Hitachi, Ltd.

Nuflare Technology, Inc.

Hitachi Communication Technologies, Ltd.

Yosuke Takahashi

Shiro Mazawa

Akihiko Yoshida

Daigo Takayanagi

Koji Watanabe

Kiyoshi Kawamoto

Keiji Usuba

Shigeyasu Kubo

Rintaro Katayama

May Takada

Atsushi Abe

Masashi Yano

Hiroto Nakagawa

Masanori Taira

Yuji Abe

Naruhito Nakahara

Nobuo Ito

Kiminobu Akeno

Norihisa Matsumoto

Hitomi Nakamura

Michio Iguchi

Yuichiro Katsu

Takanori Moritomo

Takashi Itamiya

Yusuke Takemichi

According to one embodiment, a dust-collecting apparatus includes a main body with a first surface on which a back surface of a first electrode is disposed; a fixing unit configured to control attachment and detachment of the first electrode and the main body; a second electrode configured to transfer a voltage to the first electrode; and a control board configured to control a magnitude and a timing of a voltage which is applied to the second electrode.

Dust-collecting apparatus

In a mobile communication system including an access gateway (AGW) comprising a C-AGW for handling control messages and a plurality of U-AGWs for forwarding data packets, the C-AGW is provided with a management table indicating an address of U-AGW to be an endpoint of tunnel, in association with each of mobile station IDs. When a tunnel setup request message including a mobile station ID is received from one of base stations, the C-AGW searches the management table for the address of U-AGW corresponding to the mobile station ID and notifies the base station of the U-AGW address, and if the mobile station ID is not found in the management table, the C-AGW notifies the base station of an address of a particular U-AGW selected out of the U-AGWs, so that the base station establishes a tunnel for forwarding data packets toward the notified U-AGW.

Mobile communication system and access gateway having plural user plane AGWS

A radio communication method in which, when hand-off of the down direction is performed while a radio mobile device subjects one application packet of the up direction to fragmentation to divide the one application packet into a plurality of radio packets and transmits the plurality of radio packets, sequence numbers of radio packets managed by a first radio base station to the plurality of fragmented radio packets of the one application packet even after the hand-off of the down direction is performed and to apply sequence numbers of radio packets managed by a second radio base station to fragmented radio packets of the application packet transmitted subsequently after completion of transmission of the plurality of fragmented radio packets of the one application packet; and making a radio base station accommodation apparatus identify a radio base station and restore data for each radio base station.

Radio communication method, radio mobile device and radio base station accomodation apparatus

A method for, in a radio communication system having at least a content server, plurality of base stations, and plurality of radio terminals, enabling two or more base stations among the plurality of base stations to broadcast or multicast data delivered from the content server to the radio terminals, the method includes: providing a Broadcast Multicast Service (BCMCS) Serving Node between the content server and two or more base stations; the BCMCS Serving Node includes a period number and sequence number into data delivered from the content server and transmits data including the period number and sequence number to the two or more base stations; in case that a synchronization is deviated or data is lost during data delivery from the base stations to the radio terminals, the base stations perform re-synchronization on a basis of the period number and sequence number included in data received from the BCMCS Serving Node.

Synchronous delivery method

In a wireless communications system operating according to CDMA or the like, when one terminal simultaneously performs communication using multiple wireless resources (e.g., multiple carriers), there was a problem that when it was attempted to guarantee network mobility by the same soft handoff system as in the case where communication was performed using only one wireless resource, efficiency suffered from the viewpoint of network forwarding load, processing load and wireless resource occupancy time. Soft handoff termination is judged and soft handoff is forcibly terminated according to whether or not the data rate obtained for all resources on the network side satisfies a requested rate, based on a reception state notification from a terminal concerning wireless resources. By performing this processing, the soft handoff period is shortened, sufficient received strength in the terminal is maintained and terminal mobility is guaranteed, while at the same time network forwarding load, terminal processing load and wireless resource occupancy time are suppressed to the absolute minimum.

Control node in a communication system using multiple wireless resources during a soft handoff

An information transmitting method including; determining, on a basis of a packet error rate from a master station to slave stations, a number of times of multicast transmission in accordance with an expected value of a number of slave stations that transmit a retransmission request, an expected value of a number of retransmitted packets responding to the retransmission request, or a probability that the slave stations receive all packets forming information; notifying determined number of times of multicast transmission to the slave stations; and transmitting, to plural slave stations in multicast, same information formed of plural packets the determined times of multicast transmission.

