Fujitsu Corporation

Tatsuru Nakagaki

Tetsuo Tachibana

Toshio Irie

Ryoichi Ishibashi

Masayuki Yamanaka

Katsutoshi Inoko

Toshiyuki Hijikata

Hiroyuki Suzuki

Takashi Hatano

Tetsuo Tomita

Tetsuo Nishino

Yuki Shinada

Ryuji Hyodo

Daisuke Nitta

Tomonori Kumagai

Toshimasa Fukui

Kenji Nemoto

Kosuke Nobuyasu

Akihiro Kobayashi

Takeshi Shimada

Katsumi Omuro

A mobile terminal includes a reception unit to receive, from at least one of a plurality of communication systems, an initial beacon containing information for establishing communication according to each of the plurality of communication methods, a request unit to generate a request by use of the initial beacon to transmit the request to the at least one of the plurality of communication systems, and a determination unit to determine, based on information as a response to the request, the communication method and the frequency band, which are to be used in a time zone by the mobile terminal.

Mobile terminal

Data transmission for writing data into a shared memory is performed by a high-speed dedicated line provided between each processor and the shared memory. When a processor performs writing to a shared memory space, the processor notifies an update notification bus corresponding to the conventional global bus, to which address the update is to be performed. The other processors which have detected this notification inhibit access to that address and wait for the write data to be sent to the address via the dedicated line. When the data has arrived, the data is written into the corresponding address. Here, the data is also written into the corresponding address, thereby maintaining the cache coherency. Moreover, when transmitting a write address, it is necessary to acquire the bus use right while data transmission is performed by using the dedicated line, which significantly reduces the time required for acquiring the bus use right.

Multi-processor system

When vocoder-bypass communication is performed between a first mobile station on a voice transmitting side and a second mobile station on a receiving side, the first mobile station transmits voice data the compression rate of which has been reduced periodically. As a result, a vacant space is reserved periodically in a traffic frame transmitted from a base station controller on the receiving side to the second mobile station on the receiving side. When it becomes necessary to transmit signaling data, a signaling multiplexer of the base station controller transmits the signaling data upon multiplexing it into the vacant space of the traffic frame.

Signaling communication method of mobile communications system

A wireless communication system having base station equipment which forms a wireless zone and base station control equipment which performs channel control of calls occurred in the radio stations located in the wireless zone, in cooperation with a switching center. The base station equipment extracts a specific speech signal that has control information included in speech signals generated by a variable rate codec. The base station equipment disassembles the speech signals and the control information into individual transmission units and transmits the transmission units to the radio base station. The base station radio control equipment outputs or accepts control information including identification information, and performs delivery of the control information between the radio station and the switching center.

Base station equipment and base station control equipment

A base-station host system achieves high-speed routing to reduce a burden on a controller which carries out a routing process, and receives a cell containing a plurality of packets (an ATM cell of AAL Type 2) from a base station. A cell containing a plurality of packets is transmitted from the base station to the base-station host system. A packet extracting unit extracts the packets from the received cell. A cell generating unit generates an internally processable cell based on information carried by the payload of a packet. A switch unit switches internally processable cells depending on routes thereof. For reverse communications, internally processable cells are sent from the switch unit to a packet generating unit. The packet generating unit generates packets based on information carried by the payloads of the internally processable cells. A cell transmitting unit collects a plurality of packets designed for the same base station, generates a cell containing those packets, and transmits the generated cell to the base station.

Host system for base station

By transmitting an analog CATV signal output from a CATV-HE (CAble TeleVision-Head End) to an HDT (Host Digital Terminal), an analog transmission channel for transmitting the analog CATV signal to an ONU (Optical Network Unit) is included in a path housing a digital transmission channel for transmitting a digital service signal for individual distribution service to the ONU. Furthermore, a digital service signal for multicast service is modulated and converted into an analog service signal by a modulator in the HDT. Then, the converted signal is mixed with the analog CATV signal, and transmitted to the ONU. Accordingly, each of the ONUs is equipped with only a built-in modulator for modulating the digital service signal for individual distribution service.

Mixed analog-digital service distribution system and method

Information selectively read out from an information source storing various types of information is repeatedly sent from a center office to a number of terminal equipment units with an error check code added on. The terminal equipment units use the error check code to detect if there is an error in the received information. If the information is received without error, the reception operation is ended for each terminal equipment unit. In this case, there is no interposition of a protocol for confirming if the transmission and reception of the information had been performed normally, so the load on the center office is lightened and it is possible for each of the terminal equipment units to receive the information without error.

