Patent Publication Number: US-8525562-B1

Title: Systems and methods for providing a clock signal using analog recursion

Description:
BACKGROUND 
     In the past, clock signals have been generated using a variety of techniques. One common technique is to use the mechanical resonance of a vibrating crystal of piezoelectric material to create a periodic electrical signal. While common, this technique has drawbacks, including the fact that, once created, such a mechanism cannot be further tuned. What is needed is a system that can generate a stable, tunable clock signal usable for a wide range of purposes. 
     SUMMARY 
     This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This summary is not intended to identify key features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
     In some embodiments, a system for generating a clock signal is provided. The system comprises a mixing device, a set of output devices, and a set of input devices. The mixing device includes a set of input channels, a mixing circuit configured to combine a set of input signals from the set of input channels into a mixed input signal, a set of output channels configured to generate output signals based on the input signals, and a clock output channel configured to output a signal usable as a clock signal. The set of output devices is coupled to the set of output channels and is configured to generate output based on the output signals. The set of input devices is coupled to the set of input channels and is configured to generate input signals based on the output generated by the set of output devices. 
     In some embodiments, a method of producing a clock signal is provided. A recursion device receives a set of input signals from a set of input sensor devices. A set of output signals is produced based on the set of input signals. The set of output signals are provided to a set of output devices to affect the set of input signals. A clock signal is generated by sampling a state of the recursion device. 
     In some embodiments, an analog recursion device is provided. The analog recursion device includes a mixing circuit and a set of recursion loops coupled to the mixing circuit. The analog recursion device is configured to receive a set of signals via the set of recursion loops, process the set of signals using the mixing circuit, provide the processed set of signals to the set of recursion loops, and provide a state to be sampled to generate a clock signal. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a schematic drawing illustrating an exemplary system configured according to various aspects of the present disclosure; 
         FIG. 2  is a schematic drawing illustrating an exemplary configuration of an analog recursion system according to various aspects of the present disclosure; 
         FIG. 3  is a block diagram that illustrates components included in an exemplary analog recursion system according to various aspects of the present disclosure; 
         FIG. 4  illustrates an exemplary embodiment of a method of producing a clock signal according to various aspects of the present disclosure; and 
         FIG. 5  illustrates aspects of an exemplary embodiment of an analog recursion system that embodies various aspects of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  is a schematic drawing illustrating an exemplary system  100  configured according to various aspects of the present disclosure. An analog recursion device  102  is coupled to and drives a clock display  104 . The analog recursion device  102  exhibits periodically recurring behavior that is remarkably stable and tunable, which may be converted into a clock signal. The clock signal is provided to a mechanism that moves hands on the clock display  104  to display the passage of time. One of ordinary skill in the art will recognize that periodic signals generated by the analog recursion device  102  may be used in a fashion similar to a periodic signal generated by a crystal oscillator to drive a stepping motor or the like to move the hands on the clock display  104 . One of ordinary skill in the art will recognize that such a periodic signal could be used for other purposes as well, including, but not limited to, clocking a computer processor, synchronizing a communication transmission, and/or the like. While embodiments are primarily discussed herein that harness the behaviors of analog recursion devices to generate clock signals, it will be readily apparent that behaviors of analog recursion devices could be used for purposes other than generating clock signals. 
       FIG. 2  is a schematic drawing illustrating an exemplary configuration of an analog recursion system  200  according to various aspects of the present disclosure. An analog recursion device  214  is configured to combine one or more analog recursion loops. As illustrated, the analog recursion device  214  is coupled to three recursion loops, but in other embodiments, more or fewer recursion loops may be present. In a first recursion loop, an output of the analog recursion device  214  is provided to an electromagnetic oscillator  204  and causes the electromagnetic oscillator  204  to resonate. Oscillations within the electromagnetic oscillator  204  are detected by an inductive coil  202  and are converted to an analog signal provided to an input of the analog recursion device  214 . In a second recursion loop, an output of the analog recursion device  214  is provided to a loudspeaker  208 . Sound produced by the loudspeaker  208  is detected by a microphone  206 , which converts the sound to an analog signal provided to an input of the analog recursion device  214 . In a third recursion loop, an output of the analog recursion device  214  is provided to a display device  212 . The display device  212  generates a display based on the signal received from the analog recursion device  214 . A camera  210  captures the display, and generates an analog signal based on the captured information. The analog signal from the camera  210  is provided to an input of the analog recursion device  214 . 
