Trainable RF transceiver

• US 5,686,903 A
• Filed: 05/19/1995
• Issued: 11/11/1997
• Est. Priority Date: 05/19/1995
• Status: Expired due to Term

• Current Assignee: Gentex Corporation
• Original Assignee: Prince (Wellman Holdings, Inc.)
• Inventors: Dykema, Kurt A., Duckworth, Paul C.
• Primary Examiner(s): Holloway, III, Edwin C.
• Application Number:
  US08/445,142
• Time in Patent Office: 907 Days
• Field of Search: 340/825.22, 340/825.69, 340/825.72, 340/825.71, 340/825.31, 340/825.44, 341/176, 455/151.2, 455/115, 455/116, 455/255
• US Class Current: 340/5.25
• CPC Class Codes: E05F 15/77 using wireless control
• CPC Class Codes: E05Y 2400/664 by radio waves
• CPC Class Codes: E05Y 2800/00 Details, accessories and auxiliary operations not otherwise provided for
• CPC Class Codes: E05Y 2900/106 for garages
• CPC Class Codes: G08C 17/02 using a radio link
• CPC Class Codes: G08C 19/28 using pulse code
• CPC Class Codes: G08C 2201/20 Binding and programming of remote control devices
• CPC Class Codes: H04B 1/38 Transceivers, i.e. devices in which transmitter and receiver form a structural unit and in which at least one part is used for functions of transmitting and receiving

Abstract

A trainable transceiver for learning and transmitting an activation signal that includes an RF carrier frequency modulated with a code for remotely actuating a device, such as a garage door opener. In one embodiment, the trainable transceiver preferably includes a controller, a signal generator, and a dynamically tunable antenna having a variable impedance that may be selectively controlled in accordance with a carrier frequency of a received or transmitted activation signal. In another embodiment, the trainable transceiver preferably includes a phase-locked loop circuit for providing a frequency control voltage to a signal generator to selectively adjust the carrier frequency of the signal generator. In yet another embodiment, the trainable transceiver includes an amplifying circuit for selectively controlling the gain of a modulated radio frequency carrier signal received from the signal generator and for transmitting an amplified output signal to the remotely actuated device. In a further embodiment, the trainable transceiver includes a frequency table including a list of frequencies for remote transmitters known to transmit for only a short duration and the trainable transceiver first reads the short duration frequencies from the frequency table. Some embodiments will include one or more of these various features.

Claims

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

a controller operable in a learning and an operating mode, said controller receiving an activation signal in said learning mode and storing data corresponding to the radio frequency and code of the activation signal, and when in said operating mode, providing frequency control data representing the radio frequency of the received activation signal, and a code signal representing the code of the received activation signal;

a signal generator coupled to said controller for receiving said code signal from said controller, said signal generator having a frequency control terminal and responsive to a frequency control voltage applied to said frequency control terminal for transmitting a modulated radio frequency carrier signal including a code corresponding to said code signal; and

a phase-locked loop circuit coupled to said controller and to said signal generator for receiving said frequency control data and said code signal from said controller and for receiving said modulated radio frequency carrier signal from said signal generator, and providing a frequency control voltage to said frequency control terminal of said signal generator to selectively adjust the carrier frequency of said signal generator in accordance with said frequency control data in response to said code signal.

2. The trainable transceiver as defined in claim 1, wherein said phase-locked loop circuit includes:

a reference signal generator for generating a reference signal having a reference frequency;

a divide-by-N register having a control input coupled to said controller for receiving said frequency control data representing an integer value N, and coupled to said signal generator for dividing the carrier frequency of said modulated radio frequency carrier signal output by said signal generator by the integer N;

a phase/frequency detector coupled to said reference signal generator, said divide-by-N register, and said frequency control terminal of said signal generator, for comparing the reference frequency of said reference signal with a divided carrier frequency of a signal output from said divide-by-N register, and outputting a frequency control voltage to control the carrier frequency of said signal generator such that the divided carrier frequency is substantially the same as the divided reference frequency and the carrier frequency of said signal generator corresponds to the carrier frequency of the received activation signal; and

a control logic circuit coupled to the controller to receive said code signal and coupled between said phase/frequency detector and said signal generator for selectively connecting and disconnecting said phase/frequency detector from the signal generator in response to said code signal received from the controller.

3. The trainable transceiver as defined in claim 2, wherein said divide-by-N register includes a control terminal coupled to said controller for receiving said code signal and selectively suspending an output thereof in response to a logic level of said code signal.

