Abstract:
A method of secure remote control by voice wherein the digitization and speech recognition functions are separated, which involves receiving an audible voice password in a remote controller, digitizing the voice password, and transmitting the digitized voice password and an ID from the controller to a base station. The method also includes confirming the ID and the password in the base station, receiving an audible voice command in the controller, and digitizing the command. The method still further includes transmitting the digitized command from the controller to the base station, confirming the command to indicate transmission of a desired control signal by the base station, and transmitting the control signal from the base station in response to the command.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation-in-part of U.S. patent application Ser. No. 09/420,670 filed Oct. 19, 1999 which claims the benefit of U.S. Provisional Patent Application serial No. 60/104,942 filed Oct. 20, 1998. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention relates generally to remote activation systems and, more particularly, to remote voice activation systems. 
     Many electronic interface control systems require a user initiated input. The user-initiated input may entail, but is not limited to, a keystroke, switch actuation, or a variable adjustment level output. For many applications these inputs are captured by electronic circuitry and transmitted from a remote location via electrical hardwire connections to a receiving device to initiate some operation or to transfer data. In other applications the user-initiated input is transmitted by a wireless communication method to the receiving device. The method of wireless communication can be RF, IR, or other wireless communication format. For example, a garage door opener is typically such a device. Other examples include, remote controls for audiovisual systems, remote activation devices for automobile anti-theft systems, remote door unlock devices for automobiles, remote engine start devices for automobiles, and many other similar examples. 
     The introduction of voice activation technology into electronic interface control systems that require a user initiated input is known for hardwired communication systems. These systems typically entail a power source, an analog audible sensing device (for sensing a user initiated audible command input), and an audio receiving device in electrical communication with an audio amplifier transmitting what is typically an analog audio signal via hardwire to a receiving device. The receiving device filters and digitizes the signal with an electronic audio filtering and digitizing circuit. In addition, the receiving device includes a speech recognition microchip with supporting electronic devicesl capturing the digitized audio signal and comparing the signal&#39;s electronic profile with signal profiles that have been previously stored. If the digitized signal matches a previously stored signal profile the signal is deemed valid and a control signal will be output from the voice recognition receiving device identifying a particular control command. Access to a hard wired interface can be easily controlled by conventional means such as physically restricting an area from unauthorized users. However, access to a remote control unit is less controllable because the remote is typically small and can be lost or misplaced. 
     Accordingly, a need exists for a secure remote voice activation system wherein a lost remote is not useable by a finder of the remote. 
     BRIEF SUMMARY OF THE INVENTION 
     A method of remotely generating a control signal prompted by an audible voice command includes transmitting an ID from a remote controller to a base station and confirming the ID. After receiving an audible voice password in the controller, the password is digitized and transmitted from the controller to the base station. The base station confirms the password and enables receipt of a digitized voice command if the password is valid. The method still further includes transmitting the digitized command from the controller to the base station, confirming the command to indicate transmission of a desired control signal by the base station, and transmitting the control signal from the base station in response to the command. Accordingly, if the controller is lost, a finder does not know the password and will not be able to use the remote. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a block diagram of a controller; 
     FIG. 2 is a schematic diagram of a circuit exemplifying one embodiment of the controller shown in FIG. 1; 
     FIG. 2A is an enlarged view of the switch mode power supply shown in FIG. 2; 
     FIG. 2B is an enlarged view of one portion of the audio output shown in FIG. 2; 
     FIG. 2C is an enlarged view of another portion of the audio output shown in FIG. 2; 
     FIG. 2D is an enlarged view of the CVSD unit shown in FIG. 2; 
     FIG. 2E is an enlarged view of the WTWR unit shown in FIG. 2; 
     FIG. 2F is an enlarged view of the micro-controller shown in FIG. 2; 
     FIG. 3 is a block diagram of a base station; 
     FIG. 4 is a schematic diagram of the power supply shown in FIG. 3; 
     FIG. 5 is a schematic diagram of a speech recognition unit exemplifying one embodiment of the speech recognition unit shown in FIG.  3 . 
     FIG. 5A is an enlarged view of the memory storage unit shown in FIG.  5 . 
     FIG. 5B is an enlarged view of the speech recognition chip shown in FIG.  5 . 
