Trainable transmitter and receiver

• US 5,583,485 A
• Filed: 06/05/1995
• Issued: 12/10/1996
• Est. Priority Date: 12/05/1988
• Status: Expired due to Term

• Current Assignee: Gentex Corporation
• Original Assignee: Prince (Wellman Holdings, Inc.)
• Inventors: Zeinstra, Mark L., Van Lente, Paul S., Suman, Michael J., DeVree, William S.
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US08/461,653
• Time in Patent Office: 554 Days
• Field of Search: 340/525, 340/425.5, 340/825.69, 340/825.72, 340/825.22, 340/825.5, 455/151.1, 455/151.2, 455/184.1
• US Class Current: 340/525
• CPC Class Codes: B60R 1/04 mounted inside vehicle B60R1/025, B60R1/08 take precedence
• CPC Class Codes: B60R 1/088 using a cell of electrically changeable optical characteristic, e.g. liquid-crystal or electrochromic mirrors
• CPC Class Codes: B60R 1/12 Mirror assemblies combined with other articles, e.g. clocks
• CPC Class Codes: B60R 1/1207 with lamps; with turn indicators
• CPC Class Codes: B60R 2001/1215 with information displays
• CPC Class Codes: B60R 2001/1223 with sensors or transducers
• CPC Class Codes: B60R 2001/123 with thermometers
• CPC Class Codes: B60R 2001/1284 with communication systems other than radio-receivers, e.g. keyless entry systems, navigation systems; with anti-collision systems
• CPC Class Codes: G07C 2009/00261 the keyless data carrier having more than one function
• CPC Class Codes: G07C 2009/00793 by Hertzian waves
• CPC Class Codes: G07C 2009/00928 for garage doors
• CPC Class Codes: G07C 9/00182 operated with unidirectional data transmission between data carrier and locks
• CPC Class Codes: G07C 9/00817 where the code of the lock can be programmed
• CPC Class Codes: G08C 2201/20 Binding and programming of remote control devices

Abstract

A vehicle structural accessory includes one or more electronic accessories. One electrical accessory which may be provided is an electronically trainable transmitter which is trainable to generate a control signal which will actuate a garage door opening mechanism. Another electronic accessory which may be included is an electronic compass. Yet another device is an electronically adjustable mirror having parameters set for each driver of a vehicle. The electronically adjustable rearview mirror and the electronically trainable garage door opener may be advantageously provided with a keyless entry system.

Claims

1. In a system including a trainable transmitter for transmitting an RF signal having predetermined learned characteristics corresponding to those of an RF activation signal received from a remote control transmitter and stored in a memory of the trainable transmitter, a receiver for coupling to the trainable transmitter comprising:

an antenna for receiving an RF activation signal from a remote control transmitter;

a signal generator having a frequency control terminal for receiving a frequency control signal and for generating a reference signal having a variable reference frequency related to said frequency control signal;

a demodulator coupled to said receiver and to an output of said signal generator for demodulating the received activation signal using said reference signal; and

a controller for coupling to the memory of the trainable transmitter, coupled to said demodulator for detecting the presence of a data code at an output of said demodulator, and coupled to said frequency control terminal of said signal generator for supplying said frequency control signal and changing the reference frequency of said reference signal until a data code is detected at the output of said demodulator, said controller identifying an RF carrier frequency of the received activation signal based upon the reference frequency at which a data signal was detected, and supplying the detected data signal and data representing the RF carrier frequency of the received activation signal to the memory of the trainable transmitter for storage therein for subsequent use by the trainable transmitter.

2. The receiver as defined in claim 1, wherein said demodulator includes:

a mixer having a first signal input terminal coupled to an output of said antenna for receiving the RF activation signal and having a second signal input terminal coupled to an output of said signal generator for receiving said reference signal, said mixer providing a signal having the data code of the activation signal modulated at a modulation frequency representing a difference between the reference frequency and the carrier frequency of the activation signal.

3. The receiver as defined in claim 2, wherein said demodulator further includes:

a filter having an input coupled to an output of said mixer for blocking all signals supplied to the filter input from said mixer except signals having a predetermined modulation frequency, said filter supplying the data code present in the received signal to said controller when the reference frequency and the carrier frequency of the activation signal have a predetermined relationship.

