Nec Corporation

Masanori Taketsugu

Yukitsuna Furuya

Kojiro Hamabe

Toshihito Kanai

Kazutomo Kobayashi

A newly developed IP layer technology can be applied to a wireless access network without a wireless base station adding or amending the new IP layer technology to a wireless region specific signal. The wireless base station transfers to a wireless access gateway a communications establishment request signal from a mobile terminal without conversion. When the mobile terminal which is the source of the communications establishment request signal is not permitted to communicate with equipment external to the wireless access network, the wireless access gateway transfers the communications establishment request signal to an access network control station. The access network control station continues communications with the mobile terminal, determines whether or not the communications between the mobile terminal and equipment external to the wireless access network is to be permitted based on the communications between the access network control station and the mobile terminal. When the communications between the mobile terminal and the equipment external to the wireless access network is permitted, it transmits a communications establishment permission signal to instruct the wireless access gateway to establish a channel between the mobile terminal and the equipment external to the wireless access network.

Wireless access control method and wireless access system

In a mobile communication system, a mobile terminal can designate a communication quality in requesting communication. A radio base station is connected to the mobile terminal through a radio channel. A radio network controller is connected to the radio base station to control the communication quality between the mobile terminal and the radio base station. The radio network controller includes a communication request reception determination unit. Upon receiving a communication request which designates the communication quality from the mobile terminal, the communication request reception determination unit determines whether the received communication request is to be received, on the basis of a communication quality provided to communication which requests without communication quality.

Mobile communication system

A mobile communication system implementing a packet communication by allocating efficiently a transmission capacity to a wired line and a wireless line wherein an practical transmission speed of a data communication between a radio base stationand a mobile terminalis measured in every call, a transmission capacity required for transmitting data of the transmission speed at the minimum level is determined as a target transmission capacity and in a relay stationand a mobile switching stationa permissible transmission capacity with which transmission of data is permitted in the wired line is allowed to decrease in the case where the permissible transmission capacity is larger than the target transmission capacity, while the permissible transmission capacity is allowed to increase in the case where the permissible transmission capacity is smaller than the target transmission capacity, whereby a transmission speed in the wired line is controlled so as to be equal to or less than the permissible transmission capacity.

Method for controlling transmission capacity and mobile communication system

A mobile communication system includes a mobile terminal, a radio access network, and a home agent. The radio access network includes a radio base station which carries out packet communication with the mobile terminal through a radio channel, and a radio channel control station which controls the radio base station. The home agent stores data transmitted from said mobile terminal and associated with a current position of said mobile terminal. The packet communication between the mobile terminal and the radio channel control station is controlled based on radio channel control of packet switching connection. The packet communication from the core network to the radio channel control station is controlled based on mobile IP (mobile Internet Protocol).

Mobile communication system with packet effectively transmitted and control method for the same

A transmission control method is provided which can improve a decrease in throughput when collision occurs during the use of a collision-based access system. In response to forward link message DA (I, ) from a radio base station , a terminal transmits a packet signal D ( ) while a terminal transmits a packet signal D ( ). When the packet signals collide head-on, the radio base station does not receive them but transmits forward link message D (I, ). When the terminals and receive the forward link message, they judge that the packet signals transmitted by themselves have collided head-on and then transfers to a back-off state in which random time transmission is sustained. When forward link message DA (I, ) is received from the radio base station , the terminal restored from the back-off state retransmits the packet signal D ( ). Meanwhile, the terminal is changed to a back-off state when receiving forward link message DA (P, ) from the radio base station . The terminal does not originally transmit a packet signal but retransmits the packet signal D ( ) because transmission request from the radio base station.

Transmission control method

A mobile terminal ( ) receives pilot channels from both of radio base stations ( and ) when it is located in a boundary region between radio zones ( and ). Upon call origination, the mobile terminal ( ) calculates a propagation loss (Ptx &minus;Prx ) given by a difference between transmission power level information (Ptx ) stored in the pilot channel of the radio base station ( ) and a reception field strength (Prx ) actually received. Likewise, the mobile terminal ( ) calculates a propagation loss (Ptx &minus;Prx ) as a difference between transmission power level information (Ptx ) stored in the pilot channel from the radio base station ( ) and a reception field strength (Prx ) actually received. Then, the mobile terminal ( ) compares the propagation losses calculated for the radio base stations ( and ). A call is originated to one of the radio base stations ( and ) which has a smaller value in the above-mentioned comparison.

Call control method in mobile communication and system therefor

A transmission control system for performing one-to-multiple site data transmission by a radio packet communication, comprising a plurality of communication terminals and a communication base station for determining timing of access control as well as timing of sending and receiving transmission data, the communication terminals and the communication base station being connected via a radio packet communication system, in which the communication terminal sends a negative acknowledgment signal on the failure in receiving a packet signal sent from the communication base station, the communication base station resends the packet signal which is not received by the communication terminal upon receipt of the negative acknowledgment signal, and the communication terminal sending the packet signal resends the packet signal which was sent just before, upon receipt of the packet signal resent from the communication base station.