Information transmitting method and information transmitting system

A base station or packet control apparatus, constituting a wireless access network system to be connected to an IP network via a node apparatus, includes a QoS authorization and admission control function for verifying a first communication quality request received from a wireless mobile station based on communication quality level information assured previously to the wireless mobile station, converting the request into a second communication quality request assured to the wireless mobile station, and converting the second communication quality request into a third communication quality request acceptable to communication resources of the wireless access network, and a QoS admission control function for converting, when a second or third communication quality request is received from another node apparatus connected to another wireless access network on account of handover of a wireless mobile station between node apparatuses, the received communication quality request into a communication quality request acceptable to the communication resources.

Wireless communication system and method for assuring communication quality of packet flow

Disclosed herewith is a wireless system capable of reducing packet sending delay occurrence and packet sending delay jittering at the time of hand-over processing executed therein. In the wireless system, upon estimating occurrence of a hand-over event, a subject mobile station and its base station extend the packet buffering period respectively and furthermore, the base station changes the current burst scheduling method for another. The base station and the mobile station then exchanges messages required to execute the hand-over procedure in a period between when sending of a burst ends and when sending of the next burst begins.

Wireless system, for packet communication between base station and mobile stations

In order to narrow down base stations within the tracking-area-based paging area to ones within a smaller area where the mobile unit may exist in a mobile communication system performing the paging on the tracking-area basis, the mobile communication system has a location registration information database memorizing tracking area information, a last location registration information and a N-th (N is an integer of one or more) location registration information from the last for each mobile unit, calculates statistical data on a movement distance for each mobile unit based on the location registration information memorized in the location registration information database, and performs the paging via base stations included both within an area whose radius is equal to the calculated statistical data on the movement distance and within the tracking area.

Paging-area determination method and call-processing control apparatus in mobile communication system

To realize a handover in which a gateway connecting to the access networks using different protocols is an anchor. In a communication system, the gateway holds a service identifier management table for converting a service identifier of different kind with the protocol into a PDN identifier, and at the time of handover, specifies a session to be held with the user identifier and the PDN identifier, selects the same PDN connected to the movement source, and reassigns the same IP address that has been already assigned at the movement source.

Communication system and method, and gateway

A decryption key for decrypting data from an access node is distributed to an access terminal intending to receive the data. An authentication unit receives a message for terminal authentication including a terminal identifier from the terminal and authenticates the terminal. The authentication unit refers to a content registration table having stored in advance the content type of a content which the terminal can receive, in association with the terminal identifier, according to the received terminal identifier to obtain a corresponding content type. The authentication unit refers to a decryption data base having stored in advance a decryption key and its valid period in association with a content type, according to the obtained content type to obtain a corresponding decryption key and valid period. The authentication unit sends an authentication result and the decryption key and valid period to the terminal or to a packet control unit.

Decryption-key distribution method and authentication apparatus

An aggregation device performs a synchronous processing so that a synchronous delivery may be made from a plurality of base stations through a broadcasting channel. A BSN () gives, when it sends broadcasting data for the synchronous delivery to an AN () and an AN (), a period number and a sequence number are added to the broadcasting data so that the data to be sent from the AN () and the AN (can be synchronously delivered.

The present invention can be achieved by a base station in which a terminal is accommodated and the terminal is communicated with another terminal, and which includes: a data rate operation/management unit which operates and stores a time-averaged data rate Rave of the terminal; a threshold value operation/management unit which obtains a current communication data rate R of the terminal to operate and store R/Rave; and a delay management unit which controls to reduce delay on the basis of the R/Rave.

Base station

A wireless communication system including a wireless terminal, a plurality of base stations and a call processing control unit is disclosed. The wireless terminal, upon reception of the notification information from any of the base stations, judges whether the area included in the notification information is contained in the location registration area list stored in a storage unit, and in the case where the particular area is not so contained, sends a location registration request to the call processing control unit. On the other hand, the call processing control unit creates a new location registration area list based on the area included in the notification information and the neighboring areas, and sends the location registration area list to the wireless terminal thereby to execute the paging process.

Growing community of inventors

Yokohama, Japan

Yosuke Takahashi