4. The receiver as defined in claim 1, and further including an operator actuated switch coupled to said controller for controlling the operational state of said controller between idle and training modes, said controller controlling said signal generator by supplying said frequency control signal to said frequency control terminal of said signal generator when in said training mode when said switch is actuated by an operator.

5. The receiver as defined in claim 1, wherein said signal generator includes:

a voltage controlled oscillator having a control voltage terminal and an output coupled to said demodulator for supplying said reference signal, said reference signal having a frequency related to a control voltage applied to said control voltage terminal; and

a frequency control loop circuit having said frequency control terminal coupled to said controller for receiving said frequency control signal, and coupled to said voltage control terminal for supplying said control voltage to said voltage controlled oscillator, said frequency control loop further includes an input for receiving an output signal having a stable reference frequency from a reference oscillator and an input for receiving the reference signal generated by said voltage controlled oscillator, said frequency control loop alters the frequency of the reference signal received from said voltage controlled oscillator in accordance with said frequency control signal received from said controller, compares the stable reference frequency of the output signal received from said reference oscillator with the altered frequency of the reference signal, and adjusts the control voltage supplied to said control voltage terminal of said voltage controlled oscillator until the adjusted frequency of the reference signal is the same as the stable reference frequency of said reference oscillator.

6. A trainable transmitter for use in a system including a receiver for receiving an RF activation signal from a remote control transmitter and identifying characteristics of the received RF activation signal including a carrier frequency and a data code, said trainable transmitter comprising:

a memory for receiving and storing the identified characteristics of the RF activation signal from the receiver;

a signal generator having a frequency control terminal for receiving a frequency control signal, wherein said signal generator generates and transmits a modulated RF output signal having a carrier frequency related to a frequency control signal supplied thereto; and

a controller coupled to said memory and to said frequency control terminal of said signal generator for reading and supplying the stored data code to a data input terminal of said signal generator and supplying the frequency control signal representing the stored frequency control data to said frequency control terminal of said signal generator such that the carrier frequency of the modulated RF output signal transmitted by said signal generator is the same as the identified carrier frequency of the RF activation signal.

7. The transmitter as defined in claim 6, and further including an operator actuated switch coupled to said controller for controlling the operational state of said controller between idle and transmitting modes, said controller controlling said signal generator by supplying said frequency control signal to said frequency control terminal of said signal generator and by supplying the stored data code to said data input terminal of said signal generator when in said transmitting mode when said switch is actuated by an operator.

8. The transmitter as defined in claim 6, wherein said signal generator includes:

an antenna;

a voltage controlled oscillator having a control voltage terminal, said data input terminal of said signal generator, and an output coupled to said antenna for transmitting the modulated RF output signal, the modulated RF output signal having a frequency related to a control voltage applied to said control voltage terminal; and

a frequency control loop circuit having said frequency control terminal coupled to said controller for receiving said frequency control signal, and coupled to said voltage control terminal for supplying said control voltage to said voltage controlled oscillator, wherein said frequency control loop further includes an input for receiving an output signal having a stable reference frequency from a reference oscillator and an input for receiving the modulated RF output signal generated by said voltage controlled oscillator;

wherein said frequency control loop alters the frequency of the modulated RF output signal received from said voltage controlled oscillator in accordance with said frequency control signal received from said controller, compares the stable reference frequency of the output signal received from said reference oscillator with the altered frequency of the modulated RF output signal, and adjusts the control voltage supplied to said control voltage terminal of said voltage controlled oscillator until the adjusted frequency of the modulated RF output signal is the same as the stable reference frequency of said reference oscillator.

