Abstract: An apparatus for a beam steering device includes a rotator constituting a cylindrical body extending along an axis and defining a central passage therethrough. A wedge-shaped prism is secured to the body within the central passage. The prism has a first surface extending perpendicular to the axis and a second surface extending transverse to the axis. A drive member is provided on one of an axial end surface and a radially outer surface of the body for rotating the rotator. An encoder member is provided on the same surface of the body as the drive member for tracking the position of the rotator.

Abstract: A beam steering device includes a housing and a transceiver that emits and receives light beams through at least one opening in the housing. A rotator includes a cylindrical body rotatably mounted within the housing axially between the transceiver and the at least one opening. A wedge-shaped prism is secured within the body and includes a first surface extending perpendicular to the axis and a second surface extending transverse to the axis. An encoder member and a drive member are provided on an outer surface of the body. Sensors are mounted to the housing to sense the encoder member and provide an encoder signal indicative of a rotational position of the prism about the axis. At least one drive element is mounted to the housing and applies force to the drive member to rotate the body and prism about the axis for steering light beams propagating through the prism.

Abstract: An apparatus for a beam steering device includes a rotator constituting a cylindrical body extending along an axis and defining a central passage therethrough. A wedge-shaped prism is secured to the body within the central passage. The prism has a first surface extending perpendicular to the axis and a second surface extending transverse to the axis. A drive member is provided on one of an axial end surface and a radially outer surface of the body for rotating the rotator. An encoder member is provided on the same surface of the body as the drive member for tracking the position of the rotator.

Abstract: A beam steering device includes a housing and a transceiver that emits and receives light beams through at least one opening in the housing. A rotator includes a cylindrical body rotatably mounted within the housing axially between the transceiver and the at least one opening. A wedge-shaped prism is secured within the body and includes a first surface extending perpendicular to the axis and a second surface extending transverse to the axis. An encoder member and a drive member are provided on an outer surface of the body. Sensors are mounted to the housing to sense the encoder member and provide an encoder signal indicative of a rotational position of the prism about the axis. At least one drive element is mounted to the housing and applies force to the drive member to rotate the body and prism about the axis for steering light beams propagating through the prism.

Abstract: A volume level and crossfade controller with programmable fades and audio stream priority controls saturation for a multiple audio stream mixer. Start of fade and end of fade events trigger updates of relative volume level targets and volume ramps.

Abstract: A volume level and crossfade controller with programmable fades and audio stream priority controls saturation for a multiple audio stream mixer. Start of fade and end of fade events trigger updates of relative volume level targets and volume ramps.

Abstract: Beat matching for two audio streams extracts beats from each, computes a conversion ratio from one stream to the other stream by an initial beat alignment plus a stability-maintaining beat alignment. A variable resampling converter or time scale modifier adjusts one stream to align beats with those of the other (reference) stream. Thus for cross-fading two music streams the beats of the fading-in stream can be matched to those of the fading-out stream for a seamless transition.

Abstract: Beat matching for two audio streams extracts beats from each, computes a conversion ratio from one stream to the other stream by an initial beat alignment plus a stability-maintaining beat alignment. A variable resampling converter or time scale modifier adjusts one stream to align beats with those of the other (reference) stream. Thus for cross-fading two music streams the beats of the fading-in stream can be matched to those of the fading-out stream for a seamless transition.

Abstract: Beat matching for two audio streams extracts beats from each, computes a conversion ratio from one stream to the other stream by an initial beat alignment plus a stability-maintaining beat alignment. A variable resampling converter or time scale modifier adjusts one stream to align beats with those of the other (reference) stream. Thus for cross-fading two music streams the beats of the fading-in stream can be matched to those of the fading-out stream for a seamless transition.

Abstract: The keypad interface element of this invention uses a relaxation oscillator and a digital keypad processor having a counter/timer to decode specific keys. The RC portion of the relaxation oscillator includes a resistance ladder and a set of momentary on pushbutton switches disposed change resistance dependent upon which key is pressed. This causes the relaxation oscillator to produce an output signal having a corresponding frequency. The counter/timer of the digital keypad processor produces a count corresponding to the oscillator frequency. The digital keypad processor latches and holds a binary number specifically identifying the depressed key. A state machine in the digital keypad processor provides transient-free, noise immune keypad decoding.

Abstract: Beat matching for two audio streams extracts beats from each, computes a conversion ratio from one stream to the other stream by an initial beat alignment plus a stability-maintaining beat alignment. A variable resampling converter or time scale modifier adjusts one stream to align beats with those of the other (reference) stream. Thus for cross-fading two music streams the beats of the fading-in stream can be matched to those of the fading-out stream for a seamless transition.

Abstract: Asynchronous sampling rate converter with input/output frequency ratio estimation and polyphase filtering uses FIFO level feedback to adaptively control frequency ratio estimation.