     FIG. 6 is a schematic diagram of an input/output connector exemplifying one embodiment of the serial bus interface shown in FIG. 3; 
     FIG. 7 is a schematic diagram of an audio amplifier exemplifying one embodiment of the amplifier shown in FIG. 3; 
     FIG. 8 is a schematic diagram of a receive and transmit module amplifier; 
     FIG. 8A is an enlarged view of the speech recognition unit shown in FIGS. 3 and 8. 
     FIG. 8B is an enlarged view of the WTWR shown in FIG. 8; 
     FIG. 8C is an enlarged view of a portion of the amplifier shown in FIG. 8; 
     FIG. 9 is a schematic diagram of a micro-controller; 
     FIG. 9A is an enlarged view of the micro-controller shown in FIG. 9; 
     FIG. 9B is an enlarged view of a communication interface; and 
     FIG. 10 is a block diagram of a remote voice activation system. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 is a block diagram of a controller  100  for one embodiment of a secure remote voice activation system (not shown in FIG.  1 ). Controller  100  includes a switch mode power supply  102  including a battery  104  and a switch or relay  106  having an open state (not shown) and a closed state (not shown). Controller  100  further includes a microphone input  108  electrically connected to a two stage filtered amplifier  110 . Amplifier  110  is electrically connected to a Continuously Variable Slope Delta-modulation modulator (CVSD)  112  which is electrically connected to an audio output device  114  and a micro-controller  116 . Micro-controller  116  is electrically connected to an acoustical wave transmitter/wave resonator  118  (WTWR) which is electrically connected to an antenna  120 . 
     During operation of controller  100 , a user (not shown) activates switch  102  and speaks into microphone  108  first giving a password and then issuing a voice command. Amplifier  110  amplifies both the password and the voice command. A continuously variable slope delta modulator (CVSD)  112  digitizes the amplified password and voice command, and then CVSD  112  encodes the digitized password and voice command. In one embodiment, CVSD  112  Manchester encodes the digitized password and voice command. WTWR  118  transmits the encoded digitized password and command utilizing antenna  120 . In an exemplary embodiment, the password and command are encrypted by micro-controller  116  before being encoded. Micro-controller  116  controls CVSD  112  and WTWR  118 , and, in an exemplary embodiment, when switch  106  is closed, micro-controller  116  uses antenna  120  and WTWR  118  to receive wireless signals in the range of 910 to 920 Megahertz (MHZ) and then searches for an encoded signal. In one embodiment, if a Manchester clock is derived from any signal received, then micro-controller  116  does not transmit any of the ID, the password, and the command. Accordingly, data collision between multiple controllers is avoided. 
     However, if no clock is derived from any signal received, then micro-controller  116  transmits the ID and the password and waits for confirmation from a base station that the ID and password are valid before sending the encoded digitized voice command to the base station. In one embodiment, the clock to be derived is a Manchester clock that recognizes a Manchester encoded signal. The base station confirms the ID by echoing back the micro-controller transmitted ID to micro-controller  116 . Upon receipt of the echoed back ID, micro-controller  116  transmits the command to the base station. In an alternative embodiment, micro-controller  116  transmits the ID and waits for a confirmation from a base station (not shown in FIG. 1) that the ID is a valid ID. Upon receiving the confirmation, micro-controller  116  transmits the encoded digitized password and command to the base station. In another embodiment, micro-controller  116  transmits the ID and, after receiving a confirmation signal, controller  100  emits an audible signal from audio output device  114 . The user hears the audible signal and says the password and command. It is to be understood that encoding other than Manchester encoding could be used with the above described system. 
     FIG. 2 is a schematic diagram of a circuit  200  exemplifying one embodiment of controller  100  (shown in FIG.  1 ). Circuit  200  includes a power supply circuit  202  including a battery  204  and a push-to-talk (PTT) switch  206 . Circuit  200  further includes a microphone input  208  electrically connected to an amplifier  210  that is electrically connected to a CVSD unit  212 . Unit  212  is electrically connected to an audio output  214  and a micro-controller unit  216  that is electrically connected to a WTWR unit  218 . WTWR unit  218  is further electrically connected to an antenna  220 . 