4. The trainable transceiver as defined in claim 2, wherein said reference signal generator includes:

an oscillator for generating an output signal having a predetermined frequency; and

a divide-by-R register having a control input coupled to the controller for receiving data representing an integer value R, and coupled to said oscillator generator for dividing the output signal by the integer R to provide said reference signal.

5. A phase-locked loop circuit for use in a transmitter having a controller and a signal generator for generating a radio frequency carrier signal modulated with a code signal received from the controller for remotely activating a device, said phase-locked loop circuit comprising:

a reference signal generator for generating a reference signal having a reference frequency;

a divide-by-N register having a control input for receiving data representing an integer value N, and a frequency signal input for dividing the frequency of a signal applied thereto by the integer N; and

a phase/frequency detector coupled to said reference signal generator and said divide-by-N register for comparing the reference frequency of said reference signal with a divided frequency of a signal output from said divide-by-N register, and providing a frequency control signal to an output terminal of said phase-locked loop circuit, wherein the frequency value represented by the frequency control signal is varied in response to the comparison of the reference frequency with the divided frequency.

6. The phase-locked loop circuit as defined in claim 5 and further including a control logic circuit for coupling to a controller for receiving a code signal and coupled to said phase/frequency detector for selectively connecting and disconnecting said phase/frequency detector from said output terminal of said phase-locked loop circuit.

7. The phase-locked loop circuit as defined in claim 5, wherein said divide-by-N register includes a control terminal for coupling to a controller for receiving a code signal and selectively suspending an output thereof in response to the code signal.

8. The phase-locked loop circuit as defined in claim 5, wherein said reference signal generator includes a divide-by-R register having a control input for coupling to a controller for receiving data representing an integer value R, and a signal input for coupling to an oscillator for receiving a signal having a predetermined frequency and dividing the signal received from the oscillator by the integer R to provide said reference signal.

9. The phase-locked loop circuit as defined in claim 8, wherein said divide-by-N register and said divide-by-R register each include a control terminal for receiving a code signal and selectively suspending an output thereof in response to a logic level of the code signal.

10. The phase-locked loop circuit as defined in claim 5 and further including:

a switching circuit coupled to said phase/frequency detector for selectively connecting said output terminal of said phase-locked loop circuit to an open circuit, ground, or a positive voltage in response to said control signal from said phase/frequency detector.

12. The phase-locked loop circuit as defined in claim 10 and further including a control logic circuit for coupling to a controller for receiving a code signal and coupled to said phase/frequency detector and to said switching circuit for selectively connecting and disconnecting said phase/frequency detector from said switching circuit in response to the code signal received from the controller.

13. The phase-locked loop circuit as defined in claim 5, wherein the phase-locked loop circuit is an integrated circuit including a substrate, and wherein said reference signal generator, said divide-by-N register, and said phase/frequency detector are formed on said substrate.

11. The phase-locked loop circuit as defined in claim I0, wherein said switching circuit includes a tri-state switch having a high logic output state, a ground output state, and a high impedance output state.

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

a controller operable in a learning and an operating mode, said controller receiving an activation signal in said learning mode for storing data corresponding to the radio frequency and code of the activation signal, and in said operating mode, providing frequency control data representing the radio frequency of the received activation signal, and a code signal representing the code of the received activation signal;

a signal generator coupled to said controller for receiving said code signal from said controller and for transmitting a modulated radio frequency carrier signal including a code corresponding to said code signal, said signal generator having a frequency control terminal, wherein said modulated radio frequency carrier signal has a carrier frequency corresponding to a frequency control voltage applied to said frequency control terminal; and

a phase-locked loop circuit including;

a reference signal generator for generating a reference signal having a reference frequency,

a divide-by-N register having a control input coupled to said controller for receiving said frequency control data including a value N, and coupled to said signal generator for dividing the carrier frequency of said modulated radio frequency carrier signal output by said signal generator by N, and

a phase/frequency detector coupled to said reference signal generator, said divide-by-N register, and said frequency control terminal of said signal generator, for comparing the reference frequency of said reference signal with a divided carrier frequency of a signal output from said divide-by-N register, and outputting a frequency control voltage to control the carrier frequency of said signal generator such that the divided carrier frequency is substantially the same as the reference frequency and the carrier frequency of said signal generator corresponds to the carrier frequency of the received activation signal, wherein the voltage level of the frequency control voltage is varied in response to the comparison of the reference frequency with the divided carrier frequency.

