Kokusai Denshin Denwa Kabushiki Kaisha

Kokusai Denshin Denwa Co., Ltd.

Yukio Nakagome

Hiroichi Teramura

Yasushi Wakahara

Yasuhiro Yamazaki

Yasuo Fukata

Yasuhiro Yamasaki

Yasuhiko Niiro

Kitsutaro Amano

Toshio Takahashi

Hitoshi Yamamoto

Takaya Yamamoto

Hiroharu Wakabayashi

Yoshihiro Ejiri

Yoshinori Mimura

Tasaku Wada

Taiichiro Nakai

Makoto Nunokawa

Yasuo Hirata

Shizuo Suzuki

Akira Ogawa

Yoshihiko Yamazaki

Teruji Watanabe

Takasuke Fukui

A semiconductor light amplifier having an active layer performing a light amplification function, in which the light amplification is performed intermittently by a stable clock timing synchronized with the clock timing of an input light pulse train to the active layer.

Semiconductor light amplifier

A satellite repeater for a digital satellite communication system for use on board of satellites. Receivers are provided with respective antennas for receiving radio-frequency signals from a plurality of ground stations. A signal processing circuit switches signals received in synchronism with stable clock timings. Transmitters receive the switched outputs of the signal processing circuit to provide radio-frequency signals for transmission through respective antennas of the transmitters. Timing detectors receive the outputs of the receivers and detect the frame timings of the output signals of the receivers. Signal storage circuits are provided between respective outputs of the receivers and the signal processing circuit for storing the respective output signals of the receivers by respective amounts. Control circuitry connected to the timing detectors, the signal storage circuits and the signal processing circuit control the storage operations of the signal storage circuits so that each of the frame timings of the received signals and the switching timing of the signal processing circuit have a desired timing relationship.

Satellite repeater

A submarine optical fiber cable using a low-loss optical fiber as a transmission medium, which is provided with a cylindrical pressure resisting layer composed of an assembly of three equally divided long pressure resisting segments of fan-shaped sections with flat contact planes and having at least one optical fiber in an optical fiber housing space formed in the center of the assembly so as to protect the optical fiber from a high water pressure.

Submarine optical fiber cable

A fiber for optical transmission, in which a core thereof for propagating light is formed of a single crystal of an ionic substance except positive ions having no closed cell electronic structure and positive ions of strong covalency. The ionic substance is a binary system compound, a ternary or more multi-system compound, or a solid solution between a binary system compound and a ternary or more multi-system compound.

Fiber for optical transmission having single crystal core

An optical-fiber submarine cable, in which a combination is provided by a thin, cylindrical pressure resisting sheath, and a reinforcing member of a cross section inserted by the thin, cylindrical pressure resisting sheath so as to divide the circular cross section of the pressure resisting sheath into a plurality of spaces and to have a required withstand pressure; and in which at least one low-loss optical fiber is inserted in each of the plurality of spaces. The combination can be fabricated by separately paying out the reinforcing member and the thin, cylindrical pressure resisting sheath, or by curving inwardly a sheet of tape being paid out.

Optical-fiber submarine cable and manufacturing method thereof

A facsimile signal coding system, in which a facsimile signal is divided into a plurality of scanning line groups each including a predetermined number of scanning lines. A substantially central one of the scanning lines of each group is encoded by a coding method without referring to information of a scanning line adjacent to the central scanning line. Information of the remaining lines above the central scanning line is sequentially encoded upwardly from the central scanning line using information of the just precedently encoded line as reference information. Information of the remaining lines below the central scanning line is sequentially encoded downwardly from the central scanning line using information of the just precedently encoded line as reference information.

Facsimile signal coding system

A method for coding addresses of information change picture elements each having information different from that of the immediately preceding picture element in a facsimile signal obtained by successively scanning an original picture, in which the information change picture elements are classified into deviation change points each having a high correlation to a final reference change point selected from coded information change picture elements, and new change points each having substantially no correlation to the final reference change point. The deviation change points are coded to indicate the direction and length of each deviation thereof from the corresponding final reference change point. The new change points are coded to indicate each distance thereto from the immediately preceding information change picture element.

