Abstract: This invention recovers the time waveform envelope of a human voice signal ithout the loss of subtleties providing speaker recognition cues and voice quality.This is accomplished by rectifying the voice envelope and then obtaining slope information about the original time waveform to detect peaks which are successively held by sample and hold circuitry.

Abstract: In a speech processing arrangement for synthesizing more natural sounding speech, a speech signal is partitioned into intervals. For each interval, a set of coded prediction parameter signals, pitch period and voicing signals, and a set of signals corresponding to the spectrum of the prediction error signal are produced. A replica of the speech signal is generated responsive to the coded pitch period and voicing signals as modified by the coded prediction parameter signals. The pitch period and voicing signals are shaped responsive to the prediction error spectral signals to compensate for errors in the predictive parameter signals whereby the speech replica is natural sounding.

Abstract: Apparatus, and a related method, for use with a speech analysis system, which derives coefficient parameters by linear prediction and utilizes an intermediate correlation technique that produces a set of auto-correlation coefficients. The apparatus includes an estimate register, circuitry for comparing the contents of the estimate register with a first auto-correlation coefficient and setting the estimate register to the value of the first coefficient if the first coefficient is less than or equal to the estimate register contents, and circuitry for incrementing the contents of the estimate register if the first coefficient is greater than the estimate register contents.

Abstract: A voice signal is transmitted digitally at reduced bit rate by use of data compression. The original frequency components of a telephone band width of the voice signal sampled at 8 KHz and quantized with 12 bits are transformed into three parameters: SIGNAL data representing adaptive quantization for lower frequency (300-800 Hz) sub-bands; COEF data representing pre-emphasized parcor type coefficients for the higher frequency (800-3000 Hz) band; and, ENERGY data representing higher frequency short term energy level. The three parameters are multiplexed for transmission in binary-code form, thereby representing a recoding of the original binary-coded voice signals.

Abstract: A completely self-contained, battery operated, portable voice system for the verbally handicapped which is sufficiently compact to be hand held. The system contains a preestablished vocabulary of words, phonemes, and phrases which are accessible by the non-verbal via a keyboard. The desired message is then phonetically spoken by a speech synthesizer contained in the unit upon the depression of a TALK key. For verbally handicapped persons with minimal motor capabilities, the present invention is adapted to be operable in a scrolling scanning or "scrolling" mode wherein the numerical display is automatically rotated in sequence and the selections entered by activating a sensor switch with a single body function to stop the display at the desired number.

Abstract: A reverberation sound producing apparatus includes a nonuniformly tapped delay line, a summing circuit applying an audio signal to the input of the tapped delay line and a feedback path coupling the output taps of the delay line back to its input through the summing circuit. A separate output path couples the reverberation signal from the feedback path to an output amplifier and speaker system. The feedback path is adjusted for minimizing loop gain and the effect of ripple in the frequency response of the delay line while the output path is adjusted for providing a smoothly decaying reverberation signal.

Abstract: A method and apparatus for analyzing and synthesizing speech information in which a predetermined vocabulary is spoken into a microphone, the resulting electrical signals are differentiated with respect to time, digitized, and the digitized waveform is appropriately expanded or contracted by linear interpolation so that the pitch periods of all such waveforms have a uniform number of digitizations and the amplitudes are normalized with respect to a reference signal. These "standardized" speech information digital signals are then compressed in the computer by subjectively removing and discarding redundant speech information such as redundant pitch periods, portions of pitch periods, redundant phonemes and portions of phonemes, redundant amplitude information (delta modulation) and phase informaton (Fourier transformation). The compression techniques are selectively applied to certain of the speech information signals by listening to the reproduced, compressed information.

Abstract: A synthetic-speech calculator includes a keyboard consisting of digit keys and function keys and, if desired, or more mode selectors, a desired number of registers for storing numerical information entered by the depression of selected ones of the digit keys, a read-only-memory for storing a large number of digital codes as sound quantizing information, counter means for specifying the address of the memory so as to take a specific digital code out of the memory, a digital-to-analogue converter for converting the specific digital code taken out of the memory into an audible sound signal, and a loud speaker driven by the audible sound signal and producing an audible sound. There are further provided means for producing audible sounds indicative of not only numerical information but also its associated conditional information having a particular meaning with respect to that numerical information, for example, position information, index information, tabulation information, etc.