     The various input signals are processed by the analog recursion device  214 , which generates the corresponding output signals. The analog recursion device  214  unifies and harmonizes the input signals (in various distinct formats) and output signals (in various distinct formats) via their recursion through the analog recursion device  214 , thus producing a machine state within the analog recursion device  214 . The input and output signals, or other phenomena generated within the analog recursion device  214  according to the machine state, may be sampled to generate an output signal  216 . This output signal  216  exhibits properties that are usable as a clock signal. In some embodiments, an input signal or an output signal may be sampled to generate the output signal  216 . In some embodiments, the output signal  216  may be generated by sampling an indicator of machine state within the analog recursion device  214 , such as an LED that indicates that a predetermined threshold has been crossed and/or the like. In some embodiments, more than one input signal, output signal, or indicator of machine state may be sampled to produce the output signal  216 . 
     Some examples of suitable inductive coils  202 , electromagnetic oscillators  204 , microphones  206 , cameras  210 , and display devices  212  are discussed further below, but should be understood as exemplary only. In other embodiments, more, fewer, or different devices could be used within recursion loops connected to the analog recursion device  214 . 
     In some embodiments, more than one output may be provided to a given output device. For example, a display device  212  may receive an audio signal and a separate video signal from the analog recursion device  214 , even if it only the video signal is monitored by the camera  210 . In some embodiments, more than one input may be combined in a single loop. For example, an output from the microphone  206  and an output from the camera  210  may be combined before being provided as a single input to the analog recursion device  214 . In some embodiments, no input or output devices may be included in a recursion loop. That is, an output of the analog recursion device  214  may be coupled directly to an input of the analog recursion device  214  to establish a recursion loop. 
     In some embodiments, the first recursion loop, the second recursion loop, and the third recursion loop may be isolated from each other. In other words, the microphone  206  may be situated to only sense sound emitted by the loudspeaker  208 , the camera  210  may be situated to only monitor patterns presented by the display device  212 , and/or the like. In some embodiments, the recursion loops may be configured to influence each other. For example, the microphone  206  may be situated to sense sound emitted by the loudspeaker  208  as well as by the display device  212 , the electromagnetic oscillator  204 , and/or the like. The recursion loops may also be isolated from each other or may influence each other within the analog recursion device  214 . 
     In some embodiments, at least one output device and at least one corresponding input sensor device may be incorporated within the analog recursion device  214 . Various components of the analog recursion system  200  may be miniaturized and, though functionally similar to the separate devices illustrated in  FIG. 2 , the analog recursion system  200  may be embodied in a single device. In such an embodiment, custom miniaturized components that output or sense similar oscillating phenomena to those illustrated and discussed above may be used within the single device to establish the recursion loops. 
     The output signal  216  may take various forms. In some embodiments, the output signal  216  may be generated by monitoring a peak amplitude of a sum of signals propagating through one or more of the recursion loops. A clock pulse may be generated for the output signal  216  upon detecting that the peak amplitude has crossed a threshold. In such an embodiment, the output signal  216  may be a square wave clock signal, wherein a high state of the output signal  216  indicates that the peak amplitude is above the threshold. Upon tuning the recursion loops to a predetermined frequency, such a clock signal will represent a stable, periodic signal. In some embodiments, the output signal  216  may be a sine wave signal, which may either be used directly as a clock signal, or may be converted to a square wave clock signal by an external device. 