Abstract: The keypad interface element of this invention uses a relaxation oscillator and a digital keypad processor having a counter/timer to decode specific keys. The RC portion of the relaxation oscillator includes a resistance ladder and a set of momentary on pushbutton switches disposed change resistance dependent upon which key is pressed. This causes the relaxation oscillator to produce an output signal having a corresponding frequency. The counter/timer of the digital keypad processor produces a count corresponding to the oscillator frequency. The digital keypad processor latches and holds a binary number specifically identifying the depressed key. A state machine in the digital keypad processor provides transient-free, noise immune keypad decoding.

Abstract: The keypad interface element of this invention uses a relaxation oscillator and a digital keypad processor having a counter/timer to decode specific keys. The RC portion of the relaxation oscillator includes a resistance ladder and a set of momentary on pushbutton switches disposed change resistance dependent upon which key is pressed. This causes the relaxation oscillator to produce an output signal having a corresponding frequency. The counter/timer of the digital keypad processor produces a count corresponding to the oscillator frequency. The digital keypad processor latches and holds a binary number specifically identifying the depressed key. A state machine in the digital keypad processor provides transient-free, noise immune keypad decoding.

Abstract: An audio player permits compressed or uncompressed audio CDs to be played. The preferred player includes a spindle motor control that causes the CD to be spun at a constant linear velocity that is commensurate with the encoding rate of the file being played. In this manner, the data can be continuously pulled of the CD at just the right rate so that, after being decoded and decompressed, the data can be played. The player also dynamically adjusts its constant linear velocity to the encoding rate of the file being played to permit files on the same disc having different encoding rates to be played.

Abstract: The keypad interface element of this invention uses a relaxation oscillator and a digital keypad processor having a counter/timer to decode specific keys. The RC portion of the relaxation oscillator includes a resistance ladder and a set of momentary on pushbutton switches disposed change resistance dependent upon which key is pressed. This causes the relaxation oscillator to produce an output signal having a corresponding frequency. The counter/timer of the digital keypad processor produces a count corresponding to the oscillator frequency. The digital keypad processor latches and holds a binary number specifically identifying the depressed key. A state machine in the digital keypad processor provides transient-free, noise immune keypad decoding.

Abstract: An audio player permits compressed or uncompressed audio CDs to be played. The preferred player includes a spindle motor control that causes the CD to be spun at a constant linear velocity that is commensurate with the encoding rate of the file being played. In this manner, the data can be continuously pulled of the CD at just the right rate so that, after being decoded and decompressed, the data can be played. The player also dynamically adjusts its constant linear velocity to the encoding rate of the file being played to permit files on the same disc having different encoding rates to be played.

Abstract: A method of AC induction motor speed control employing a rotor flux based MRAS (Model Reference Adaptive System) speed observer. Rotor flux-based MRAS speed observers develop two independent rotor flux estimates. The reference rotor flux estimate is based on the currents and voltages in the stator windings, and the adaptive estimate is based on the stator currents and the measured or estimated rotor speed. These two estimates are compared by taking the cross product between them, and this error signal is passed into a proportional-integral (PI) controller, which adjusts the speed until the flux estimates agree with one another. While this method is well-established, the estimator poles become lightly damped at high speeds and prone to stability problems. In this invention, the upper speed range of the rotor flux-based MRAS speed observer is extended by discretely or continuously modifying the gain/bandwidth parameters of the low-pass filter in the adaptive flux estimator as a function of estimated speed.

Abstract: A method of AC induction motor speed control employing a rotor flux based MRAS (Model Reference Adaptive System) speed observer. Rotor flux-based MRAS speed observers develop two independent rotor flux estimates. The reference rotor flux estimate is based on the currents and voltages in the stator windings, and the adaptive estimate is based on the stator currents and the measured or estimated rotor speed. These two estimates are compared by taking the cross product between them, and this error signal is passed into a proportional-integral (PI) controller, which adjusts the speed until the flux estimates agree with one another. While this method is well-established, the estimator poles become lightly damped at high speeds and prone to stability problems. In this invention, the upper speed range of the rotor flux-based MRAS speed observer is extended by discretely or continuously modifying the gain/bandwidth parameters of the low-pass filter in the adaptive flux estimator as a function of estimated speed.

Abstract: A print head motor control system uses a desired function of print head position versus time and a measured print head position to form an error signal. The print head controller forms a motor drive signal from the sum of a first term corresponding to the square root of the absolute value of the error signal and a second term corresponding to a dead band signal having a predetermined slope if said error signal exceeds a predetermined value. The desired function of print head position versus time may be formed by double integrating a desired function of print head acceleration versus time. The print head motor control preferably also includes a velocity loop subtracting a print head velocity estimated from the measured print head position from the sum. The print head motor control is preferably implemented using a microprocessor.