagnetic signal for two seconds or more.

6. The keyless entry system of claim 1 wherein the total continuous transmit time for each of the first, second and subsequent transmissions of the electromagnetic signal is 500 milliseconds or less.

7. The keyless entry system of claim 1 wherein the time-out circuit is programmable.

8. The keyless entry system of claim 1 wherein the electromagnetic signal comprises a modulated signal.

9. The keyless entry system of claim 1 wherein the RFID tag comprises a read-only or a readable/writable RFID tag.

10. The keyless entry system of claim 1 being communicable with a computer or a computer network.

11. The keyless entry system of claim 1 wherein the RFID tag comprises an antenna and an electronic micro-chip electrically connected to the antenna.

12. The keyless entry system of claim 1 wherein the electromagnetic signal is transmittable in the LF or HF frequency range.

13. The keyless entry system of claim 1 including a switch for selectively actuating the RF signal generator and the time-out circuit.

14. The keyless entry system of claim 1 including means for changing retrievable information in the RFID tag.

15. The keyless entry system of claim 1 wherein after the automobile is unlocked, the interrogator is programmable to start the automobile'"'"'s ignition.

16. A keyless entry system for an automobile, the keyless entry system comprising:

a) a radio frequency identification (RFID) tag that has been programmed to selectively unlock an automobile when the RFID tag is within a predetermined distance and to lock the automobile when the RFID is outside the predetermined distance;

b) an interrogator, which comprises;

i) an actuatable RF signal generator for transmitting an electromagnetic signal, wherein the RF signal generator is housed within or on the automobile; and

ii) a time-out circuit, wherein regardless whether an RFID tag is detected, or not, the RF signal generator transmits a first electromagnetic signal having a first limited total continuous transmit time, followed by an interim period of a defined length where the time-out circuit renders the interrogator incapable of transmitting the electromagnetic signal, followed by the RF signal generator transmitting a second electromagnetic signal having a second limited total continuous transmit time,

iii) wherein no matter how frequently the RF signal generator is actuated by being within the predetermined distance of the RFID tag, the time-out circuit prevents the second and subsequent transmissions of the electromagnetic signal after a prior electromagnetic signal has been transmitted from the RF signal generator until the interim period of the defined length has expired; and

c) means for changing retrievable information in the RFID tag, the retrievable information corresponding to changes in characteristics of an automobile.

17. The keyless entry system of claim 16 wherein the electromagnetic signal is selected from the group consisting of an RFID interrogation signal, an RFID tag search signal, an RFID test signal, an RFID read signal, and an RFID write signal.

18. The keyless entry system of claim 16 wherein the total continuous transmit time for each of the first, second and subsequent transmissions of the electromagnetic signal is no greater than five seconds.

19. The keyless entry system of claim 16 wherein the time-out circuit prevents transmission of the subsequent electromagnetic signal for two seconds or more.

20. The keyless entry system of claim 16 wherein the total continuous transmit time for each of the first, second and subsequent transmissions of the electromagnetic signal is 500 milliseconds or less.

21. The keyless entry system of claim 16 wherein the time-out circuit is programmable.

22. The keyless entry system of claim 16 comprising a read-only or a read/write device.

23. The keyless entry system of claim 16 being communicable with a computer or a computer network.

24. The keyless entry system of claim 16 wherein after the automobile is unlocked, the interrogator is programmable to start the automobile'"'"'s ignition.