Ntt Docomo, Inc.

Yukiko Takagi

Akihiro Fujiwara

Akihito Hanaki

Takahiro Hayashi

Yoshikazu Goto

Junichiro Kawamoto

A receiving apparatus () provided with: a management unit () configured to manage a target error rate Pt in a target number of retransmission Nt; a measurement unit () configured to measure the initial transmission rate TPUTof the data at a transmitting apparatus (); and a calculation unit () configured to calculate, with respect to an error rate P(n) in a number of retransmission n, the reception rate TPU of data at a receiving apparatus () by a Equation (2A). 

Receiving apparatus

In a radio communication system in which a radio terminaltransmits, to a base station, uplink user data via an enhanced dedicated physical data channel, the base stationincludes a base station side transmitter unit (scheduling unit) configured to transmit, to the radio terminal, transmission rate decrease data for instructing a decrease of the transmission rate assigned to the radio terminal, when the uplink user data is not transmitted from the radio terminalto the base stationby using the transmission rate assigned to the radio terminal

Radio communication system, radio communication method and base station

A base station according to the present invention includes: a detecting unit configured to detect a discard of the uplink user data received from a radio terminal; and a scheduling unit configured to transmit an AG or an RG instructing a decrease of an SG assigned to the radio terminal, when the discard of the uplink user data is detected by the detecting unit.

A radio base station according to the present invention includes: a determiner determining a transfer rate of data transferred from the radio network controller to the radio base station, based on a predetermined bandwidth of a wired transmission path, a bandwidth of the wired transmission path not being used, and a bandwidth of the wired transmission path being used by the mobile station; and a notifier notifying the radio network controller of the determined transfer rate.

Radio base station and mobile communication method

A radio terminaltransmits, to a base station, uplink scheduling information including at least a transmission power ratio (UPH) indicating a ratio of a maximum transmission power to a transmission power of a DPCCH. The base stationtransmits, to the radio terminal, transmission rate decrease data that instructs a decrease of a transmission rate assigned to the radio terminal, when the transmission power ratio included in the uplink scheduling information is below a first threshold.

Radio communication system, radio communication method, base station and radio terminal

A base station includes: a determination unit that determines whether or not a total of an initial transmission rate and assigned transmission rates exceeds a maximum receiving transmission rate when the base station receives a communication start request from a radio terminal; a selecting unit that selects a decrease target terminal when the total of the initial transmission rate and the assigned transmission rates exceeds the maximum receiving transmission rate; and a transmitting unit that transmits transmission rate decrease data to the decrease target terminal, and the base station causes the total of the initial transmission rate and the assigned transmission rates to be equal to or less than the maximum receiving transmission rate by transmitting the transmission rate decrease data.

Radio communication system, radio communication method, and base station for controlling a transmission rate of uplink user data

A transmission rate control method according to the present invention includes: determining, at the radio base station NodeB, a maximum granted value that can be notified to the mobile station UE, in accordance with a throughput at which the uplink user data transmitted from the mobile station UE to the radio base station NodeB is successfully received at a point of time; calculating, at the radio base station NodeB, as an allowable value to be notified to the mobile station UE, a granted value not more than the maximum granted value; notifying, from the radio base station NodeB to the mobile station UE, the granted value calculated at the radio base station NodeB, by using a transmission rate control channel; and transmitting, from the mobile station UE, the uplink user data, at the transmission rate corresponding to the granted value notified from the radio base station NodeB.

Transmission rate control method and radio base station

A base stationincludes: a specifying unitconfigured to specify a decrease target TTI that indicates the TTI in which a sum of already assigned transmission rates is larger than an allowable receiving transmission rate; a selecting unitconfigured to select, as a decrease target radio terminal, the radio terminal to which the TTI in the decrease TTI is assigned; and a scheduling unitconfigured to transmit, to the decrease target radio terminal, transmission rate decrease data that is the transmission rate control data (AG or RG) for instructing a decrease of the transmission rate.

A transmission rate control method according to the present invention includes: selecting, at the radio base station NodeB, increase-allowed mobile stations whose uplink user data transmission rate can be increased at a predetermined TTI; equally dividing, at the radio base station NodeB, an available radio resource at the predetermined TTI, based on the number of increase-allowed mobile stations or the number of E-AGCHs that can be transmitted in the cell; and adding, at the radio base station NodeB, the radio resource equally divided by a radio resource allocating unitA, to each radio resources allocated to each mobile stations to which a transmission rate control channel (E-AGCH) can be transmitted and is one of the increase-allowed mobile stations.

Transmission rate control method, mobile communication system and radio base station

A mobile communication system is configured as a mobile station in a first communication state shifts to a second communication state when at least one high speed uplink packet communication compliant radio link is established by the mobile station.

Mobile communication system, mobile communication method, and radio network controller capable of changing communication states

A mobile communication method includes: causing a cell under control of a radio base station to determine an initial granted value when an uplink user data transmission channel is set up between a mobile station and the cell under the control of the radio base station; causing a radio network controller to notify the mobile station of the initial granted value determined by the cell under the control of the radio base station; and causing the mobile station to transmit uplink user data via the uplink user data transmission channel at a transmission rate corresponding to the initial granted value after the uplink user data transmission channel is set up, and the cell under the control of the radio base station sets the initial granted value to be equal to the granted value used in transmitting only a single data unit on the uplink user data transmission channel.

Mobile communication method, mobile communication system, and radio base station

A transmission rate control method including: notifying, from the mobile station UE to the radio base station NodeB, a data amount in a transmission buffer of the mobile station UE; determining, at the radio base station NodeB, a maximum allowable value that can be notified to the mobile station UE, in accordance with the data amount in the transmission buffer; calculating, at the radio base station NodeB, as a granted value to be notified to the mobile station UE, a value that does not exceed the maximum allowable value, notifying, from the radio base station Node B to the mobile station UE, the granted value calculated at the radio base station UE, by using a transmission rate control channel; and transmitting, at the mobile station UE, the uplink user data, at a transmission rate corresponding to the granted value notified from the radio base station NodeB.

A mobile communication method includes: (A) assigning, at a radio network controller, a channelization code and a transmission timing for the mobile station on the basis of a status of use of a channelization code and a transmission timing in a sector other than a specific sector when the mobile station sets a radio link with the radio base station in the specific sector; and (B) notifying, from the radio base station, the mobile station of the transmission power control information via the transmission power control channel using the channelization code and the transmission timing assigned at the radio network controller.

Mobile communication method, mobile communication system and radio network controller

The radio base station includes: a step of making a comparison between transmission format identification information received from the mobile station and transmission format identification information based on a data amount calculated in a step of calculating the data amount of uplink user data; and a step of retransmitting a calculated scheduling grant if the radio base station determines, based on the comparison result in the step of the comparison, that a data amount indicated by the transmission format identification information received from the mobile station is larger than the data amount calculated in the aforementioned step.

Mobile communication method, mobile communication system and radio base station

A mobile communication method according to the present invention includes: controlling, at the radio base station NodeB, the transmission power in the DPCCH by use of an inner loop transmission power control based on a target SIR; transmitting, at the mobile station UE, the uplink packet, at the transmission power in the E-DPDCH, the transmission power being determined based on the SG and the transmission power in the DPCCH; and determining, at the radio base station NodeB, the target SIR, by use of an outer loop transmission power control based on a HARQ transmission number and a reception result of an uplink packet transmission of the HARQ transmission number, the HARQ transmission number indicating what number transmission in the HARQ retransmission control is the uplink packet transmission.

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Yokosuka, Japan

Yukiko Takagi