15. The trainable transceiver as defined in claim 14, wherein said phase-locked loop further includes a low pass filter, wherein said signal generator is a voltage controlled oscillator and said low pass filter is coupled between said phase/frequency detector and the frequency control terminal of said voltage controlled oscillator for maintaining and supplying the frequency control voltage to the frequency control terminal.

16. The trainable transceiver as defined in claim 15, wherein said phase-locked loop further includes a switching circuit coupled to said phase/frequency detector and said low pass filter, for selectively increasing, maintaining, or decreasing the frequency control voltage provided by said low pass filter to said voltage controlled oscillator in response to an output from said phase/frequency detector.

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

a receiver for receiving an activation signal from a remote transmitter and outputting a code contained in the received activation signal, the received activation signal having any frequency falling within in a predetermined frequency band of at least 200 MHz;

a controller coupled to said receiver and operable in a learning and an operating mode, said controller receiving the code of the received activation signal in said learning mode for storing data corresponding to the RF carrier frequency and code of the activation signal, and in said operating mode, providing a gain control signal and output data, which identifies the RF carder frequency and code of the received activation signal;

a signal generator coupled to said controller, for receiving said output data for outputting a modulated radio frequency carrier signal related to the received activation signal; and

an amplifying circuit including a variable gain amplifier coupled to said signal generator and to said controller, for receiving said gain control signal from said controller and selectively controlling the gain of the modulated radio frequency carrier signal received from said signal generator in response to said gain control signal, and for transmitting an amplified output signal to the device, wherein said amplifying circuit further includes a coupling circuit coupled to an output of said variable gain amplifier for filtering harmonic components from the amplified output of said variable gain amplifier.

18. A method using a trainable transceiver, for learning and transmitting an activation signal that remotely actuates a device, comprising the steps of:

receiving an activation signal in a learning mode, the received activation signal having any frequency falling within in a predetermined frequency band of at least 200 MHz;

generating and storing radio frequency control data, which indicates a detected radio frequency carrier of the received activation signal;

generating gain control data, which indicates a gain level;

generating an output signal having a radio frequency carrier corresponding to that of the received activation signal;

selectively amplifying the output signal to a level controlled by the gain control data;

filtering harmonic components from the amplified output signal; and

transmitting the amplified and filtered output signal to the device.

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

a controller operable in a learning and an operating mode, said controller receiving an activation signal in said learning mode for storing data corresponding to the RF carrier frequency and code of the activation signal, and, in said operating mode, providing a gain control signal and output data, which identifies the RF carrier frequency and code of the received activation signal, the received activation signal having any frequency falling within the band of from about 220 MHz to about 440 MHz;

an integrated circuit including

a substrate,

a signal generator formed on said substrate and coupled to said controller, for receiving said output data and for outputting a modulated radio frequency carrier signal corresponding to the received activation signal, and

a variable gain amplifier formed on said substrate and coupled to said signal generator and to said controller, for receiving the gain control signal from said controller, for selectively amplifying said modulated radio frequency carrier signal received from said signal generator to a level controlled by the gain control signal, and for transmitting an amplified output signal to the device; and

a coupling circuit coupled to an output of said variable gain amplifier for filtering harmonic components from the amplified output of said variable gain amplifier.

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

a dynamically tumble antenna for and transmitting a modulated radio frequency carrier signal having a carrier frequency selected from a range of frequencies covering at least the range of 200 to 400 MHz, said dynamically tunable antenna having a control input and a tunable element such that the resonant frequency of said antenna can be varied in response to antenna control data applied to said control input to vary the filtering characteristics of said dynamically tunable antenna to provide a pass band substantially centered about the carrier frequency of said modulated radio frequency carrier signal;

a controller coupled to said dynamically tunable antenna and operable in a learning and an operating mode, said controller receiving an activation signal in said learning mode and storing data corresponding to the radio frequency and code of the activation signal, and when in the operating mode, providing antenna control data to said control input of said dynamically tunable antenna in order to selectively control the resonance frequency of said dynamically tunable antenna, generating a modulated radio frequency carrier signal, which corresponds to the received activation signal, and providing a gain control signal; and

an amplifying circuit, coupled to said controller for receiving the gain control signal, selectively controlling the gain of the modulated radio frequency carrier signal received from said controller to a level controlled by the gain control signal, and coupled to said dynamically tunable antenna for providing an amplified output signal to said dynamically tunable antenna for transmission to the device,

wherein, during said operating mode, said controller selects and outputs antenna control data corresponding to the radio frequency identified in the output data supplied to said signal generator such that said dynamically tunable antenna filters harmonic frequency components from said modulated radio frequency carrier signal generated by said signal generator.