Abstract: An analog sound signal the time axis of which is compressed is sampled responsive to a write clock signal and the sampled output is stored in an analog shift register having a given capacity, whereupon the stored signal is read out from the analog shift register responsive to a read clock signal the frequency of which is smaller than that of the write clock signal. The above described operation is alternately repeated, whereby the output signal read out from the analog shift register is compiled for sound synthesization. The synthesizing junction of the sound signal is controlled by a microcomputer. The microcomputer is adapted to evaluate the similarity of the data concerning the waveform at the trailing end portion of a preceding sound element stored in the random-access memory and the data concerning the waveform at the leading end portion of the succeeding sound element stored in the random-access memory.

Abstract: A system for utilizing audio frequency wiring circuits at drive-in theaters to transmit radio frequency signals to patron automobile radio receivers with increased efficiency and a reduction in radiation of the radio frequency signals. The system employs impedance matching networks, coupling networks and termination networks to enable the audio frequency wiring circuits to operate as transmission lines.

Abstract: An electric generator with winding and rotor design so that it powers and multiplexes several sensor inputs during rotor rotation. The rotor may be rotated by any means such as fluid (gas or liquid) or electric motors.

Abstract: This invention is an improvement of the intraplant communication system in U.S. Pat. No. 3,527,890. It comprises one base unit composed of a handset amplifier and speaker amplifier, each with its own integral power supply and each located on a common printed circuit board. This unit also features a disconnect device, formerly called a hook switch, which includes a radio frequency proximity detector which has no moving parts.

Abstract: This digital telephone conference system provides improved cancellation of reflective signals which cause echo-singing problems, such as caused by hydrid mismatches, for any number of telephone sets. Each telephone set is sequentially sampled for time sharing, and alternate samples are given opposite polarity signs before being summed, thereby making approximately half of the signals of opposite phase, for any number of telephone sets, for effective cancellation. Also, each member of the conference receives a sum signal of all telephone sets except his own.

Abstract: A device for aiding persons having a speech handicap, comprising a first transducer capable of picking up and transforming into an electrical signal the vibrations emitted by an element such as one of the vocal chords of the phonation mechanism of the person. In a first embodiment of the invention, the signal is treated by an electronic circuit comprising an amplifier which feeds a second transducer acting on another element such as the other vocal chord of the phonation mechanism so as to facilitate or reinforce the formation of sounds produced by said mechanism; in a second embodiment of the invention, the amplifier is followed by a rectifier feeding the second transducer which produces a mechanical action, like tension, in another element such as a muscle of the phonation mechanism in order to help close the glottis of the handicapped person.

Abstract: This data compression system further reduces previously-formed digital words representing samples of non-uniformly quantized and encoded analog speech, by normalizing and reencoding the original input digital word samples into smaller words using block coding wherein the input words are bit-reduced by normalizing a block of samples to the maximum amplitude sample value. Features of the invention include concatenating the most significant bit of the maximum value block code (first digital word) with the least significant bit of the segment bits part of the normalized input digital word (third digital word).

Abstract: Delay devices including CCD delay lines clocked and sampled to simulate a multitap delay line with a weighter, correlator and integrater connected to the delay line by switches which are operated to time share the weighter and correlator with each output of the delay line.

Abstract: A voice detector circuit including a slew-rate limited amplifier at the input thereof so as to reduce the interference with the voice detection process caused by impulse noise. The slew-rate limited amplifier is essentially transparent to audio signals, while providing severe attenuation of impulse noise components. The actual determination of the voice content of the audio signal is provided by comparing the average syllabic-rate content of the impulse noise limited, audio signal with the peak noise content thereof. Additionally, a logarithmic amplifier is included for the purpose of optimizing the separation of the syllabic-rate envelope from the audio signal.

Abstract: To produce a signal simulating the characteristics of the average human voice, a basic periodic waveform with generally sinusoidal sections separated by level sections is passed through a first filter for substantially equalizing its frequency components and is then shaped in a second filter whose transfer function approximates that of the vocal tract in a frequency band of 0 to 4 kHz. The basic waveform fed to the first filter may be modulated in amplitude and/or recurrence period by a pseudorandom signal from an ancillary generator.

Abstract: A telephone set for optical fibers lines having a coupler for directing a first part of the light received from the input optical fiber on a photo-cell and a second part of this light on a microphone modulating this second part without electrical intermediate apparatus, the photo-cell feed alternately a bell or a receiver, and the light modulated by the microphone is directed via a dialling system on the output optical fiber.

Abstract: Control panel arrangement for an audio equalizer features grouped horizontal and vertical slider controls for convenience in adjusting channel gain, bandwidth and frequency response.