Mitsubishi Materials Corporation

Tumoru Nagira

Kazuyoshi Tari

Kenzo Nakamura

Hiroyuki Unoki

Kenichiro Hosobuchi

Akira Shibuno

Hirokazu Unoki

Kenichi Murayama

A push-type information service to a client located within a local network and having only a local IP address becomes possible via a network address converting apparatus. A network address conversion program implementing the network address converting process may be stored on a storage medium. When assignment of an Internet IP address to a client is requested by a host server, an IP address assigning unit assigns an Internet IP address to that client. An address conversion table producing unit produces an address conversion table describing the correspondence between the Internet IP address assigned to the client and the local IP address of the client. An address converter notifies the host server of the assigned Internet IP address. After that, if the host server sends data to the acquired Internet IP address, the address converter converts the destination of the data to the corresponding local IP address of the client by referring to the address conversion table.

Network address converting apparatus and storage medium

Radio communication system for push information delivery

A wireless server system and method for communicating between a user terminal and Internet a wirelessly. It is based on a user terminal having a fixed terminal and a terminal unit so that an Internet connection can be made by way of the terminal unit to an appropriate wireless server. The system has at least one wireless server connected to Internet; and a plurality of wireless station devices connected to the wireless server, and the system communicates wirelessly with the terminal unit of the user terminal; wherein one wireless server within a district of communication range of the wireless station devices is designated as a home server for the terminal unit, and the fixed terminal receives data sent wirelessly from Internet by way of the terminal unit.

Wireless server, system and method

A communication system and a communication method arranged to obtain a diversity effect in mobile communication, to reduce the influence of multipath interference, fading or the like, to perform comparatively simple information communication such as message communication with improved reliability, and to achieve effective utilization of frequencies. A plurality of base stations having receivers are provided around an urban area within base station zones. The base stations repeatedly transmit the same message data. Receiving repeaters are provided in the urban area and small or medium suburban zones. Each receiving repeater relays a signal from a small mobile terminal via an Internet network if the output level of the mobile terminal is so low that direct transmission to one of the base stations is impossible. A 25 kHz frequency band is divided into four narrower bands of 6.25 kHz in one of the embodiments. Of frequencies f , f , f , and f in these bands, frequencies f to f are used for &ldquo;down data transmission&rdquo; from the base stations to a mobile terminal while f is used for &ldquo;up data transmission&rdquo; from the mobile station to one or more of the base stations.

Communication system and communication method with diversity features

A method of checking and acknowledging reception of a message in a two-way radio communication system without causing a reduction in the efficiency of processing the message, a storage medium on which a reception checking and acknowledging program is stored for use in the two-way radio communication system, and a two-way radio communication system and a base station for use in the two-way radio communication system is provided. If message data transmitted by a terminal device is received by a base station via a relay station and an Internet network, the base station generates reception acknowledgment data and transmits it in such a manner that when downstream message data is transmitted toward a plurality of terminal devices, the above-described reception acknowledgment data is added to the downstream message data and the resultant data is transmitted to the plurality of terminal devices.

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Omiya, Japan

Tumoru Nagira