21. The trainable transceiver as defined in claim 20 and further comprising:

a prompting circuit coupled to said controller for prompting an operator to cause the remote transmitter to retransmit its activation signal if the activation signal ceases before training is complete.

22. A trainable transceiver for receiving an activation signal that includes a radio frequency carrier modulated with a code and teaming characteristics of the activation signal for subsequently transmitting a signal having the same characteristics for remotely actuating a device, said trainable transceiver comprising:

a dynamically tunable antenna for receiving an activation signal and transmitting a modulated radio frequency carrier signal, said dynamically tunable antenna having a control input and a tunable element such that the resonance frequency of said antenna can be varied in response to antenna control data applied to said control input;

a controller coupled to said dynamically tunable antenna and operable in a learning and an operating mode, said controller receiving the activation signal while executing a training sequence in said learning mode and storing data corresponding to the radio frequency and code of the activation signal, and when in said operating mode, providing antenna control data to said control input of said dynamically tunable antenna in order to selectively control the resonance frequency of said dynamically tunable antenna, and for transmitting a modulated radio frequency carrier signal, which corresponds to the received activation signal, from said dynamically tunable antenna; and

a prompting circuit coupled to said controller for prompting an operator to cause the remote transmitter to retransmit its activation signal if the activation signal ceases before training is complete,

wherein, if the activation signal ceases before training is complete, said controller interrupts the training sequence and signals the prompting circuit to prompt the operator to cause the remote transmitter to retransmit its activation signal, and when the activation signal is retransmitted and received;

said controller resumes execution of the training sequence from a position in the training sequence at which the training sequence was interrupted.

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

a dynamically tunable antenna for receiving an activation signal and transmitting a modulated radio frequency carrier signal, said dynamically tunable antenna having a control input and a tunable element such that the resonance frequency of said antenna can be varied in response to antenna control data applied to said control input;

a controller coupled to said dynamically tunable antenna and operable in a learning and an operating mode, said controller receiving the activation signal in said learning mode and storing data corresponding to the radio frequency and code of the activation signal, and when in said operating mode, providing antenna control data to said control input of said dynamically tunable antenna in order to selectively control the resonance frequency of said dynamically tunable antenna, and for providing frequency control data representing the radio frequency of the received activation signal, and a code signal representing the code of the received activation signal;

a signal generator coupled to said controller for receiving said code signal from said controller, said signal generator having a frequency control terminal and responsive to a frequency control voltage applied to said frequency control terminal for transmitting a modulated radio frequency carrier signal including a code corresponding to said code signal; and

a phase-locked loop circuit coupled to said controller and to said signal generator for receiving said frequency control data and said code signal from said controller and for receiving said modulated radio frequency carrier signal from said signal generator, and providing a frequency control voltage to said frequency control terminal of said signal generator to selectively adjust the carrier frequency of said signal generator in accordance with said frequency control data in response to said code signal.

24. The trainable transceiver as defined in claim 23 and further comprising:

a prompting circuit coupled to said controller for prompting an operator to cause the remote transmitter to retransmit its activation signal if the activation signal ceases before training is complete.

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

a controller operable in a learning and an operating mode, said controller receiving an activation signal in said learning mode and storing data corresponding to the radio frequency and code of the activation signal, and when in said operating mode, providing a gain control signal, providing frequency control data representing the radio frequency of the received activation signal, and a code signal representing the code of the received activation signal;

a signal generator coupled to said controller for receiving said code signal from said controller, said signal generator having a frequency control terminal and responsive to a frequency control voltage applied to said frequency control terminal for generating a modulated radio frequency carrier signal including a code corresponding to said code signal;

a phase-locked loop circuit coupled to said controller and to said signal generator for receiving said frequency control data and said code data from said controller and for receiving said modulated radio frequency carrier signal from said signal generator, and providing a frequency control voltage to said frequency control terminal of said signal generator to selectively adjust the carrier frequency of said signal generator in accordance with said frequency control data in response to said code signal; and

an amplifying circuit, coupled to said controller for receiving the gain control signal, and coupled to said signal generator for selectively controlling the gain of the modulated radio frequency carrier signal received from said signal generator to a level controlled by the gain control signal, and for transmitting an amplified output signal to the device.

26. The trainable transceiver as defined in claim 25 and further comprising:

a prompting circuit coupled to said controller for prompting an operator to cause the remote transmitter to retransmit its activation signal if the activation signal ceases before training is complete.