     Since circuit  200  is an exemplary embodiment of controller  100  (shown in FIG.  1 ), during operation of circuit  200 , power supply circuit  202  operates as explained above regarding power supply  102  and PTT  206  operates as switch  106 . Accordingly, a user (not shown) activates switch  202  and speaks into microphone  208  first giving a password and then issuing a voice command. Amplifier  210  amplifies both the password and the voice command. CVSD unit  212  digitizes the password and voice command. CVSD unit  212  then encodes the digitized password and voice command. WTWR unit  218  transmits the encoded digitized password and command utilizing antenna  220 . In one embodiment, the password and command are encrypted by micro-controller  216  before being encoded. Micro-controller unit  216  controls CVSD unit  212  and WTWR unit  218 , and when switch  206  is closed, micro-controller unit  216  utilizes antenna  220  and WTWR unit  218  to receive wireless signals in the range of 910 to 920 Megahertz (MHZ) and then searches for an encoded signal. If a clock is derived from any signals received, then micro-controller unit  216  does not transmit any of the ID, the password, and the command. Accordingly, data collision between multiple controllers is avoided. 
     Power supply circuit  202  further includes an N-Channel mosfet  250  connected to a terminal (not shown) of battery  204 , and a pnp transistor  252  connected to battery  204  in parallel with mosfet  250 . Transistor  252  is also connected to a switch mode power supply  254  with boost mode topology. Power supply  254  is electrically connected to micro-controller  216 . 
     During operation of controller  100  including circuit  200 , power from battery  204  is not applied to any active circuitry of circuit  200  and is held off by a lack of gate voltage to mosfet  252 . When a user (not shown) closes PTT switch  206 , transistor  250  conducts voltage to switch mode power supply  254 . Since switch mode power supply  254  has boost mode topology, a primary supply voltage is stepped up to a higher voltage that is supplied to micro-controller  216 . Micro-controller  216  initializes and sets a power up pin high (not shown), supplying a gate voltage to mosfet  252 . An N-Channel (not shown) of mosfet  252  conducts electricity which reduces a loss of voltage through transistor  252  and provides control of power supply  254  to micro-controller  216 . The user may at this time open PTT switch  206  and circuit  200  retains power for a preset time period. Micro-controller  216  monitors PTT switch  206  for activity and allows transmission of audio signals to the base station only after receiving confirmation of a valid ID and password. In an alternative embodiment, micro-controller  216  monitors PTT switch  206  for activity and allows transmission of audio signals to the base station only after receiving confirmation of a valid ID. 
     FIG. 2A is an enlarged view of the switch mode power supply  254  (shown in FIG.  2 ). FIG. 2B is an enlarged view of one portion of the audio output  214  (shown in FIG.  2 ). FIG. 2C is an enlarged view of another portion of the audio output  214  (shown in FIG.  2 ). FIG. 2D is an enlarged view of the CVSD unit  212  (shown in FIG.  2 ). FIG. 2E is an enlarged view of the WTWR unit  218  (shown in FIG.  2 ). FIG. 2F is an enlarged view of the micro-controller  216  (shown in FIG.  2 ). 
     FIG. 3 is a block diagram of a base station  300  for one embodiment of a speech recognition system (not shown in FIG.  3 ). Base station  300  includes an antenna  302  electrically connected to an acoustical wave transmitter and wave resonator (WTWR)  304  which is electrically connected to a micro-controller  310 . Micro-controller is electrically connected to a serial bus interface  312  and a CVSD  306 . CVSD  306  is electrically connected to an amplifier  308  and a micro-controller  310  electrically connected to a serial bus interface  312 . Micro-controller  310  is further electrically connected to a speech recognition unit  314  that is connected to a memory unit  316  and an audio output  318 . Bus  312  is coupled (such as by one of mechanically, electrically, phonically, and optically) to a controlled device  320 . In an exemplary embodiment, controlled device includes a control module (not shown) and bus  312  is electrically coupled to the control module. Base station  300  further includes a power supply  322 . 