Method for coding addresses of information change picture elements in

In a facsimile system having a carrier movable linearly in both directions with a read-head and a write head for scanning an original paper and/or a printing paper, the movement of the carrier of the facsimile system in a receiving mode is initiated by the synchronization signal sent from another facsimile system in a transmission mode, thus the operation of the facsimile system in the receiving mode is synchronized with that in the transmission mode, on a start-stop basis. Said synchronization signal is sent from the transmission station to the receiving station for every both way trip of the carrier.

Synchronization system in a facsimile system

A facsimile signal transmission system, in which a coder is provided for coding an input facsimile signal for each information block of picture elements on a predetermined number of scanning lines. A counter is provided for counting the number of bits of each coded output corresponding to the picture elements of the predetermined number of scanning lines. Dummy codes are added to the coded output of the coder to increase the number of bits of the coded output to be larger than a reference bit number predetermined in consideration of the subscanning time at the receiving side in a case where the count result of the counter is smaller than the reference bit number.

Facsimile signal transmission system

A facsimile signal coding method, in which information change picture elements are classified into two kinds of change points according to the information change directions. In case of the information change picture element having an information change from white to black, the relative distance between an instant information change picture element and a reference information change picture element selected from information change picture elements on the same scanning line or at least one immediately preceding scanning line is coded. In case of the information change picture element having an information change from black to white, the distance between an instant information change picture element to be coded and the immediately preceding information change picture element is predicted on the basis of information of a run already coded, so that an error between the predicted value and the run length of the instant run is coded. If the error exceeds the run length of the instant run, the run length of the instant run may be exceptionally coded.

Facsimile signal coding method

A facsimile signal coding system for successively coding runs of black and white signals included in a facsimile signal obtained by scanning an original picture, in which the length and position on a scanning line of the runs of the black or white signal to be indicated by encoded codes are temporarily stored in a memory. Information of the run of the same state signal as an instant run of black or white signal to be coded and close to the instant run is taken out as reference run information from the memory. The length of the instant run of the black or white signal to be coded is predicted on the base of the reference run information. An error between the predicted run length and the length of the instant run of black or white signal to be coded is coded. When the error exceeds a predetermined value, the length of the instant run of the black or white signal may be coded in place of the error.

A system for receiving an input facsimile signal sometimes added with dummy codes for each predetermined number of scanning lines by the use of a decoder for decoding the input facsimile signal for each information block of picture elements on the predetermined number of scanning lines. The number of bits of the input facsimile signal corresponding to the picture elements of the predetermined number of scanning lines is counted by a counter. When the count result of the counter is smaller than a reference bit number predetermined in consideration of the subscanning time of a receiver, the subscanning of the receiver is omitted. In this case, an operation of feeding a recording paper of the receiver may be effected.

Facsimile signal reception system

A signal compression system for efficient transmission of an input binary digital signal, in the form of a binary pulse signal, in which bit polarity reversal is checked after sampling for a predetermined number of bits of the sampled binary pulse signal. In a case of detection of any bit polarity reversal, the sampled binary pulse signal is sent out into a converted output pulse signal for the predetermined number of bits. In a case of non-detection of any polarity reversal, the number of bits or the number of bit blocks having no polarity reversal is coded as a coded pulse signal and sent out into the converted output pulse signal. A coded pulse signal is distinguished, the the converted output pulse signal, from the binary pulse signal by at least one flag bit.

Signal compression system for binary digital signals

A system for coding information change picture elements in a facsimile signal, which is employed for coding the address of each information change picture element assuming information different from that of an immediately preceding picture element on each scanning line. A distance between the information change picture element and a final reference information change picture element selected from the information change picture elements of an immediately preceding scanning line and, if necessary, said scanning line is encoded in a manner to minimize the number of bits of each code word.

System for coding information change picture elements in facsimile signal

A signal combining system employed for transmitting a plurality of pulse signals, in which if binary information of the same polarity is continuously transmitted for a period of time, in comparison with the last bit of the preceding period of time, in a main input communication circuit such as a facsimile circuit, signal combining is effected to insert therein other prestored binary information from another communication circuit. The above signal combining is performed for information blocks, each of which includes at least one sign bit for distinguishing pulse signals of the main communication circuit and another communication circuit from one another.

Growing community of inventors

Yokohama, Japan

Yukio Nakagome