Hitachi, Ltd.

Nippon Hoso' Kyokai

Hitachi Electronics Co., Ltd.

Hitachi Electronics, Ltd.

Nippon Noso Kyokai

Takehiko Yoshino

Hiroaki Nabeyama

Masaaki Fukuda

Tatsuo Kayano

Michio Masuda

Teruhiro Takezawa

Akio Yanagimachi

Eiichi Sawabe

Takashi Uehara

Hisakichi Yamane

Katsuo Mohri

Osamu Yamada

Yoshizumi Watatani

Tetsuo Yamamoto

A signal editing and processing technique for converting a plurality of continuous signals, especially long term continuous audio signals respectively relating to short term still picture signals, to a transmitting signal in which signal transmission periods and pause periods are provided, having an integer ratio of time duration with each other, wherein other signals, especially the picture signals, should be transmitted. All continuous signals are sequentially converted to digital signals addressed in accordance with relevant continuous signals, and once stored in arbitrary positions of a memory, and then read out in a given multiplexed sequence corresponding to the transmission periods of the transmitting signal. The read out multiplexed digital signals are sequentially stored in another memory, and then read out with a given high speed equal to that of the signal transmission. The digital signals read out with the high speed are stored in still another memory, and then read out repeatedly to form the transmitting signal.

Signal editing and processing apparatus

A transmission system for transmitting a plurality of information signals having arbitrary time lengths through a plurality of transmission channels, wherein at a transmitter end said plurality of information signals are allotted to said plurality of transmission channels in such a manner that in each transmission channel an information signal is followed by other information signal and a control signal comprising an index of an information composed of one or more information signals, a transmission channel or channels through which said one or more information signals are transmitted and one or more timings of transition of said one or more information signals is transmitted in addition to said information signals and at a receiver end a desired information signal is selectively extracted and reproduced under the control of said control signal.

Signal transmission system for transmitting a plurality of information

A multi-level code transmission system for restoring the d.c. component of a received signal by peak-clamping of the peak of the received synchronizing signal to a fixed level so as to establish the synchronization of a receiving end prior to an establishment of synchronization at the receiving end and for effecting pulse-clamping of the reference level of a following received signal after the establishment of synchronization at the timing of a clamping pulse relating to the synchronizing signal. In the case of transmitting a multi-level code signal such as an audio PCM signal together with an analogue signal such as a picture signal alternately, for example in a still picture transmission system, the d.c. level of the received signal is varied due to the low cutoff frequency characteristic of the transmission line, the result of which is the occurrence of a code error in a reproduced code signal at the receiving end. In order to obviate such a code error, the present invention uses two kinds of clamping, i.e., peak-clamping and pulse-clamping before and after the establishment of synchronization at the receiving end, respectively. According to this invention, the multi-level code signal can be reproduced with high fidelity.

Receiver for use in a multi-level code transmission system

A receiver for receiving a composite signal including a multivalue pulse code modulated information signal and a binary pulse code modulated synchronizing signal and for regenerating the information signal. The receiver comprises an identification circuit for the identifying binary pulse code signal and an identification circuit for identifying the multivalue pulse code signal to both of which the received composite signal is supplied. The synchronizing signal is detected and regenerated by using the identified signal identified by the identification circuit for identifying the binary pulse code signal. Also by using the regenerated synchronizing signal, the composite signal is pulse clamped and the pulse clamped composite signal is supplied to the identification circuit for identifying the multivalue pulse code signal and the identification is effected.

Receiver for a still picture broadcasting signal

A synchronizing signal regenerator for regenerating all the required synchronizing signals from a composite signal having a plurality of synchronizing signals having a different repetition period and phase. The composite signal comprises a video signal and a pulse code modulated audio multiplex signal arranged in a predetermined sequence. The composite signal further comprises a first synchronizing signal consisting of a certain predetermined pulse series synchronized with a modulated pulse series of the audio multiplex signal and a second pulse code modulated synchronizing signal including a plurality of other synchronizing signals required for the reproduction of the video signal and the audio multiplex signal. The synchronizing signals are inserted at a certain predetermined portion in the video signal and in the audio multiplex signal. The synchronizing signal regenerator comprises means for reproducing the first synchronizing signal after detecting the insertion position of the first synchronizing signal, a means for reproducing a predetermined part of a synchronizing signal among the second synchronizing signals using the first synchronizing signal as the reference, a means for frequency dividing at least one of the reproduced parts of the second synchronizing signal, and means for synchronizing the frequency divided signal by using the parts of the second synchronizing signal having the same phase as the other second synchronizing signals to be reproduced among said part of the second synchronizing signals.

Synchronizing signal regenerator

A signal transmission system for transmitting programed information such as a programed instruction comprising at a transmitter end circuitry for producing a number of program materials and a control signal which is used at a receiver end to control the manner of sequentially connecting program materials in accordance with a response input of a student to construct at least one significant program. The system comprises at the receiver end circuitry for detecting the control signal, circuitry for extracting desired program materials in a desired sequence with the aid of the control signal in accordance with the response input of the student and apparatus for displaying the extracted desired program materials.

Signal transmission system for transmitting programed information such

A multiplex signal transmission system in which a plurality of information signals, having respectively arbitrary time durations and being arranged in time-serial form, are sequentially divided into a plurality of signal portions by a predetermined time period, said signal portions being successively allocated in time-parallel form to a plurality of transmission channels, each of which has a time duration of said predetermined time period, and being transmitted repeatedly through respectively allocated channels every said time duration, comprises a channel shift means for shifting sequentially the channel allocation of said signal portions at predetermined time periods, and a signal transmitting means for transmitting in time-parallel form said signal portions derived from said channel shift means repeatedly through every preceding channels. Consequently, the transmission line can be efficiently utilized in such a way that, at the sending end, a plurality of information signals having respectively arbitrary time durations are folded into a plurality of transmission channels having given time periods, and besides that, at the receiving end, once a portion of any desired information signal is caught in a corresponding channel, successive signal portions can be derived sequentially from the same channel every said given time periods. Hence, a channel selecting means of a receiver in this system can be simplified.

Growing community of inventors

Yokohama, Japan

Takehiko Yoshino