Data transmission control system for performing one-to-multiple site

To enable data transmission without transmitting packer's serial numbers, a transmit serial number is incremented by one at a transmit site each time a serial numberless data packet is sent to a receive site, and a copy of the transmitted packet is stored in a transmit memory corresponding to the transmit serial number. The process is repeated so that a predetermined number of outstanding packets are transmitted. At the receive site, a receive serial number is incremented by one upon receipt of each packet and the packet is stored in a receive memory corresponding to the receive serial number. The receive site determines whether there is an error in the outstanding packets in the receive memory. If an error is found, the receive site sends a request packet containing the serial number of the packet in error to the transmit site. In response, the transmit site sends a replacement copy for the corrupted packet to the receive site which, in response, replaces the packet in error with the received copy. If no packet in error is found in the receive memory, the receive site transmits an acknowledgment to the transmit site. On receiving it, the transmit site repeats the transmission of the next sequence of outstanding serial numberless packets.

Packet transmission method without sending serial numbers

A mobile exchange office stores an identifier of a base station corresponding to an identifier of each mobile terminal. The base station stores identifiers of base stations corresponding to an identifier of a mobile terminal except for own identifiers. Receiving a call signal for a mobile terminal, the mobile exchange office searches an identifier of a base station corresponding to the mobile terminal based on this call signal and sends a call signal to a base station in accordance with this searched identifier. The base station determines a sender of the call signal. If the sender is a mobile exchange office, the base station transfers the call signal to another base station corresponding to a stored identifier and calls the mobile terminal in own radio zone. If the sender is a base station, it calls the mobile terminal in own radio zone.

Method for calling a mobile terminal in a mobile communication system

A control signaling network comprises broadcast layers (80-111) in a tree-like arrangement and, if necessary, means (10-33) provided between the broadcast layers to check whether the broadcast data is to be passed or discarded. A mobile switching center (1-8) has a location registration data table (40-44) for storing a location registration area identification of a mobile apparatus and a broadcast data table (50-52) for storing identifications of the broadcasts layers governed by a different mobile switching center required to broadcast the broadcast data for mobile station call or identifications of broadcast layers governed by the different mobile switching centers.

Control signaling network, radio base station and mobile switching center

A packet communication system is capable of rapidly carrying out receipt confirmation for transmission of a downward packet signal. When a radio base station (100) wishes to obtain from a terminal (101) response information indicating that the terminal has received a downward packet signal, the radio base station temporarily inhibits a terminal (102) from transmitting an upward packet signal so as to enable the terminal to transmit as an upward packet signal a packet signal containing the response information.

Packet communication system capable of rapidly confirming receipt of

In a radio communications system wherein a common channel is accessed from multiple terminals, any of the terminals is allowed to transmit a packet through the common channel to a base station on a random access mode when the packet received at the base station has a low error rate, and a specified one of the terminals is allowed to transmit a packet on a controlled access mode when the packet received at the base station has a high error rate.

Dual mode multiple access method for common radio channel

A mobile switching center of this invention includes a public network interface, a communication signal processing unit for performing code translation, a packet switching unit for performing switching of a packet signal between the communication signal processing unit and a radio base station in accordance with the destination of the packet signal, and a packet signal selecting apparatus. The packet signal selecting apparatus includes one input terminal, a plurality of signal storage sections for respectively storing a plurality of packet signals input through the input terminal, a switching means for distributing a plurality of continuously input packet signals to the plurality of signal storage sections and causing them to respectively store the signals, and a discrimination unit for comparing some or all of the packet signals stored in all the signal storage sections with each other to select one packet signal, and outputting the selected packet signal.

Packet signal selecting apparatus and mobile switching center including

A mobile communication system and its multiple connection method enabling to perform concise and high quality multiplex communication, in which a mobile exchange station stores identifiers of a plurality of radio base stations and transmits a communication signal directed to a mobile station to all the radio base stations. The mobile exchange station stores the identifier of the radio base station which started the communication with the mobile station within the plurality of radio base stations. When the radio base station has opened a radio line with the mobile station, the radio base station which received the communication signal transmits the communication signal to a radio zone, and when the radio base station does not open the radio line with the mobile station, the radio base station disuses the received communication signal. When receiving a communication channel handover request, the radio base station which received the communication signal directed to the mobile station from the mobile exchange station executes a handover processing directly, and when not having received the communication signal, the radio base station requests the mobile exchange station to transmit the communication signal to carry out a multiple connection processing.

Mobile communication system and its multiple connection method enabling

The handover method disclosed relates to a mobile communication system in which, based on the number of handovers in mobile units, the size of the radio zone to be assigned to a mobile unit is selected. The mobile switching center measures the number of handovers in each of the mobile units engaging in communication and, during the handover in the mobile unit, the handover target radio zone is assigned based on the measured value of the number of handovers. The target handover of mobile units is determined by the target determination controller based the number of handovers memorized in the handover number recorder. The assignment of the appropriate size radio zone prevents an excess load on the mobile switching center and the capacity to accommodate subscribers in the mobile communication system is enhanced.

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Tokyo, Japan

Masanori Taketsugu