Information broadcasting system confirming the reception of information

CPCS-UU in the CPCS-PDU trailer defined by the AAL Type 5 in an ATM network is used as a sequence number for error handling. CPCS-UU in the CPCS-PDU trailer is used as a sequence number of an MPEG-2 transport stream packet contained in CPCS-PDU; by monitoring the number of packets, and based on the check results of CRC-32, LI, and cell count, error handling is performed at the receiving end, and for corrupted packets, null packets are inserted in place of the corrupted packets.

Error handling in transmission of data that cannot be retransmitted

A media information distribution service system, such as a video-on-demand service system, is disclosed which, even if the capacity of a line is small and the number of lines connected to a media server, such as a video server, has to be increased accordingly, permits an uneconomical increase in the number of line circuits in the media server to be checked. In the system, a subscriber group that a distributor accommodates can be associated with a plurality of distributor-side paths on a distributor-side line. Each of the distributor-side paths is connected to a respective one of server-side paths on separate server-side lines connecting the media server and an exchange. In sending media information to a subscriber group, an in-server path control unit installed in the media server is permitted to select a free one out of server-side paths on server-side lines allocated for that subscriber group and activates a line interface corresponding to the free server-side path.

Media information distribution services system and method

A broadband integrated services digital network includes a network, first and second terminals, and first and second terminal adapters. Each of the first and second terminal adapters includes a buffer storing a predetermined number of bursts of data from either the first or second terminal and storing a predetermined number of bursts of data from the network, and a first part for sending ready notification information to the network and for receiving the ready notification information from the network. The ready notification information shows that the buffer has an available storage capacity equal to at least one burst. Each of the first and second terminal adapters further includes a second part for sending ready information to the corresponding one of the first and second terminals before the first part receives the ready notification information from the network. At least, one burst is written into the buffer each time the ready information is sent.

Adapter monitoring storage capacity of its buffer and sequentially

A packet data is formed of a plurality of ATM cells. When cells of the packet data are lost, especially if the packet data is an image or picture signal including synchronous signals, it becomes difficult to reproduce the image or picture on a receiving terminal. A data length compensating device compensates the lost cell. In order to deal with the lost cells lying over between two packets, a data length compensating device includes a lost cell detecting circuit which detects a lost cell to be included in the data according to the sequence number of the plurality of cells, compensation control circuit which outputs compensation information including the number of lost cells to be compensated, and inserting circuit inserts dummy data corresponding to the lost cells to be compensated based on the compensation information.

Data length compensating device for compensating lost cells in packet

Information broadcasting system having reception error minimizing

A broadband integrated services digital network includes a network, first and second terminals, and first and second terminal adapters. Each of the first and second terminal adapters includes a buffer having a capacity for storing a predetermined number of bursts of data, as received thereby from the respective first and second terminals, and for storing a predetermined number of bursts of data, as received thereby from the network, and a first part for sending ready notification information to the network and for receiving the ready notification information from the network. The ready notification information shows that the buffer has an available storage capacity equal to at least one burst. Each of the first and second terminal adapters further includes a second part for sending ready information to the corresponding one of the first and second terminals before the first part receives the ready notification information from the network. At least one burst is written into the buffer each time the ready information is sent.

Method and apparatus for controlling the flow of data transmissions by

In a call disconnection method and a system for executing the same in an ATM (Asynchronous Transfer Mode) network, a plurality of timers are provided corresponding to each call in an exchange of an ATM network. A connected call is detected, and a data cell is not transmitted for longer than a predetermined time, by using the corresponding timer, and disconnecting the detected call from the ATM network.

Call disconnection method and exchange executing the same in ATM network

In an accounting system in a B-ISDN offering video programs to a plurality of subscriber terminals coupled thereto, a timer, and an account controller are provided in each of the subscriber terminals. The timer starts to count time when a subscriber terminal receives a video program offered from the network. The account controller determines whether or not a count time in the timer has reached n sec. (e.g. 300 sec.), and transmits account starting information to the network when it is determined the count time in the timer has reached n sec.. The account controller also transmits account termination information to the network when the subscriber terminal discontinues receipt of the video program. The network is provided with an accounting unit for performing a accounting process with respect to each of the subscriber terminals from which the account starting information and the account termination information are transmitted, the accounting process starting from a time at which the network receives the account starting information to a time at which the network receives the account termination information.

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Kawasaki, Japan

Tatsuru Nakagaki