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

a controller operable in a learning and an operating mode, said controller receiving an activation signal while executing a training sequence in said learning mode and storing data corresponding to the radio frequency and code of the activation signal, and when in said operating mode, providing .frequency control data representing the radio frequency of the received activation signal, and a code signal representing the code of the received activation signal;

a signal generator coupled to said controller for receiving said code signal from said controller, said signal generator having a frequency control terminal and responsive to a frequency control voltage applied to said frequency control terminal for generating a modulated radio frequency carrier signal including a code corresponding to said code signal;

a phase-locked loop circuit coupled to said controller and to said signal generator for receiving said frequency control data from said controller and for receiving said modulated radio frequency carrier signal from said signal generator, and providing a frequency control voltage to said frequency control terminal of said signal generator to selectively adjust the carrier frequency of said signal generator in accordance with said frequency control data; and

a prompting circuit coupled to said controller for prompting an operator to cause the remote transmitter to retransmit its activation signal if the activation signal ceases before training is complete,

wherein, if the activation signal ceases before training is complete, said controller interrupts the training sequence and signals the prompting circuit to prompt the operator to cause the remote transmitter to retransmit its activation signal, and when the activation signal is retransmitted and received, said controller resumes execution of the training sequence from a position in the training sequence at which the training sequence was interrupted.

28. A trainable transceiver for receiving an activation signal that includes a radio frequency carrier modulated with a code and teaming characteristics of the activation signal for subsequently transmitting a signal having the same characteristics for remotely actuating a device, said trainable transceiver comprising:

a dynamically tunable antenna for receiving an activation signal and transmitting a modulated radio frequency carrier signal, said dynamically tunable antenna having a control input and a tunable element such that the resonance frequency of said antenna can be varied in response to antenna control data applied to said control input;

a controller coupled to said dynamically tunable antenna and operable in a learning and an operating mode, said controller receiving the activation signal in said learning mode and storing data corresponding to the radio frequency and code of the activation signal, and when in said operating mode, providing antenna control data to said control input of said dynamically tunable antenna in order to selectively control the resonance frequency of said dynamically tunable antenna, providing a gain control signal, and for providing frequency control data representing the radio frequency of the received activation signal, and a code signal representing the code of the received activation signal;

a signal generator coupled to said controller for receiving said code signal from said controller, said signal generator having a frequency control terminal and responsive to a frequency control voltage applied to said frequency control terminal for transmitting a modulated radio frequency carrier signal including a code corresponding to said code signal;

a phase-locked loop circuit coupled to said controller and to said signal generator for receiving said frequency control data and said code signal from said controller and for receiving said modulated radio frequency carrier signal from said signal generator, and providing a frequency control voltage to said frequency control terminal of said signal generator to selectively adjust the carrier frequency of said signal generator in accordance with said frequency control data in response to said control signal; and

an amplifying circuit, coupled to said controller for receiving the gain control signal, and coupled to said signal generator for selectively controlling the gain of the modulated radio frequency carrier signal received from said signal generator to a level controlled by the gain control signal, and for transmitting an amplified output signal to the device.

29. The trainable transceiver as defined in claim 28 and further comprising:

a prompting circuit coupled to said controller for prompting an operator to cause the remote transmitter to retransmit its activation signal if the activation signal ceases before training is complete.

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

a memory for storing a frequency table including a first list of carrier frequencies for activation signals transmitted from remote transmitters that are known to transmit an activation signal of a duration shorter than that of most other activation signals; and

a controller coupled to said memory and operable in a learning and an operating mode, when in the learning mode, said controller receiving an activation signal, sequentially reading frequencies from the first list in said frequency table until a frequency is read from the first list that corresponds to a carrier frequency of the received activation signal, and storing frequency control data representing the frequency read from the frequency table that corresponds to the carrier frequency of received activation signal, and when in the operating mode, said controller providing the frequency control dam and a code signal representing the code of the received activation signal;

a signal generator coupled to said controller for receiving said code signal from said controller, said signal generator having a frequency control terminal and responsive to a frequency control voltage applied to said frequency control terminal for transmitting a modulated radio frequency carrier signal including a code corresponding to said code signal; and

a phase-locked loop circuit coupled to said controller and to said signal generator for receiving said frequency control data from said controller and for receiving said modulated radio frequency carrier signal from said signal generator, and providing a frequency control voltage to said frequency control terminal of said signal generator to selectively adjust the carrier frequency of said signal generator in accordance with said frequency control data.