     During operation of base station  300 , WTWR  304  receives input from antenna  302 . Upon receipt of an active signal, WTWR  304  provides a signal received indication (not shown) to micro-controller  310 . Micro-controller  310  looks for a valid ID after micro-controller  310  receives the signal received indication. The digital ID is received and decoded by micro-controller  310  to confirm whether or not the ID is valid by comparing the decoded ID with at least one stored ID. In addition, micro-controller  310  receives a password which is converted from a digital to an analog signal by CVSD  306 . The analog signal is sent to speech recognition unit  314 , which compares the password analog signal to at least one password stored in memory  316 . If a valid password is found, an audible voice command is then received. Each time an audible signal is received, micro-controller  310  enables CVSD  306  to receive a new input (not shown) by cycling a clock input (not shown). After receiving an audible voice command, the command is converted to analog and compared to at least one audible profile of a pre-set voice command stored in memory  316 . If a valid command is received, a control signal is provided to micro-controller  310  and then from micro-controller  310  to serial bus  312  and from serial bus  312  to the controlled device  320 . If a valid password was just previously received before receiving the command control signal, a control signal command output is provided enabling subsequent commands to be received for a predetermined time. In an alternative embodiment, when a valid command is received, audio output  318  generates an audible confirmation. In an exemplary embodiment, the audible confirmation is phonemic such as, for example “alarm activated”. In an alternative embodiment, the audible confirmation is non-phonemic such as, for example, a beep. In a further alternative embodiment, controller  100  (shown in FIG. 1) generates the audible confirmation. 
     FIG. 4 is a schematic diagram of power supply  322  with 12 volt DC input from a transformer plugged into a standard household current outlet (not shown) or a 12 volt battery connection  402 . Power supply  322  includes an on/off switch  404 . When switch  404  is on, power supply  322  provides a 5 volt DC power feed  406  and a 3.3 volt power supply feed  408  for base station  300  (shown in FIG.  3 ). Power supply  322  includes bypass capacitors  410  and  412  and voltage hold-up capacitors  414  and  416 . Power supply  322  further includes two pull-up resistors  418  and  420 . 
     FIG. 5 is a schematic diagram of a voice recognition unit  500  that exemplifies one embodiment of speech recognition unit  314  (shown in FIG.  3 ). Unit  500  includes a speech recognition chip  502 , a memory storage unit  504  for voice prompt patterns, and a memory storage device  506  for passwords, at least one ID, and commands needed to control controlled device  320  (shown in FIG.  3 ). 
     FIG. 5A is an enlarged view of memory storage unit  504  (shown in FIG.  5 ), and FIG. 5B is an enlarged view of speech recognition chip  502  (shown in FIG.  5 ). 
     FIG. 7 is a schematic diagram of an audio amplifier  700  that, in one embodiment, is included in audio output  318  (shown in FIG.  3 ). Connector  600  and amplifier  700  are of substantially conventional design and, accordingly, are not described in detail. 
     FIG. 8 is a schematic diagram of a receive and transmit module amplifier  800  including WTWR  304  (shown in FIG.  3 ), antenna  302  (shown in FIG.  3 ), and CVSD  306  (shown in FIG.  3 ). Amplifier  800  is powered by 3.3 volt power supply feed  408  from power supply circuit  202  (shown in FIG.  4 ). FIG. 8A is an enlarged view of speech recognition unit  314  (shown in FIGS.  3  and  8 ). FIG. 8B is an enlarged view of WTWR  304  (shown in FIG.  8 ). FIG. 8C is an enlarged view of a portion of amplifier  800  (shown in FIG.  8 ). 
     FIG. 9 is a schematic diagram of a micro-controller  900  suitable for use as micro-controller  310  (shown in FIG.  3 ). FIG. 9A is an enlarged view of micro-controller  900  (shown in FIG.  9 ), and FIG. 9B is an enlarged view of a communication interface  902 . FIG. 10 is a block diagram of a secure remote voice activation system  1000  including controller  100  (shown in FIG. 1) and base station  300  (shown in FIG. 3) in wireless communication. As explained above, controller  100  transmits an ID, a password, and at least one voice command. Base station  300  receives the transmissions from controller  100 , and base station  300  controls controlled device  320  (shown in FIG.  3 ). In an exemplary embodiment, secure remote voice activation system  1000  is an automobile remote voice activation system. 
     While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.