Abstract: A wireless communication system includes an RNC and a BTS which communicates with the RNC. A congestion-notification transmitting unit of the BTS notifies the RNC of occurrence of congestion in a sector in which a mobile station is located. The RNC includes a congestion-notification receiving unit, a retransmission-ratio monitoring unit, and a transmission-rate control unit. The congestion-notification receiving unit detects the congestion occurrence by the notification from the BTS. The retransmission-ratio monitoring unit monitors a ratio of retransmission of a packet to the mobile station. The transmission-rate control unit performs control of changing a transmission rate of a packet to the mobile station according to the retransmission ratio when the congestion occurrence has been detected by the congestion-notification receiving unit.

Abstract: A wireless communication system includes an RNC and a BTS which communicates with the RNC. A congestion-notification transmitting unit of the BTS notifies the RNC of occurrence of congestion in a sector in which a mobile station is located. The RNC includes a congestion-notification receiving unit, a retransmission-ratio monitoring unit, and a transmission-rate control unit. The congestion-notification receiving unit detects the congestion occurrence by the notification from the BTS. The retransmission-ratio monitoring unit monitors a ratio of retransmission of a packet to the mobile station. The transmission-rate control unit performs control of changing a transmission rate of a packet to the mobile station according to the retransmission ratio when the congestion occurrence has been detected by the congestion-notification receiving unit.

Abstract: A mobile communication system has a mobile terminal, basestations, and a Radio Network Controller (RNC). In the case where drop of a frame occurs during data communication in Iub/Iur (between the basestations and the RNC), the RNC executes retransmission of an EDCH FP frame between the RNC and the basestations by transmitting a TN frame to the basestations to repair the drop of the frame without executing retransmission with the terminal device.

Abstract: A mobile communication system in which a mobile station copies data and transmits that copied data to a plurality of base stations, each base station sends that copied data to a serving radio network control device (S-RNC) directly or via a drift radio network control device (D-RNC), and the S-RNC selectively combines and outputs the received copied data; wherein a congestion monitoring unit monitors the congestion state of a line between the D-RNC and S-RNC, and when that line is congested, a D-RNC selectively combines the copied data that is inputted from the plurality of base stations and sends the result to that line, and when the line is not congested, the D-RNC sends the copied data that is inputted from the plurality of base stations to the line without performing selective combination.

Abstract: A communication method for use in a radio communications system in which a mobile station sends identical data to a plurality of radio base stations in a parallel fashion. The method determines which radio base stations should stop forwarding data to an intermediate network device managing them. The intermediate network device includes a monitor and a controller. The monitor checks continuity of sequence numbers affixed to data received from each radio base station, thereby detecting missing sequence numbers. Based on the statistics of missing sequence numbers, the controller selects which radio base station should be allowed to continue its data forwarding operation. The controller then requests the other, non-selected radio base stations to stop their data forwarding operation.

Abstract: The wireless base station notifies the missing to the transmitter upon detection of missing of a data segment received from the transmitter, and the transmitter controls the header compression state of the data segment addressed to the wireless terminal upon the reception of the notification of the missing.

Abstract: A packet transmitting apparatus 2 includes: a packet transmitting unit 20 which transmits a packet having a preassigned sequence number to a destination apparatus 3; a transmitted-packet indication information generating unit 21 which generates transmitted-packet indication information that indicates the packet transmitted by the packet transmitting unit 20; and a transmitted-packet indication information transmitting unit 23 which transmits the transmitted-packet indication information to the destination apparatus 3 separately from the packet.

Abstract: A buffer has a predetermined storage capacity, and accumulates data received from an external device. A transmitting unit reads data from the buffer and transmits the data to a mobile terminal. A transmission rate determining unit determines the transmission rate for transmitting data from the external device to its own device, based on the free space in the buffer. The window size notifying unit notifies the mobile terminal of a window size in accordance with the determined transmission rate.

Abstract: A mobile communication system has a mobile terminal, basestations, and a Radio Network Controller (RNC). In the case where drop of a frame occurs during data communication in Iub/Iur (between the basestations and the RNC), the RNC executes retransmission of an EDCH FP frame between the RNC and the basestations by transmitting a TN frame to the basestations to repair the drop of the frame without executing retransmission with the terminal device.

Abstract: A mobile communication system in which a mobile station copies data and transmits that copied data to a plurality of base stations, each base station sends that copied data to a serving radio network control device (S-RNC) directly or via a drift radio network control device (D-RNC), and the S-RNC selectively combines and outputs the received copied data; wherein a congestion monitoring unit monitors the congestion state of a line between the D-RNC and S-RNC, and when that line is congested, a D-RNC selectively combines the copied data that is inputted from the plurality of base stations and sends the result to that line, and when the line is not congested, the D-RNC sends the copied data that is inputted from the plurality of base stations to the line without performing selective combination.

Abstract: The wireless base station notifies the missing to the transmitter upon detection of missing of a data segment received from the transmitter, and the transmitter controls the header compression state of the data segment addressed to the wireless terminal upon the reception of the notification of the missing.

Abstract: A communication method for use in a radio communications system in which a mobile station sends identical data to a plurality of radio base stations in a parallel fashion. The method determines which radio base stations should stop forwarding data to an intermediate network device managing them. The intermediate network device includes a monitor and a controller. The monitor checks continuity of sequence numbers affixed to data received from each radio base station, thereby detecting missing sequence numbers. Based on the statistics of missing sequence numbers, the controller selects which radio base station should be allowed to continue its data forwarding operation. The controller then requests the other, non-selected radio base stations to stop their data forwarding operation.

Abstract: A transmission parameter control apparatus that improves transmission quality of real-time media in a transmission route that includes a wireless section in at least a part of the transmission route. The transmission parameter control apparatus is connected to a terminal via a network and is connected to a mobile terminal via a wireless link. The apparatus includes: an obtaining part for obtaining a quality parameter indicating transmission quality corresponding to the wireless link from signals of downlink and uplink transmission routes; and an adjustment part for adjusting a value of a transmission parameter determining a transmission scheme in the wireless link according to the quality parameter.

Abstract: An object of the present invention is to provide a transmission parameter control apparatus that can improve transmission quality of real-time media in a transmission route that includes a wireless section in at least a part of the transmission route. According to the present invention, a transmission parameter control apparatus 200 that is connected to a terminal 104 via a network 102 and that is connected to a mobile terminal 108 via a wireless link, is provided. The apparatus includes: an obtaining part 210 for obtaining a quality parameter indicating transmission quality corresponding to the wireless link from signals of downlink and uplink transmission routes; and an adjustment part 220 for adjusting a value of a transmission parameter determining a transmission scheme in the wireless link according to the quality parameter.