Keyless security system

• US 6,326,885 B1
• Filed: 05/11/1995
• Issued: 12/04/2001
• Est. Priority Date: 05/20/1994
• Status: Expired due to Term

• Current Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Original Assignee: Alpine Electronics Incorporated (Alps Alpine Co., Ltd.)
• Inventors: Togashi, Kazuyuki
• Primary Examiner(s): Lieu, Julie
• Application Number:
  US08/439,082
• Time in Patent Office: 2,399 Days
• Field of Search: 340/426, 340/539, 340/825.69, 340/825.72, 340/531, 340/534, 307/10.2, 455/38.1, 455/38.2, 455/38.3, 455/99, 455/66
• US Class Current: 340/426.17
• CPC Class Codes: B60R 25/1003 Alarm systems characterised by arm or disarm features
• CPC Class Codes: B60R 25/24 using electronic identifiers containing a code not memorised by the user
• 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

Abstract

A keyless security system which has eliminated the need for providing a vehicle-mounted receiver with an electric field detector, thereby achieving a simpler construction with resultant lower cost. The keyless security system is equipped with a portable transmitter for transmitting a remote control signal for locking and unlocking a vehicular door lock mechanism and a vehicle-mounted receiver which has a signal receiver for receiving the remote control signal, a signal processing unit for processing the remote control signal, and a control unit for monitoring each section of the vehicle and also for controlling the entire system. The control unit and the signal receiver are placed periodically in an activated condition and a standby condition. When the control unit detects the electric field of a received remote control signal, the control unit and the signal receiver are placed in a continuously activated condition. The remote control signal includes data information and idling information which precedes the data information and which is composed of bits of only 1 or 0. The idling information of the remote control signal received by the signal receiver is supplied to the control unit which then detects the electric field of the received remote control signal in accordance with the idling information.

Claims

1. A keyless security system for a vehicle, the keyless security system comprising:

a portable transmitter for transmitting a predetermined remote control signal which contains idling information, wherein said idling information is composed of a plurality of digital bits comprising only one of logical one and logical zero information; and

a signal receiver for receiving said remote control signal, said signal receiver including;

a signal processing unit for processing said received remote control signal; and

a control unit for controlling a receptive state of said signal receiver in response to the processed remote control signal, and for monitoring the active condition of at least one sensor mounted on said vehicle;

wherein said control unit detects a transmission of said remote control signal from said portable transmitter by identifying the idling information supplied from said signal processing unit.

2. A keyless security system according to claim 1, wherein the remote control signal from said portable transmitter is composed of at least data information and said idling information, and wherein the idling information precedes the data information.

3. A keyless security system according to claim 1, wherein said signal receiver further comprises means for receiving at least an FM remote control signal.

4. A keyless security system according to claim 1, wherein said control unit is connected to receive activation signals from a plurality of sensors including a door sensor for detecting an opened door, a motion sensor for detecting the motion of the vehicle, a shock sensor for detecting a shock applied to the vehicle, and a glass sensor for detecting a broken window, and wherein the control unit issues an audible alarm when at least one activation signal is received, indicating that at least one of said sensors has been activated.

5. A keyless security system comprising:

a portable transmitter for transmitting a predetermined remote control signal which contains idling information and data information, wherein the idling information precedes the data information; and

a vehicle-mounted receiver including;

a signal receiver for receiving said remote control signal;

a signal processing unit for processing the received remote control signal; and

a control unit for controlling a receptive state of said signal receiver in response to the processed remote control signal, and for monitoring the condition of at least one sensor mounted on the vehicle;

wherein said control unit and said signal receiver are placed periodically in either of an activated condition and a standby condition, and said control unit and said signal receiver are placed in a continuously activated condition when said control unit detects the idling information of the received remote control signal; and

wherein said idling information contained in the remote control signal received by said signal receiver is supplied to said control unit and said control unit detects a transmission of said remote control signal from the remote control unit by identifying the supplied idling information.

6. The keyless security system according to claim 5, wherein said idling information is composed of digital bits comprising only one of logical one and logical zero information.