9. A trainable system operable in a learning mode for receiving an activation signal that includes a radio frequency carrier modulated with a code and learning characteristics of the activation signal, and operable in an transmitting mode for subsequently transmitting a signal having the same characteristics for remotely actuating a device, said trainable system comprising:

an antenna for receiving an RF activation signal from a remote control transmitter;

reference signal generating means having a reference frequency control terminal for receiving a reference frequency control signal, for generating a reference signal having a variable reference frequency related to a reference frequency control signal supplied thereto;

a demodulator coupled to said antenna and to an output of said reference signal generating means for demodulating the received activation signal using said reference signal;

receiver control means coupled to said demodulator for detecting the presence of a data code at an output of said demodulator, and coupled to said reference frequency control terminal of said reference signal generating means for supplying said reference frequency control signal and changing the reference frequency of said reference signal until a data code is detected at the output of said demodulator, said receiver control means identifying an RF carrier frequency of the received activation signal based upon the reference frequency at which a data code was detected, and outputting the detected data code and frequency control data representing the RF carrier frequency of the received activation signal;

a memory adapted to be coupled to said receiver control means for receiving and storing said detected data code and frequency control data;

output signal generating means having an output frequency control terminal for receiving an output frequency control signal, for transmitting a modulated RF output signal having a carrier frequency related to the output frequency control signal supplied thereto; and

output control means coupled to said memory and to said output signal generating means for supplying the stored data code to a data input terminal of said output signal generating means and supplying an output frequency control signal representing the stored frequency control data to the output frequency control terminal of said output signal generating means such that the carrier frequency of the modulated RF output signal transmitted by said output signal generating means is the same as that of the activation signal received from the remote transmitter.

10. The trainable system as defined in claim 9, wherein said demodulator includes:

a mixer having a first signal input terminal coupled to an output of said antenna for receiving the RF activation signal and having a second signal input terminal coupled to an output of said reference signal generating means for receiving said reference signal, said mixer providing a signal having the data code of the activation signal modulated at a modulation frequency representing a difference between the reference frequency and the carrier frequency of the activation signal.

11. The trainable system as defined in claim 10, wherein said demodulator further includes:

a filter having an input coupled to an output of said mixer for blocking all signals supplied to the filter input from said mixer except signals having a predetermined modulation frequency, said filter supplying the data code present in the received signal to said receiver control means when the reference frequency and the carrier frequency of the activation signal have a predetermined relationship.

12. The trainable system as defined in claim 9, and further including an operator actuated switch coupled to said receiver control means for controlling the operational state of said receiver control means between idle and training modes, said receiver control means controlling said reference signal generating means by supplying said reference frequency control signal to said reference frequency control terminal of said reference signal generating means when in said training mode when said switch is actuated by an operator.

13. The trainable system as defined in claim 9, wherein said reference signal generating means includes:

a voltage controlled oscillator having a control voltage terminal and an output coupled to said demodulator for supplying said reference signal, said reference signal having a frequency related to a control voltage applied to said control voltage terminal; and

a frequency control loop circuit having said reference frequency control terminal coupled to said controller for receiving said reference frequency control signal, and coupled to said voltage control terminal for supplying said control voltage to said voltage controlled oscillator, wherein said frequency control loop further includes an input for receiving an output signal having a stable reference frequency from a reference oscillator and an input for receiving the reference signal generated by said voltage controlled oscillator; and

wherein said frequency control loop alters the frequency of the reference signal received from said voltage controlled oscillator in accordance with said frequency control signal received from said receiver control means, compares the stable reference frequency of the output signal received from said reference oscillator with the altered frequency of the reference signal, and adjusts the control voltage supplied to said control voltage terminal of said voltage controlled oscillator until the adjusted frequency of the reference signal is the same as the stable reference frequency of said reference oscillator.

14. The trainable system as defined in claim 9, and further including an operator actuated switch coupled to said output control means for controlling the operational state of said controller between idle and transmitting modes, said output control means controlling said output signal generating means by supplying said output frequency control signal to said output frequency control terminal of said output signal generating means and by supplying the stored data code to said data input terminal of said output signal generating means when in said transmitting mode when said switch is actuated by an operator.