     The use of an analog recursion system as described herein for generating stable periodic signals has numerous advantages compared to other solutions. In the disclosed analog recursion system, the stable harmonic pathways are directly analogous to geostationary orbits in orbital mechanics, and therefore serve as a reference. Accordingly, one benefit is that no external reference is necessary, as the recursion loops, in a convergent search for thermodynamic efficiency, provide a self-referential oscillator mechanism. While different components and configurations may exhibit superficially different oscillatory phenomena, it is also true that the analog recursion mechanisms described herein are perhaps a unique means by which the fundamentally and universally organic harmonic pathways can be isolated and identified. In other words, a clock constructed on the principle of analog recursion as disclosed herein not only does not require an external reference, but may also be the means for constructing a clock capable of serving as such a reference for all other clocks. 
       FIG. 3  is a block diagram that illustrates components included in an exemplary analog recursion system  300  according to various aspects of the present disclosure. The analog recursion device  301  is similar to the analog recursion device  214  and the analog recursion device  102  illustrated and described above. The analog recursion device  301  includes a set of analog input channels  314 ,  316 ,  318 . The set of analog input channels  314 ,  316 ,  318  are configured to receive input from a corresponding set of input sensors  302 ,  304 ,  306  via a corresponding set of input coupling devices  308 ,  310 ,  312 . Though three analog input channels  314 ,  316 ,  318 , input sensors  302 ,  304 , and  306 , and input coupling devices  308 ,  310 ,  312  are present in the illustrated embodiment, in other embodiments, more or fewer of any of these components may be present. 
     In some embodiments, the sensor devices are configured to sense a condition and to generate a signal based on the sensed condition. A wide variety of devices may be used as sensor devices. For example, a simple induction coil may be used as a sensor device. As a more complex example, a CCD image sensor may be used as a sensor device. In some embodiments, at least one of the sensor devices may be a complex device that includes a sensor as a subcomponent, such as a video camera and/or the like. 
     In some embodiments, the coupling devices are configured to provide the signal generated by the sensor devices to the analog recursion device  301 . In some embodiments, a coupling device may simply provide a transmission path for the signal from a sensor device to the analog recursion device  301 . As one nonlimiting example, a microphone cable may act as a coupling device that couples a microphone to the analog recursion device  301 . As another nonlimiting example, a ¼ inch patch cable may act as a coupling device that couples an output of a guitar having an inductive coil sensor device to the analog recursion device  301 . In some embodiments, a coupling device may perform further processing of the signal generated by a sensor device before providing a processed signal to the analog recursion device  301 . For example, the guitar discussed above may be coupled to an effects unit. While acting as a coupling device, the effects unit may process the signal generated by the guitar before providing a processed signal to the analog recursion device  301 . In some embodiments, multiple coupling devices may be used to couple a single sensor device to the analog recursion device  301 . For example, a patch cable may be used to couple an output of a guitar to one or more chained effects units, and an additional patch cable may be used to couple an output of the effects units to the analog recursion device  301 . 
     The signals received by the set of analog input channels  314 ,  316 ,  318  are provided to a mixing circuit  320 . The mixing circuit  320  combines the signals from the set of analog input channels  314 ,  316 ,  318  based on settings of a set of mixer controls  322  to create a mixed input signal. The set of mixer controls  322  may affect the mixed input signal in various ways. For example, the set of mixer controls  322  may include level controls corresponding to each of the analog input channels  314 ,  316 ,  318  that change a contribution of the analog input channels  314 ,  316 ,  318  to the mixed input signal. As another example, the set of mixer controls  322  may include equalizer controls corresponding to each of the analog input channels  314 ,  316 ,  318  that change a balance of various frequency components provided to the mixed input signal for each analog input channel  314 ,  316 ,  318 . In some embodiments, additional mixer controls  322  for each channel, such as pan controls, filter controls, and/or the like may be provided for each analog input channel  314 ,  316 ,  318 , and in some embodiments, mixer controls  322  may be provided that affect each of the analog input channels  314 ,  316 ,  318  equally or affect the mixed input signal after the individual components from the analog input channels  314 ,  316 ,  318  have been combined. 