7. The keyless security system according to claim 5, wherein said signal receiver further comprises means for receiving at least an FM remote control signal.

8. A keyless security system according to claim 5, wherein said control unit is connected to receive activation signals from a plurality of sensors including a door sensor for detecting an opened door, a motion sensor for detecting the motion of the vehicle, a shock sensor for detecting a shock applied to the vehicle, and a glass sensor for detecting a broken window and the control unit issues an audible alarm when at least one activation signal is received, indicating that at least one of said sensors has been activated.

9. A keyless security system comprising:

a portable transmitter for transmitting a predetermined remote control signal which contains idling information; and

the vehicle-mounted receiver including;

a signal receiver for receiving said remote control signal;

a signal processing unit for processing the received remote control signal; and

a control unit for controlling a receptive state of said signal receiver in response to the processed remote control signal, and for monitoring the condition of at least one sensor mounted on the vehicle;

wherein said control unit and said signal receiver are placed periodically in either of an activated condition and a standby condition, and said control unit and said signal receiver are continuously placed in the activated condition when said control unit detects a transmission of the received remote control signal;

wherein said signal processing unit includes a low-pass filter, the idling information of the remote control signal received by said signal receiver being supplied to said control unit via the low-pass filter of said signal processing unit, and said control unit detects a transmission of said remote control signal by identifying said idling information;

wherein the signal processing unit does not include an electric field detector.

10. A keyless security system according to claim 9, wherein said remote control signal from said portable transmitter is composed of at least data information and the idling information, and wherein the idling information precedes the data information.

11. The keyless security system according to claim 10, wherein said idling information is composed of Manchester-coded or SPL-coded bits comprising only one of logical one and logical zero information.

12. The keyless security system according to claim 9, wherein said low-pass filter in said signal processing unit has a cutoff frequency which is substantially higher than the transmission frequency band of said idling information.

13. The keyless security system according to claim 12, wherein said signal processing unit further includes a second low-pass filter having a second cutoff frequency which is slightly higher than the transmission frequency band of said idling information, said second low-pass filter being connected in parallel to the first low-pass filter having the cutoff frequency which is substantially higher than the transmission frequency band of said idling information.

14. The keyless security system according to claim 12, wherein said first and second low-pass filters have outputs thereof connected to waveform shaping circuits, thus forming a first cascade-connected circuit and a second cascade-connected circuit, respectively.

15. The keyless security system according to claim 14, wherein said first cascade-connected circuit isolates the data information and said second cascade-connected circuit isolates the idling information.

16. The keyless security system according to claim 9, wherein said signal receiver further comprises means for receiving at least the FM remote control signal.

17. The keyless security system according to claim 9, wherein said control unit detects a single Manchester-coded or SPL-coded bit in the idling information in order to identify said idling information.

18. A keyless security system according to claim 9, wherein said control unit is connected to receive activation signals from a plurality of sensors including the door sensor for detecting an opened door, the motion sensor for detecting the motion of the vehicle, the shock sensor for detecting a shock applied to the vehicle, and the glass sensor for detecting broken window and the control unit issues an audible alarm when at least one activation signal is received, indicating that at least one of said sensors has been activated.

19. A keyless security system for a vehicle, the keyless security system comprising:

a portable transmitter for transmitting a predetermined remote control signal which contains idling information and data information, wherein the idling information precedes the data information; and

a signal receiver for receiving said remote control signal, said signal receiver including;

a signal processing unit for receiving transmission signals and for generating a reception signal in response to the transmission signals;

a switch connected between a power supply and the signal processing unit; and

a control unit connected to the signal processing unit and to the switch, said control unit generating a control signal for controlling said switch to connect the power supply to the signal processing unit;

wherein said signal processing unit transmits a reception signal to said control unit only while the signal processing unit is connected to the power supply through the switch;

wherein said control unit periodically generates said control signal such that the signal processing unit generates a plurality of reception signals; and

wherein, in response to the presence of said idling information in one of the successive plurality of reception signals, said control unit continuously generates said control signal such that the data information of the received remote control signal is transmitted from the signal processing unit to the control unit.