Abstract: A mobile node (MN) transmits a (4) echo request to the effect that the source address is set to be a new care of address (nCoA) right after transmitting a (3) binding update (BU) for a home agent (HA). The nAR having received the (4) echo request intends to transmit an echo reply to the nCoA being the source address of the echo request. However, at this time, since an entry regarding the nCoA does not exist in a neighbor cache of the nAR, the nAR transmits (5) neighbor solicitation (NS) to the MN, and generates a neighbor cache entry of the nCoA. After this, at the time when a binding acknowledgment (BA) has arrived at the nAR, since the entry of the nCoA exists, the (8) BA and data packets (9) to (11) arriving at the nAR following the (8) BA are transferred to the MN without buffering in the nAR, corresponding to the entry of the nCoA generated at the time of transmission of the (7) echo reply.

Abstract: A scramble code allocation method used by mobile communications systems, and a base station and a mobile station that use the method are disclosed. The scramble code allocation method autonomously and optimally sets up a scramble code unique to a target base station. The method includes a step of generating a collection packet for collecting unique information of surrounding base stations, the unique information being used for setting up respective identifiers of the surrounding base stations; a step of broadcasting the collection packet to the surrounding base stations through a network; a step of receiving response packets from the surrounding base stations in response to the collection packet; a step of extracting the unique information of the surrounding base stations inserted in the response packets that are received; a step of storing the extracted unique information; and a step of setting up an identifier of the target base station based on the stored unique information.

Abstract: A mobile node (400) capable of establishing an ad hoc network routing is disclosed. The mobile node comprises a transmitting/receiving unit (426) for communicating with other communication unit and a routing request generator (422) for generating a routing request message for requiring an ad hoc network routing. The mobile node further comprises: an address storage (427) for storing an address of the mobile node (400) and an address of a receiving node; a random number generator (430) for generating a random number; a certificate issuing unit (440) for issuing a certificate of the mobile node (400); a digital signature creator (450) for creating a digital signature of the mobile node (400); and a controller (424) for transmitting/receiving the routing request message accompanied by the address of the mobile node, the address of the receiving node, the random number, the certificate and the digital signature via the transmitting/receiving unit, according to an ad hoc network protocol.

Abstract: In a radio communication system where, concerning the maximum allowable delay and the reception error rate as required values for QoS, a first mobile station group of which the maximum allowable delay is less than a reference value and the reception error rate is a reference value or more, and a second mobile station group of which the maximum allowable delay is a reference value or more and the reception error rate is less than a reference value coexist, the base station sets the transmission power margin for a mobile station of the first mobile station group to be higher than the transmission power margin for a mobile station of the second mobile station group, and a mobile station of the first mobile station group sets the transmission power margin to be higher than the transmission power margin of a mobile station of the second mobile station group.

Abstract: A base station is disclosed. The base station includes: a service area status determination unit configured to determine status of a service area of the base station based on received signals from mobile stations; a total transmission power determination unit configured to determine status of total transmission power of the base station based on total transmission power of surrounding base stations; a transmission power determination unit configured to determine transmission power of a common control channel of the base station based on the status of the service area and the status of the total transmission power; and a transmission power setting unit configured to set the transmission power determined by the transmission power determination unit.

Abstract: A system is provided in which capacity and satisfaction rate with a quality of service in packet communications performed through a radio link established between a transmitting station and a receiving station is improved by dynamically limiting transmission power of packets in the transmitting station and keeping an increase of an interference level in the receiving station, which belongs to another cell, within a TPC margin. The present invention includes a resource allocator configured to set transmission power of packets in a next step period, by use of transmission power of packets in a preceding step period (slot) and an interference level of the receiving station.

Abstract: In a mobile communication system having a plurality of radio base stations and a mobile station, a radio base station selection method in which a radio base station to start communicating with a mobile station is selected from among adjacent radio base stations capable of communicating with the mobile station is provided. The method includes the steps of requiring, by a radio base station in service, a radio channel availability report from each of adjacent radio base stations indicated by the mobile station, in response to a signal for requesting connection to the mobile station; selecting a radio base station to be connected to the mobile station, based on the radio channel availability reports obtained from the adjacent radio base stations; and notifying the mobile station of information necessary for communicating with the selected radio base station.

Abstract: A scramble code allocation method used by mobile communications systems, and a base station and a mobile station that use the method are disclosed. The scramble code allocation method autonomously and optimally sets up a scramble code unique to a target base station. The method includes a step of generating a collection packet for collecting unique information of surrounding base stations, the unique information being used for setting up respective identifiers of the surrounding base stations; a step of broadcasting the collection packet to the surrounding base stations through a network; a step of receiving response packets from the surrounding base stations in response to the collection packet; a step of extracting the unique information of the surrounding base stations inserted in the response packets that are received; a step of storing the extracted unique information; and a step of setting up an identifier of the target base station based on the stored unique information.

Abstract: A packet transmission method in which packets are transmitted between a base station and a mobile station communicating with the base station includes the steps of: recognizing the size of each of the packets to be transmitted; determining a transmission rate for each packet in accordance with the recognized size of the packet; allocating a radio resource to the transmission of each packet between the base station and the mobile station based on the determined transmission rate; and transmitting each packet between the base station and the mobile station using the allocated radio resource. In the method, a modulation method or a radio resource used for transmitting the packets is determined by calculating a transmission rate in a wireless area according to the size of each packet and a transmission request in the wireless area.

