Sharp Kabushiki Kaisha Corporation

Sharp Kabushiki Kaishi

Shuichi Yoshikawa

Yasumoto Murata

Yuji Nishiwaki

Takahiko Nakano

Michio Ikeuchi

Masahiko Watanabe

Shuichi Kawama

Atsunori Kitoh

Tomokazu Morio

In a signal reproducing device for reproducing voice signals from vector-quantized coded data, transferred or recorded coded data is extracted one by one, and the coded data extracted are given as initial values to a recurrence equation to generate a pattern composed of a predetermined number of data for every initial value. The thus generated patterns are sequentially output as reproduction data.

Signal reproducing device for reproducting voice signals with storage of

A DTMF signal judging apparatus includes a first power calculator, and second power calculator and a judging apparatus. The first power calculator calculates the overall power of an input signal or the power of the input signal outside the DTMF frequency band. The second power calculator calculates the power in the DTMF frequency band; or more specifically, calculates the power in both the higher and lower frequency band portions of the DTMF frequency band. The judging apparatus then compares the output from the first and second calculators, and determines whether the input signal is a DTMF signal based on the comparison.

DTMF signal judging apparatus

A voice reproducing device includes a data generator for sequentially providing digital data as an initial value to a recurrence equation and for generating a prescribed number of data with each given an initial value, a decoder for controlling the polarity of its output and the output time thereof in accordance with the data generated by the data generator and for outputting a pulse accordingly, and an analog integrating circuit for integrating the pulse output from the decoder.

Voice reproducing device

A DTMF signal receiving apparatus includes a DTMF signal receiver; and a DTMF signal judging circuit. The DTMF signal receiver includes an input section for receiving an input signal from an external apparatus; a plurality of first band-pass filters connected to the input section; a plurality of second band-pass filters connected to the input section; and an output section connected to the plurality of the first band-pass filters and the plurality of the second band-pass filters, for outputting a code based on a plurality of outputs from the plurality of the first band-pass filters and the plurality of the second band-pass filters. The DTMF signal judging circuit includes a first judging device connected to the plurality of the first band-pass filters, for outputting a first judgment signal based on a plurality of first outputs from the plurality of the first band-pass filters; a second judging device connected to the plurality of the second band-pass filters, for outputting a second judgment signal based on a plurality of second outputs from the plurality of the second band-pass filters; and a third judging device for judging whether the input signal is a DTMF signal or not based on the first judgment signal and the second judgment signal and for permitting the output section to output the code when judging that the input signal is a DTMF signal.

DTMF signal receiving apparatus equipped with a DTMF signal judging

A sound gain control device for automatically controlling a gain by which an output signal from a sound CODEC is multiplied is provided. Sound signals from a sound input device are processed by a non-linear conversion circuit so that the sound signals with small amplitudes are enlarged by extending the amplitudes and the time axis thereof, thereby to average the incidence probabilities of amplitudes. Then, a proper amplitude for a gain control is calculated based on the averaged signals by an amplitude calculating circuit, and a gain corresponding to the calculated amplitude is determined by a gain determining circuit and sent as a amplitude coefficient to a multiplier to which the sound signals from the sound input device are input through a sound CODEC.

Automatic sound gain control device and a sound recording/reproducing

In a signal encoding device, a voice signal is divided into subsignals each comprising a predetermined number of successive samples, and data trains are generated by giving initial values to a recurrence equation. The generated data trains are divided into patterns each comprising the same number of samples as the predetermined number. The distance between each pattern produced by the pattern dividing unit and each of the subsignals are calculated. The pattern that provides the smallest distance with respect to each of the subsignals is identified, and the initial value set in the recurrence equation for generation of the data train that constitutes the pattern is output as coded data representing the respective subsignal.

Signal encoding device

A modem including an identification signal detection section for detecting a specific identification signal during data transmission, a mode switching section for switching the mode from data transmit mode to control command accept mode when the identification signal is detected singly, and an identification signal deleting section for deleting one identification signal from the transmit data when successive identification signals are detected. During data transmission, the mode can be switched over to the control command accept mode by sending a specific identification signal from the data terminal equipment.

Multi-mode modem for automatically switching between data transmit and

An IC card with a built-in voice synthesizing function is provided which includes a solid-state memory containing vector-quantized coded data, a pattern generating means for generating patterns each composed of a prescribed number of digital data by repeatedly performing calculations using a recurrence equation with initial values given by coded data read out of the solid-state memory, a converter circuit for limiting the band of each pattern generated by the pattern generating means and converting into an analog voice signal, and a gain control circuit for adjusting the gain of the analog voice signal output from the converter circuit on the basis of gain data read out of the solid-state memory.

IC card with built-in voice synthesizing function

A voice signal is modulated using two carriers which are perpendicular to each other. The modulated signal is supplied to a low-pass filter, and then sampled. The sampled data are encoded, and then stored. When the stored data are to be reproduced, the data are decoded, and sampled. The sampled data are supplied to a demodulator through a low-pass filter.

Voice recording and reproducing apparatus having perpendicular carrier

A noise generating device comprises a generator (1) including a shift register (1a) which performs shift operations to sequentially shift a bit in an input stage to a next higher significant stage. An exclusive-OR circuit (1b) performs exclusive-OR operations between a pair of bits from selected stages of the shift register and feeds back to the input stage of the shift register. A filter (2) receives the pseudo-random data and outputs an analog signal. The filter comprises an operational amplifier (2a). Respective outputs of the stages of the shift register are alternately applied to non-inverting and inverting inputs of the operational amplifier through respective resistors (R1, . . . ,R23).

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Nara, Japan

Shuichi Yoshikawa