Ntt Mobile Communications Network, Inc.

Ntt Docomo, Inc.

Fumiaki Ishino

Hiroki Morikawa

Motoshi Tamura

Tomoyuki Ohtani

Takaaki Satoh

Hiroshi Kawakami

Shigeo Tanimoto

Akihisa Nakajima

Takatoshi Okagawa

Masatomo Nakano

Yukichi Saito

Ichiro Hayashi

Yoji Osako

Daisuke Akiyama

Disclosed is a mobile communication system including a network constituted of at least one switching center and a plurality of base stations, and a mobile station which communicates with the base stations simultaneously. The system permits varying transmission delay between the switching center and the base stations according to the type of services available to the mobile station. The object of the present invention is to propose a communication which permits varying transmission delay according to the type of service currently employed, and to promptly recover a synchronization state even if an out-of-sync state happens. To attain the object, a memory means (mobile switching center processor) stores transmission delay characteristics corresponding to services which are available to the mobile station. Furthermore, a communication timing setting means (diversity handover trunk) determines the timing of communication for the base stations according to the transmission delay characteristic selected according to the service.

Frame synchronization circuit

A multiplex transmission apparatus is provided that conducts traffic control and discards priority control of an ATM network for transferring IP packets having a plurality of QoS conditions. The multiplex transmission apparatus includes an intermediately generated packet generator configured to generate an intermediately generated packet having second header information 'CID' based on first header information 'DSCP' of the IP packet, a buffer storage configured to store the intermediately generated packet in any of transmission waiting buffers based on the second header information &#x201c;CID&#x201d;, an extractor configured to extract out the intermediately generated packet from the transmission waiting buffers according to the second header information &#x201c;CID&#x201d;, and an ATM cell transmitter configured to load an ATM cell with the intermediately generated packet taken out and transmitting the ATM cell to the ATM network.

Multiplex transmission apparatus and multiplex transmission method for encapsulating data within a connectionless payload

A mobile communication system including a subscriber exchange, an information providing server, a plurality of gateway exchanges (#), (#)and a gateway exchange selection serveris provided, in which transmission paths connecting the subscriber exchangeand the information providing servervia the gateway exchanges (#)and (#)are established. The gateway exchange selection server selects a gateway exchange according to the state of the transmission paths. The subscriber exchangeestablish a path to the selected gateway exchange.

Mobile communication system, gateway exchange selection server and gateway exchange selection method

A mobile communications network and data delivery method in a mobile communications network is provided that can implement connectionless transfer in the mobile communications network, and obviate the need for sending a call control signal for data delivery. An IP address is assigned to each of the nodes of the mobile communications network including routing nodes (a gate node and repeater node, for example) and edge nodes and to each mobile station. A routing node, receiving data including the IP address of a mobile station, carries out routing of the data in accordance with routing information. The edge node that receives the data routed by the routing node, transmits the data to the mobile station corresponding to the IP address of the mobile station added to the data. The IP addresses are also applicable to delivering data to users of the same group, or carrying out control like handover.

Mobile communication network and data delivery method in mobile communications network

A multiplex system for multiplexing packets into ATM cells to be transmitted, which can implement effective use of channels corresponding to irregular traffic qualities in services with various types of quality conditions in an actual environment. In response to a connection establishment request (S ), current required bandwidths B , . . . , Bm are changed to B , . . . , B&prime;m by adding the new connection, which causes bandwidths X , . . . , Xm which are assigned to the channels to be changed. When the desired bandwidth including the requested connection is less than an available bandwidth of the corresponding channel, an assigned bandwidth change processing (S ) is activated to assign new bandwidths in accordance with desired bandwidths. The bandwidth assignment change is carried out by changing ratios of extraction rates of packets from the buffers in the multiplex system.

Multiplex transmission system and bandwidth control method

Micro-frame multiplex transmitter

Growing community of inventors

Tokyo, Japan

Fumiaki Ishino