     Once combined, the mixing circuit  320  provides the mixed input signal to a splitter circuit  330 . The splitter circuit  330  is configured to provide the mixed input signal to a set of analog output channels  332 ,  334 ,  336  as a mixed output signal. Similar to the set of analog input channels  314 ,  316 ,  318 , the set of analog output channels  332 ,  334 ,  336  are configured to provide the mixed output signal to a corresponding set of output devices  344 ,  346 ,  348  via a corresponding set of output coupling devices  338 ,  340 ,  342 . The set of output devices  344 ,  346 ,  348  and the set of input sensors  302 ,  304 ,  306  are configured such that the set of input sensors  302 ,  304 ,  306  sense the output of the set of output devices  344 ,  346 ,  348  in order to close a set of analog recursion loops. 
     In some embodiments, the mixing circuit  320  may generate more than one mixed output signal. As one nonlimiting example, the mixing circuit  320  may generate a monaural signal that combines multiple input signals into a single signal, as well as stereo signals that split at least some input signals into a left channel signal and a right channel signal. As another nonlimiting example, the mixing circuit  320  may generate separate signals in distinct frequency bands. As yet another nonlimiting example, the mixing circuit  320  may generate multiple mixed output signals based on different input signals. For instance, a first mixed output signal may be based only on a signal received from analog input channel one  314  and a signal received from analog input channel two  316 , while a second mixed output signal may be based on signals received from all of the analog input channels  314 ,  316 ,  318 . 
     In the illustrated embodiment, the splitter circuit  330  also provides a signal to a clock output channel  326 . The clock output channel  326  is configured to provide the mixed output signal to a clock output coupling device  328 . In some embodiments, the clock output coupling device  328  may rectify or clip the mixed output signal to generate a digital signal usable as a clock signal, as discussed above. In some embodiments, the clock output coupling device  328  may provide the analog mixed output signal to be used as a clock signal based on its frequency. Though the illustrated embodiment is configured such that the splitter circuit  330  provides a signal to the clock output channel  326 , in other embodiments, the clock output channel  326  may receive a signal from a different portion of the analog recursion system  300 . For example, in some embodiments, the clock output channel  326  may receive a signal based on a signal received by one or more of the analog input channels  314 ,  316 ,  318  before being combined with other signals by the mixing circuit  320 . In some embodiments, the clock output coupling device  328  may combine multiple signals sampled from the analog recursion device  301  to generate clock output. 
     In some embodiments, the analog recursion device  301  may also include one or more amplifier circuits. The amplifier circuits may be coupled to an input or an output of any of the channels discussed above, and may either amplify an input signal to have a more significant effect within the analog recursion device  301 , or may amplify an output signal to be more intensely reproduced by an output device. 
       FIG. 4  illustrates an exemplary embodiment of a method  400  of producing a clock signal according to various aspects of the present disclosure. From a start block, the method  400  proceeds to block  402 , where a set of input sensor devices generate a set of input sensor signals. At block  404 , the set of input sensor signals are provided to a set of analog input channels of an analog recursion device via a set of input coupling devices. As discussed above, the input coupling devices may simply convey the input sensor signals to the analog input channels, or may perform processing on the input sensor signals before providing a processed signal to the analog input channels. 
     The method  400  proceeds to block  406 , where a mixing circuit of the analog recursion device combines the analog input channels based on a set of mixer settings to produce a mixed input signal. In some embodiments, the set of mixer settings may be tuned in order to change one or more characteristics of a signal eventually provided to a clock output channel, such as its amplitude, frequency, and/or the like. At block  410 , a splitter circuit provides a set of output signals to a set of analog output channels based on the amplified mixed input signal and a set of splitter settings. As discussed above, the set of output signals may include output signals based on different constituent signals, such as a monaural output signal, a left stereo output signal, a right stereo output signal, an output signal containing added effects, and/or the like. Next, at block  412 , the set of analog output channels provide the set of analog output signals to a set of output devices via a set of output coupling devices. At block  414 , the set of output devices produce output to be sensed by the set of input sensor devices. As discussed above, the output devices may be closely coupled to corresponding input sensor devices such that each recursion loop is isolated from the others, or at least one of the input sensor devices may be configured to sense output or other characteristics of more than one output device. In some embodiments, at least one recursion loop may not use an output device or an input sensor device, but may instead include an analog output channel coupled directly to an analog input channel. 