Abstract: A packet transmission system is provided to achieve a higher throughput in downlink packet transmission to a mobile node. When there is a packet call directed to the mobile node, a transmission node in a network in this packet transmission system retrieves information as to a connection point of the mobile node from a distribution location information holder of a home agent. Packets are inputted to a packet distributor situated at the logical location designated by the retrieved connection point information. The packets are then distributed by the packet distributor to radio transmission devices, and are transmitted at once.

Abstract: An object of the present invention is to enable the improvement of Qos and efficient use of resources with regard to the entire system by performing resource control of an own cell in cooperation with that of peripheral cells. The present invention provides a resource control system used for packet communication between a mobile station and each of a first and a second base stations. The first base station includes the judgment unit for judging whether or not the Qos of a packet to be communicated with the mobile station is ensured in the packet communication with the mobile station, or judging whether or not the resources necessary for a packet to be communicated with the mobile station are secured; and the second base station interface for requesting the second base station to suppress the use of resources when the Qos is judged not to be ensured, or the necessary resources are judged not to be secured.

Abstract: In a mobile communication system 1 having a radio base station 2, and mobile stations 5, 6 configured to communicate with the base station 2 and segmented into a plurality of mobile station groups, the base station 5 provides a broadcast channel with first instruction information to notify the mobile station 5 of whether or not to receive the broadcast channel, provides a paging channel with second instruction information to notify the mobile station 5 of the presence/absence of paging information, and performs such a channel transmission control as to intermittently transmit the broadcast channel and the paging channel on a control channel.

Abstract: A mobile node having two or more interfaces, a control method of the mobile node, and a mobile node control program are disclosed. The mobile node includes a generating unit to generate control information for each interface, an information providing unit for providing the control information provided by each interface to an upper layer, and a routing controlling unit to perform at least one of determining connectivity, and updating a routing based on the provided control information.

Abstract: In a disclosed mobile communications system wherein packet communication between a base station and its subordinated mobile station is established based on a reservation packet, the packet communication uses controlled transmission power and a radio resource allocated based on reception quality information received from the mobile station.

Abstract: In a state I, a link layer of a mobile host is connected to an access router and a default router is set to the access router such that data packets (P1) and (P2) reach the access router and are routed to a correspondent host. In states II and III, data packets (P3) to (P8) are not transmitted but are buffered. When the mobile host switches the default router from the access router to an access router upon reception of a router advertisement from the access router, processing moves to a state IV and the buffered data packets (P3) to (P8) are transmitted. Since the link layer of the mobile host is connected to the access router and the default router is set to the access router, the data packets (P3) to (P8) reach the access router and are routed to the correspondent host.

Abstract: A base station includes: an acquisition unit for acquiring a quantity of stored packets from a mobile station, the quantity of stored packets being stored in a buffer for storing the packets transmitted by the mobile station; a radio resource controller for allocating priority radio resources preferentially usable by the mobile station to a radio channel for the mobile station, and for allocating usable radio resources allowed to be used by the mobile station from the priority radio resources to the mobile station by use of the quantity of stored packets acquired by the acquisition unit; and a result notification unit for reporting a result of the allocation by the radio resource controller to the mobile station.

Abstract: When a mobile node MN moves from an access router AR3 to another access router AR4, it sends a multi-binding on request to a mobility agent MA1 and then moves ({circle around (1)}). Receiving the multi-binding on request, the mobility agent MA1 voluntarily configures prospective CoA's (probable CoA's) The probable CoA's are added as forwarding addresses while an M bit is set on in an register of the mobile node MN on a binding cache ({circle around (2)}). When the mobility agent MA1 receives a capsuled packet addressed to the mobile node MN thereafter, it tunnel-forwards the packet to CoA3, probable CoA2, and probable CoA4 according to the binding cache ({circle around (3)}).

Abstract: A packet transmission system includes a home agent providing a home link and a home address to a mobile node, one or more access routers, each providing a foreign link and a c/o address to the mobile node, and one or more mobility support routers that relay a packet to the destination between the mobile node and the home agent or a counterpart correspondent node. When the mobile node moves into a new foreign link, the corresponding access router transmits a registration request to the home agent and/or the correspondent node. When acquiring a registration request on the way to the destination, each mobility support router stores an entry having the home address of the mobile node and the c/o address contained in the registration request, and produces and transmits a new registration request updating the c/o address to its own address.

Abstract: An object of the present invention is to decrease a care-of address update duration in switching of a link used for connection to an IP network by a mobile node (MN). MN acquires a list of access routers (ARs) existing on neighboring links to the link used for connection by the mobile node and creates a list of care-of addresses (CoAs) corresponding to the respective ARs entered in the list, each CoA being used as a destination of MN at a link on which an AR corresponding thereto exists. After the change of the connected link, MN acquires a data link layer address of AR existing on the link after the change and detects a default router on the basis of the address with reference to the access node list. Furthermore, MN detects a CoA with a network prefix corresponding with a subnet prefix of the default router, as a primary CoA and requests MAP to register a binding between the primary CoA and HoA.

Abstract: An apparatus is adapted to configure a virtual communication device that includes communication devices accessible to the apparatus. A signal interface receives from a calling communication device information data including first and second content parts, and an information separating unit separates the first and second content parts of the information data. A DMF unit identifies communication attributes of the communication devices accessible thereto and identifies the communication devices capable of processing information corresponding to at least one of the first and second content parts.