15. The trainable system as defined in claim 9, wherein said output signal generating means includes:

a voltage controlled oscillator having a control voltage terminal, said data input terminal of said output signal generating means, and an output for transmitting the modulated RF output signal, the modulated RF output signal having a frequency related to a control voltage applied to said control voltage terminal; and

a frequency control loop circuit having said output frequency control terminal coupled to said output control means for receiving said frequency control signal, and coupled to said voltage control terminal for supplying said control voltage to said voltage controlled oscillator, said frequency control loop further includes an input for receiving an output signal having a stable reference frequency from a reference oscillator and an input for receiving the modulated RF output signal generated by said voltage controlled oscillator; and

wherein said frequency control loop changes the frequency of the modulated RF output signal received from said voltage controlled oscillator in accordance with said frequency control signal received from said output control means, compares the stable reference frequency of the output signal received from said reference oscillator with the altered frequency of the modulated RF output signal, and adjusts the control voltage supplied to said control voltage terminal of said voltage controlled oscillator until the adjusted frequency of the modulated RF output signal is the same as the stable reference frequency of said reference oscillator.

16. A trainable system operable in a learning mode for receiving an activation signal that includes a radio frequency carrier modulated with a code and learning characteristics of the activation signal, and operable in an transmitting mode for subsequently transmitting a signal having the same characteristics for remotely actuating a device, said trainable system comprising:

an antenna for receiving an RF activation signal from a remote control transmitter;

reference signal generating means having a reference frequency control terminal for receiving a reference frequency control signal, for generating a reference signal having a variable reference frequency related to a reference frequency control signal supplied thereto;

a demodulator coupled to said antenna and to an output of said reference signal generating means for demodulating the received activation signal using said reference signal, said demodulator including

a mixer having a first signal input terminal coupled to an output of said antenna for receiving the RF activation signal and having a second signal input terminal coupled to an output of said reference signal generating means for receiving said reference signal, said mixer providing a signal having the data code of the activation signal modulated at a modulation frequency representing a difference between the reference frequency and the carrier frequency of the activation signal,

a filter having an input coupled to an output of said mixer for blocking all signals supplied to the filter input from said mixer except signals having a predetermined modulation frequency, said filter outputting the data code present in the received signal when the reference frequency and the carrier frequency of the activation signal have a predetermined relationship;

receiver control means coupled to said filter for detecting the presence of a data code at an output of said filter, and coupled to said reference frequency control terminal of said reference signal generating means for supplying said reference frequency control signal and changing the reference frequency of said reference signal until a data code is detected at the output of said filter, said receiver control means identifying an RF carrier frequency of the received activation signal based upon the reference frequency at which a data code was detected, and outputting the detected data code and frequency control data representing the RF carrier frequency of the received activation signal;

a memory adapted to be coupled to said receiver control means for receiving and storing said detected data code and frequency control data;

output signal generating means having an output frequency control terminal for receiving an output frequency control signal, for transmitting a modulated RF output signal having a carrier frequency related to the output frequency control signal supplied thereto; and

output control means coupled to said memory and to said output signal generating means for supplying the stored data code to a data input terminal of said output signal generating means and supplying an output frequency control signal representing the stored frequency control data to the output frequency control terminal of said output signal generating means such that the carrier frequency of the modulated RF output signal transmitted by said output signal generating means is the same as that of the activation signal received from the remote transmitter.

17. The trainable system as defined in claim 16, and further including an operator actuated switch coupled to said receiver control means for controlling the operational state of said receiver control means between idle and training modes, said receiver control means controlling said reference signal generating means by supplying said reference frequency control signal to said reference frequency control terminal of said reference signal generating means when in said training mode when said switch is actuated by an operator.

18. The trainable system as defined in claim 16, and further including an operator actuated switch coupled to said output control means for controlling the operational state of said controller between idle and transmitting modes, said output control means controlling said output signal generating means by supplying said output frequency control signal to said output frequency control terminal of said output signal generating means and by supplying the stored data code to said data input terminal of said output signal generating means when in said transmitting mode when said switch is actuated by an operator.

19. The trainable system as defined in claim 16, wherein said output control means is coupled to an electronically adjustable mirror for control of the reflectivity thereof in response to output signals received from at least one ambient light sensor coupled to said output control means, said output control means also coupled to a compass circuit for receiving vehicle heading information and to a display for displaying the vehicle heading to occupants of the vehicle.