     At block  416 , a signal is provided to a clock output channel for use as a clock signal. The signal provided to the clock output channel is based on at least one of the other signals propagating through the system, and may be based on or otherwise similar to one of the set of output signals or signals received by the analog input channels. As discussed above, in some embodiments, a device may be coupled to the clock output channel in order to convert the signal to a clock signal, while in other embodiments, an analog signal output by the clock output channel may itself be used as a clock signal. Though block  416  is illustrated after block  414 , in some embodiments, the actions associated with block  416  may be performed at one or more times at any point during the method  400 , continuously during the execution of the method  400 , and/or at any other appropriate time. 
     As illustrated, the method  400  then returns to block  402  and repeats an arbitrary number of times. One of ordinary skill in the art will recognize that the method  400  may repeat for only a predetermined number of times, or may be terminated at any point. 
     While general concepts, techniques, and configurations used by embodiments of an analog recursion device are discussed and illustrated above, a description of an exemplary embodiment of an analog recursion device constructed from existing components may be instructive.  FIG. 5  illustrates aspects of an exemplary embodiment of an analog recursion system that embodies various aspects of the present disclosure. One of ordinary skill in the art will understand that none of the particular components described are necessary, and be replaced with existing components of similar functionality, or may be replaced with custom-built or miniaturized components that provide similar functionality. 
     In  FIG. 5 , an analog audio mixer  502  serves as the analog recursion device discussed above. One example of a suitable analog audio mixer  502  is a Behringer® XENY 1202FX mixer, produced by Music Group IP Ltd., the operating manual for which is available from Music Group IP Ltd. and is incorporated by reference herein in its entirety. One of ordinary skill in the art will understand that other analog audio mixers with similar functionality and capabilities may be used instead. As illustrated, channels one through four of the analog audio mixer  502  are channels that may act as monaural channels or stereo channels depending on a type of signal supplied to the channel, while channels five and six are stereo channels. The other illustrated inputs and outputs will be familiar to one of ordinary skill in the art, and are described further in the operating manual incorporated by reference herein. One of ordinary skill in the art will recognize that the analog audio mixer  502  may have more or fewer inputs or outputs than those illustrated, and that certain inputs and outputs have been illustrated for clarity but are not numbered or described because they are not used by the illustrated embodiment. 
     Input is received by the analog audio mixer  502  from four external sources: a guitar output  504 , a microphone output  506 , a video camera output  508 , and an audio output  538  of a television. An inductive coil in a pickup of the guitar serves as an input sensor device, while the remainder of the guitar electronics and patch cable serve as an input coupling device. One example of a suitable guitar for producing the guitar output  504  is an SG® guitar from Gibson Guitar Corp. Such a guitar includes a pair of humbucker pickups, which are configured to eliminate interference or hum. Other similar guitars or pickups may be used instead. The guitar may be situated such that the pickup reacts to oscillations observable in one or more components of a power supply of the analog audio mixer  502  (not illustrated). While an audio output of the analog audio mixer  502  is not coupled to the power supply, the oscillations of the power supply will nevertheless be affected by signals propagating recursively through the analog audio mixer  502 . The microphone output  506  is provided by a Beta 58A® vocal microphone from Shure Incorporated. One of ordinary skill in the art will recognize that any similar microphone that may instead be used. A sensor of a video camera serves as another input sensor device. Any video camera having an analog composite video output (or individual component video outputs) that can be connected to an audio input of the analog audio mixer  502  may be used. One suitable camera is the Model Number IB5632MV, from Eyemax, though other similar cameras having composite video output may be used instead. 
