Matsushita Graphic Communication Systems, Inc.

Matsushita Electric Industrial Co., Ltd.

Panasonic Communications Co., Ltd.

Genzo Takagi

Yoshihiro Noguchi

Mitsuhiro Araki

Eizo Katayama

Nobuhiko Noma

Mikio Mizutani

Yoshihiko Noguchi

Motoyasu Ohno

Takashi Okiyama

Yoshinori Takahashi

According to the data amount stored in a jitter buffer, which temporarily stores obtained data from a received voice packet, an operation timing of an output process of the jitter buffer and a data process of a codec and a modem is adjusted, the codec and the modem processing data that is sequentially output from the jitter buffer.

Data communication apparatus and data communication method

A MODEM can shorten the processing time of an interface disposed between a data terminal equipment (DTE) and the MODEM. The MODEM stores an object program of a procedure in a memory and switches an operational mode of the MODEM automatically corresponding to the prescribed procedure thereby executing the procedure corresponding to the current operational mode. The MODEM further comprises a timer which monitors the transits time between a completed procedure and the next procedure, and the MODEM starts the process of a specified operational mode based on a mode-setting-instruction of the procedure as well as monitoring the transitions time by using the timer, and executing a next specified operational mode when the timer times out, thereby allowing the MODEM to perform the various operational mode switches.

Modulator and demodulator (MODEM)

The data transmission apparatus comprises a memory to store control information of a modem at each destination address, and a communication control section for issuing a short procedure shift notification signal to execute the short communication procedure when the control information is stored at the memory, and issuing an ordinary communication initiation signal to execute the ordinary communication procedure when the control information is not stored at the memory.

Data transmission apparatus and data reception apparatus

Modem apparatus and data communication method

A digital signal detection circuit includes a threshold value calculator calculating a threshold value from assumptive sampled values corresponding to various data patterns of a regenerated signal. The regenerated signal is obtained by regenerating data recorded on a recording medium by a regenerating head. The detection circuit also includes a Viterbi decoder carrying out Viterbi decoding of the regenerated signal with the threshold value determined by the threshold value calculator as a constant. The threshold value calculator variably controls the threshold value using a decoded output of the Viterbi decoder and a regenerated signal corresponding to the decoded output of the Viterbi decoder.

Digital signal detection circuit

A method of counting the number of tracks on an optical disk each track comprising a plurality of sectors each having an address segment and a plurality of data segments, each of the segments having at its head portion a region for recording an access code representing a track number to which the segment belongs. The method comprises the steps of sampling the access code number through an optical head, obtaining a code number difference (V0) between the present sampled access code number (GC) and the previous sampled access code number (GC1), and adding the code number difference to a track count value (TCNT) to obtain the number of the tracks that the optical head moves to traverse. This method can accurately and surely count the number of the tracks of an optical disk.

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Saitama, Japan

Genzo Takagi