Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electric Corporation

Yukiyasu Kawahata

Tomohiro Kimura

Fumitaka Ono

Hiroshi Honma

Makoto Matsumoto

Takayoshi Semasa

Susumu Oka

Yukinari Matsuda

Morio Yoshimoto

Yoshihiko Yamamoto

A transmission system that can continue communication even if a tracking error exists and to reduce interference on other transponders when transmitting a video and audio between an endstation facility and another endstation facility via a transponder mounted on communications satellite. This transmission system includes a tracking antenna that tracks a transponder, a tracking error calculation circuit that obtains a tracking error in a tracking operation of the tracking antenna, a transmission level control circuit that obtains a transmission level of a signal in response to the tracking error, and a transmitter that transmits the signal at the obtained signal level via the tracking antenna to the transponder of the communication target.

Communication device, communication method, and a computer-readable recording medium

Communication is performed without paying attention to the fact that the communication is executed between multimedia terminals having communication procedures differing from each other. A terminalstarts a communication procedure that is necessary to establish a communication path to a communication service unit, in order to execute communication with a multimedia terminal; when a communication protocol conversion unitreceives communication start request from the terminal, the communication service unit executes identification process of a calling terminal based on the identification number, which exists in communication start request, for determining the multimedia terminal, and inquires a terminal information managing unitof the calling terminal. The terminal information managing unitretrieves terminal information related to the calling terminal based on a terminal information request, and informs of the retrieved terminal information to the communication protocol conversion unit. The communication protocol conversion unitinforms of the communication start request to the terminalwhen the transmitting the terminal information of the terminalis obtained, and continues a relay process in communication procedure, which is necessary for following establishment of a communication path.

Communication service unit and connection sequence operating method

Encoding and decoding devices which are capable of increasing the encoding and decoding speed. In arithmetic encoding, there is a possibility of encoding with high efficiency which is very close to the entropy of the information source, but the encoding and decoding time is generally longer than that in another encoding systems such as an MMR encoding system. For example, in a standard facsimile equipment, about 1.3 sec is required for encoding the picture information in an A4-size copy. In prediction encoding, a memory for storing the past reference symbols and the predicted values therefor is necessary for prediction. Since the memory capacity is generally large, a large-capacity RAM is used. The encoding time is therefore greatly dependent on the access speed of the RAM. In the present invention, a high-speed register for storing the predicted value for a special symbol pattern is provided separately from the RAM so that the predicted value of the special symbol pattern is read from this register, thereby enabling high-speed encoding.

Encoding and decoding devices with predictor and detector

Growing community of inventors

Tokyo, Japan

Yukiyasu Kawahata