     A television  532  may be used as both an output device and an input sensor device. In such a case, a suitable television  532  includes an analog audio input  534 , an analog video input  536  (such as a composite video input and/or the like), and an analog audio output  538 . One suitable television  532  is Model Number 24SL410U from Toshiba America, Inc., though other model televisions that include an analog audio input, an analog video input, and an analog audio output may also be suitable. 
       FIG. 5  illustrates how the described components may be connected to form an analog recursion system  500 . The guitar output  504  is connected to channel one line in  510  of the analog audio mixer  502 . The microphone output  506  is connected to the channel three line in  514  of the analog audio mixer  502 . The video camera output  508  is connected to the channel five/six left input  518  and the tape in right input  531  of the analog audio mixer  502 . The television audio output  538  is connected to the tape in left input  530  of the analog audio mixer  502 . 
     The main out right output  522  and the control out left output  524  of the analog audio mixer  502  are combined by a Y-shaped cable, and are connected to the channel two line in  512  of the analog audio mixer  502 . The FX send output  520  of the analog audio mixer  502  is connected to the channel four line in  516  of the analog audio mixer  502 . The tape out left output  526  is connected to the television audio in  534  of the television  532 , and the tape out right output  528  is connected to the television video in  536  of the television  532 . 
     One of ordinary skill in the art will recognize that each of these connections may be made by traditional analog connection cables such as ¼ inch patch cables, RCA cables, microphone cables, and/or the like. 
     The analog audio mixer  502  may also include a CD/TAPE TO MIX switch, a CD/TAPE TO CTRL switch, and/or an FX TO CTRL switch (not illustrated). As known to one of ordinary skill in the art, these switches determine which of the channels are included in the illustrated tape out left output  526 , the tape out right output  528 , and the ctrl out left output  524  (as well as other outputs that are not discussed further). In one embodiment, the CD/TAPE TO MIX switch may be engaged, but in other embodiments, other combinations of switches may be engaged. In one embodiment, an on-board digital effects processor of the analog audio mixer  502  is set to a bypass effect or otherwise disabled. However, in other embodiments, the on-board digital effects processor may be used to help tune the analog recursion system  500 . 
     Once the connections described above are made, the mixer settings may be used to determine input signals included in given output signals and to tune the analog recursion system  500  to a desired clock frequency. To help the analog recursion system  500  stabilize to a predetermined frequency, one or more tuning devices may be used. As an example, two BOSS TU-2 chromatic tuners may be coupled to the analog recursion system  500 . The first tuner may be coupled in-line with the guitar output  504  and the channel one line in  510 . The second tuner may be coupled in-line with the FX send output  520  and the channel four line in  516 . The settings of the analog audio mixer  502  may be adjusted until each of the tuners stabilizes on a particular note of the chromatic scale, such as G# or any other tone in the chromatic scale with infinite semitone possibilities. 
     Stable periodic phenomena occur within the analog recursion system  500  that may be harnessed for a variety of purposes. For example, the stable periodic phenomena may be sampled to produce a clock signal. In the illustrated analog audio mixer  502 , clip LEDs  540 ,  542 ,  544 ,  546  are provided for one or more channels. Periodic flashing of the clip LEDs  540 ,  542 ,  544 ,  546  may be sampled by a photodetector, or by a probe wired directly into the LED circuit, to produce a clock signal. 
     While analog signals are primarily discussed above for the sake of discussion and implementation, one of ordinary skill in the art will recognize that digital or other signals may be used without departing from the spirit and scope of the disclosure. For example, a digital recursion system constructed and operating similar to the analog recursion system discussed herein could also be used. Even in the discussed analog recursion system, a signal traditionally described as digital may be treated as an analog input or output signal and used as discussed herein. Further, an output signal traditionally considered an audio signal may be provided to an output device traditionally considered to accept video input of a predetermined format, even if the audio signal is not in the predetermined format. 
     While illustrative embodiments have been illustrated and described, it will be appreciated that various changes can be made therein without departing from the spirit and scope of the disclosure.