Fujitsu Corporation

Other

Ntt Docomo, Inc.

Satoru Chikuma

Nobutsugu Fujino

Masanaga Tokuyo

Hideto Furukawa

Takeshi Inoue

Tamio Saito

Takashi Kimoto

Atsushi Yamashita

Takashi Nishigaya

Tetsuyoshi Takenaka

Yuichiro Noguchi

Itaru Nakagawa

Ikuo Takekawa

Takeshi Saito

Teruhiko Onishi

Morihisa Kawai

Gorou Sekiguchi

Daisuke Kuwata

Michiyasu Chikada

Takanori Hisanaga

Tetsuya Taniguchi

Upon receipt of a request to connect to an ad-hoc network from an external communication node, an address assigning unit obtains information on an IP address assigned to the external communication node. The address assigning unit determines whether the IP address is already used by any of communication nodes that are connected to the ad-hoc network based on network management information stored in a storage unit. The address assigning unit generates a new IP address that is used none of the communication nodes when the IP address is already used, and transmits the new IP address to the external communication node. The external communication node is assigned the new IP address, and connects to the ad-hoc network.

Address assignment apparatus, address assignment method, and computer product

In a mobile communicating system, a mobile terminal has a position information detecting unit detecting position information, a position information transmitting unit transmitting position information to an information center, an up-load data transmitting unit transmitting up-load data to the information center and an information/service utilizing unit utilizing information/service from the information center. The information center has an accumulating unit accumulating information/services, a retrieving unit receiving the position information from the mobile terminal to retrieve the information/services in the accumulating unit, an accumulation controlling unit accumulating the up-load data in the accumulating unit, and an information/service transmitting unit taking out the information/service retrieved by the retrieving unit from the accumulating unit and transmitting it to the mobile terminal, thereby providing not only map information showing the current position of the mobile terminal but also information of facilities on the map to the mobile terminal.

Mobile communicating system, and a mobile terminal, an information center and a storage medium used therein

A communication network switching device is provided between a client and a server as a intermediary mechanism to estimate a traffic and to issue a switching request for communication networks. Two switching devices include units for releasing a session in cooperation with each other and units for resuming the session in cooperation with each other. The client switching device includes a unit for connecting to a communication network to which the communication is to be switched after the session release is complete and for acquiring a new communication address assigned through the connection and a unit for notifying the server switching device of the acquired communication address. The server switching device includes a unit for identifying a server pointed to by a port number specified in a service request to transfer the service request and a unit for acquiring the new communication address acquired by the client switching device.

Wireless data communication network switching device and program thereof

When voice communications are to be established using the telephone having the telephone number displayed on the application during the data communications, a temporary line disconnection unit disconnects a line being used for the data communications. The application is not notified of this, and the line is connected between the terminal and the telephone. The user on the mobile computer side can voice-communicate with the user of the telephone using the terminal. When the voice communications terminate, the temporary line disconnection unit connects the line between the fixed computer side and the mobile computer side to resume the data communications. Since the application is not notified of the temporary disconnection of the line, the session is set active and the data communications are not started from the very beginning.

Communications system and communications method

An apparatus for use in a radio communication system, comprising a monitoring unit which monitors whether or not a transmission request for data, designating the particular apparatus itself as a transmission destination, has been issued by the particular apparatus or another apparatus connected thereto through a network; a generation unit which operates when the monitoring unit has detected the issue of the transmission request, to generate a process to serve as a reception destination for the data and also to generate a buffer in correspondence with the process; a transfer unit which transfers the data from a transmission request source to the process in accordance with communications of virtual circuit type, so as to store the data in the buffer; and a transmission unit which transmits the data stored in the buffer, to the other apparatus through a radio channel. Thus, enhancement in the throughput of end-to-end data communications can be realized.

Radio communication system and apparatus, communication method and program recording medium therefor

When a plurality of IP packets to be relayed, which form a TCP connection, pass through a router device, converting units rewrite part of IP address information and port number information within the packets according to a predetermined rule in cooperation with a TCP connection management database. A stream linking unit extracts the information indicating the original connection destination of a TCP connection from the packets, and links two TCP connections with streams. Converting units rewrite part of the IP address information and the port number information within a plurality of packets to form a TCP connection with an original connection destination according to a predetermined rule in cooperation with the management database.

IP router device having a TCP termination function and a medium thereof

In a mobile communicating system, a mobile terminal has a position information detecting unit for detecting position information, a position information transmitting unit for transmitting the position information to an information center, an up-load data transmitting unit for transmitting up-load data to the information center and an information/service utilizing unit for utilizing information/service from the information center, whereas the information center has an accumulating unit for accumulating information/services, a retrieving unit for receiving the position information from the mobile terminal to retrieve the information/services in the accumulating unit, an accumulation controlling unit for accumulating the up-load data in the accumulating unit, and an information/service transmitting unit for taking out the information/service retrieved by the retrieving unit from the accumulating unit and transmitting it to the mobile terminal, thereby providing not only map information showing the current position of the mobile terminal but also information of facilities on the map to the mobile terminal.

Mobile communication system, and a mobile terminal, an information

A network control system for eliminating a relative error among control signals transmitted from nodes provided in radio zones respectively, a mobil station moving among the radio zones, each of the nodes comprising: a relative error detecting unit for detecting a relative error between an after-controlled transmitting control signal to be transmitted to adjacent nodes and a received control signal from an adjacent node; and a control unit for controlling a before-controlled transmitting control signal in such a way that the relative error becomes zero so as to output the after-controlled transmitting control signal.

Network control system for controlling relative errors between network

A network control system for controlling a plurality of nodes respectively corresponding to, and provided in, a plurality of radio zones. Each node has a corresponding base station, where a mobil station travels among the plurality of radio zones and communicates with the base station of a respective node when travelling in a radio zone corresponding to the respective node. Each base station transmits a transmission signal for the corresponding node to adjacent nodes, receives transmission signals transmitted from the base stations of adjacent nodes and spatially filters the received transmission signals. Each base station includes (a) a notification unit notifying the base stations of adjacent nodes of transmission timing information of the transmission signal of its own node, and (b) a correction unit receiving transmission timing information from the base stations of adjacent nodes indicating the timing of the transmission signals of the adjacent nodes, and correcting the timing of the transmission signal of its own node to minimize a difference between the timing of the transmission signal of its own node and the timing of the spatially filtered transmission signals received from the base stations of the adjacent nodes.

A network control system for controlling a plurality of nodes respectively corresponding to, and provided in, a plurality of radio zones. Each node has a corresponding base station. A mobil station travels among the plurality of radio zones and communicates with the base station of a respective node when travelling in a radio zone corresponding to the respective node. Each base station transmits a transmission signal to adjacent nodes and receives transmission signals transmitted from the base stations of adjacent nodes. Each base station includes (a) a reception automatic frequency control unit receiving the transmission signals transmitted by base stations of adjacent nodes, and performing an automatic frequency control operation for each received transmission signal, (b) a frequency error detection unit detecting a frequency error between the automatic frequency controlled transmission signals and a frequency obtained by adding a nominal frequency gap between base stations to the transmission frequency of the transmission signal of the node corresponding to the frequency error detection unit, (c) an averaging unit spatially filtering the frequency errors to produce a spatial mean value, and (d) a transmission frequency control unit controlling the transmission frequency of the node corresponding to the transmission frequency control unit in accordance with the spatial mean value, to substantially eliminate the frequency errors.

Growing community of inventors

Kawasaki, Japan

Satoru Chikuma