Remote keyless entry system for a vehicle and a method of controlling a vehicle function by the same

• US 7,724,125 B2
• Filed: 09/28/2006
• Issued: 05/25/2010
• Est. Priority Date: 09/28/2006
• Status: Expired due to Fees

• Current Assignee: Lear Corporation
• Original Assignee: Lear Corporation
• Inventors: Nantz, John S., Ghabra, Riad, King, Ronald O., Tang, Tom Q.
• Primary Examiner(s): Zimmerman; Brian A
• Assistant Examiner(s): YANG, JAMES J
• Application Number:
  US11/536,290
• Publication Number:
  US 20080088411A1
• Time in Patent Office: 1,335 Days
• Field of Search: 340/825, 340 51- 52, 340 56- 567, 307 101- 102, 375/225
• US Class Current: 340/5.64
• CPC Class Codes: B60R 25/24 using electronic identifiers containing a code not memorised by the user
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 30/18054 at stand still, e.g. engine in idling state hill holding B60W30/18118
• CPC Class Codes: B60W 30/192 Mitigating problems related to power-up or power-down of the driveline, e.g. start-up of a cold engine
• CPC Class Codes: G07C 2009/00198 the keyless data carrier having more than one limited data transmission ranges
• CPC Class Codes: G07C 2009/00793 by Hertzian waves
• CPC Class Codes: G07C 9/00182 operated with unidirectional data transmission between data carrier and locks
• CPC Class Codes: G08C 17/02 using a radio link

Abstract

A remote unit for a keyless entry system for a vehicle. The remote unit comprising a controller configured to generate a command signal in response to a user input. The command signal comprising a first command message and a substantially similar second command message. The first command message comprises a first low data rate portion and the second command message comprises a high data rate portion. The remote unit further comprising a transmitter configured to transmit the command.

Claims

1. A remote unit for a keyless entry system, the remote unit comprising:

a controller configured to generate a command signal for transmission during a transmission period in response to a user input, the command signal comprising a first command message and a second command message, wherein the first command message comprises first and second high power, low data rate portions having data indicative of a function corresponding to the user input and the second command message comprises a low power, high data rate portion having data indicative of the function corresponding to the user input;

wherein the first low data rate portion has a first transmission length within the transmission period, the second low data rate portion has a second transmission length within the transmission period, and the high data rate portion has a third transmission length within the transmission period;

wherein the data rate portions are arranged in the command signal such that the first low data rate portion precedes the high data rate portion and the high data rate portion precedes the second low data rate portion;

wherein the power and transmission lengths of the data rate portions are matched such that an average strength of the command signal is lower than a first threshold and such that a peak strength of the command signal is lower than the sum of the average strength of the command signal and a second threshold greater than the first threshold; and

a transmitter configured to transmit the command signal.

2. The remote unit according to claim 1 wherein the first low data rate portion has a transmission data rate in the range of approximately 500 to 2K bits/second and the high data rate portion has a transmission data rate in the range of approximately 5K and 20K bits/second.

3. The remote unit according to claim 1 wherein the user input corresponds to actuation of a manually-activated control element.

4. The remote unit according to claim 1 wherein the high data rate portion has a power transmission in the range of approximately 60 to 74 dBμ

V/m and the first low data rate portion has a power transmission in the range of approximately 78 to 95 dBμ

V/m.

5. A vehicle-mounted base unit for a keyless entry system, the vehicle-mounted base unit comprising:

a receiver configured to receive a command signal corresponding to a user input, the command signal comprising a first command message and a second command message, wherein the first command message comprises first and second high power, low data rate portions having data indicative of a vehicle function and the second command message comprises a lower power, high data rate portion having data indicative of the vehicle function;

wherein the first low data rate portion has a first transmission length within a transmission period of the command signal, the second low data rate portion has a second transmission length within the transmission period, and the high data rate portion has a third transmission length within the transmission period;

wherein the data rate portions are arranged in the command signal such that the first low data rate portion entirely precedes the high data rate portion and the high data rate portion entirely precedes the second low data rate portion;

wherein the power and transmission lengths of the data rate portions are matched such that an average strength of the command signal is lower than a first threshold and such that a peak strength of the command signal is lower than the sum of the average strength of the command signal and a second threshold greater than the first threshold; and

a controller configured to control the vehicle function in response to the command signal.

6. The vehicle-mounted base unit according to claim 5 wherein the first low data rate portion has a transmission data rate in the range of approximately 500 to 2K bits/second and the high data rate portion has a transmission data rate in the range of approximately 5K and 20K bits/second.

7. The vehicle-mounted base unit according to claim 5 wherein the user input corresponds to actuation of a manually-activated control element.

8. The vehicle-mounted base unit according to claim 5 wherein the high data rate portion has a power transmission in the range of approximately 60 to 74 dBμ

V/m and the first low data rate portion has a power transmission in the range of approximately 78 to 95 dBμ

V/m.

9. A keyless entry system for a vehicle, the keyless entry system comprising:

a remote unit configured to transmit a command signal during a transmission period in response to a user input, the command signal comprising a first command message and a second command message, wherein the first command message comprises first and second high power, low data rate portions having data indicative of a vehicle function and the second command message comprises a low power, high data rate portion having data indicative of the vehicle function;

wherein the first low data rate portion has a first transmission length within the transmission period, the second low data rate portion has a second transmission length within the transmission period, and the high data rate portion has a third transmission length within the transmission period;

wherein the data rate portions are arranged in the command signal such that the first low data rate portion precedes the high data rate portion and the high data rate portion precedes the second low data rate portion;

wherein the power and transmission lengths of the data rate portions are matched such that an average strength of the command signal is lower than a first threshold and such that a peak strength of the command signal is lower than the sum of the average strength of the command signal and a second threshold greater than the first threshold; and

a vehicle-mounted base unit configured to receive the command signal and to control the vehicle function in response to the command signal.

10. The keyless entry system according to claim 9 wherein the first low data rate portion has a transmission data rate in the range of approximately 500 to 2K bits/second and the high data rate portion has a transmission data rate in the range of approximately 5K and 20K bits/second.

11. The keyless entry system according to claim 9 wherein the user input corresponds to actuation of a manually-activated control element.

12. The keyless entry system according to claim 9 wherein the high data rate portion has a power transmission in the range of approximately 60 to 74 dBμ

V/m and the first low data rate portion has a power transmission in the range of approximately 78 to 95 dBμ

V/m.

13. The keyless entry system according to claim 9 wherein the first command message is received by the vehicle-mounted base unit when the remote unit transmits the command signal within 500 m.

14. The keyless entry system according to claim 9 wherein the first low data rate portion initiates the receiver.