Ntt Docomo, Inc.

Masayuki Motegi

Hideaki Takahashi

Takehiro Nakamura

Yasuhiro Kato

Yoshitsugu Shimazu

Narumi Umeda

Hidetoshi Kayama

Wuri Andarmawanti Hapsari

Minami Ishii

Mikio Iwamura

Anil Umesh

Seizo Onoe

Daisuke Koizumi

Hideki Tobe

Sadayuki Abeta

Atsushi Harada

Naoki Nakaminami

Tadashi Uchiyama

Takeshi Yamashita

Masahiro Yamato

In a mobile communication system according to the present invention, an AP/ULP layer of a transmission-side node (A) is configured to acquire, from a SCTP layer of the transmission-side node (A), a 'rwnd' for each connection of the SCTP layer, a 'cwnd' for each physical path, and a third data amount indicating an amount of data transmitted within a unit time by the transmission-side node (A) for each stream; and when an urgency flag is included in data subject to transmission, the AP/ULP layer of the transmission-side node (A) is configured to determine a stream and a physical path through which the data subject to transmission should be transmitted, based on the &#x201c;rwnd&#x201d;, the &#x201c;cwnd&#x201d;, and the third data amount, and to notify, to the SCTP layer, the determination.

Mobile communication system and transmission-side node

A handover method according to the present invention includes the steps of: forwarding, at a handover-source radio base station (eNB), user data (A) for a mobile station (UE) to a handover-target radio base station (eNB) when it is determined that a handover processing is to be performed, the user data (A) being stored in the handover-source radio base station (eNB); activating, at the handover-target radio base station, a predetermined timer when transmitting a path switch request to a path control apparatus, and storing second user data for the mobile station received from the path control apparatus until the predetermined timer expires; and forwarding, at the handover-target radio base station, the stored second user data to the mobile station after the predetermined timer expires.

Handover method and radio base station

A mobile communication method according to the present invention includes: the steps of: (A) transferring, from a first radio base station (S-eNB) to an upper level node (S-GW), consecutive uplink data received from a mobile station (UE) with their sequence numbers being consecutive, by use of a resource allocated by the upper level node (S-GW), when the first radio base station (S-eNB) determines that the mobile station (UE) is to perform a handover; (B) transmitting, from the first radio base station (S-eNB) to the upper level node (S-GW) transfer completion notification data after the transfer of the consecutive uplink data to the upper level node (S-GW) is completed; and (C) releasing, at the upper level node (S-GW), the resource when receiving the transfer completion notification data.

Mobile communication method and radio base station

Embodiments of the present invention make it possible to reduce loss and delay of downlink user data transmitted at regular time intervals in a mobile communication system employing a hard handover method, and make it possible to easily perform high-quality handover solely by a handover-starting base station. A base station for transmitting downlink user data at regular time intervals to a mobile station is disclosed. The base station is configured to transmit a handover-command signal immediately after transmitting the downlink user data to the mobile station.

Base station and handover control method

A plug-and-play radio base station autonomously establishes X2 logical interfaces and S1 logical interfaces with existing base stations and upper nodes. A new radio base station which is installed in a network advertises an IP address of the new radio base station over a transport network. An existing radio base station or an upper node which receives the IP address detects the number of hops from the new radio base station to the existing radio base station or the upper node. An initial logical interface with the new radio base station is established when the detected number of hops is below a predetermined threshold.

Logical interface establishing method, radio base station, and communication management apparatus

A radio base station (T-eNB) is configured to set up a data forwarding tunnel for forwarding user plane data to the radio base station (T-eNB) only for an access bearer for which the user plane data to be forwarded exists, when receiving a notification from a handover-source radio base station (S-eNB) as to whether or not the user plane data to be forwarded exists for each access bearer. The notification being made by using a handover request message for the mobile station (UE), and the access bearer being set up between the radio base station (T-eNB) and a upper level node (SGW).

A shared transmission/reception apparatus (OF-TRX) includes: a transmission/reception processor section (TRX-B) for a mobile communication system B configured to perform frequency conversion processing on a transmission baseband signal for the mobile communication system B outputted from a signal converter section (E/O), and to output a transmission radio frequency signal for the mobile communication system B; a power level adjuster section (VA) configured to adjust a power level of a transmission radio frequency signal for a mobile communication system A inputted from a transmission/reception processor section (TRX-A) for the mobile communication system A; a combiner section (COM) configured to generate a transmission radio frequency signal by combining the transmission radio frequency signal for the mobile communication system A outputted from the power level adjuster section (VA) and the transmission radio frequency signal for the mobile communication system B outputted from the transmission/reception processor section (TRX-B) for the mobile communication system B; and a common amplifier section (PA) configured to amplify a power level of the transmission radio frequency signal outputted from the combiner section (COM) at a predetermined amplification rate, and to output the resultant signal.

Radio base station apparatus

A trace reporting method, in which a user terminal reports to a tracking area management apparatus a trace along which the user terminal has moved in a mobile communication system, includes the steps of storing, by the user terminal, identifiers of base stations where the user terminal has performed cell selection in an identifier storage unit; and reporting, by the user terminal, to the tracking area management apparatus the identifiers stored in the identifier storage unit upon communicating with a base station. The tracking area management apparatus may compare the reported identifiers with a prestored pattern and assign a tracking area to the user terminal based on the comparison.

Trace reporting method, tracking area assigning method, user terminal, base station, and tracking area management apparatus

A shared AMP includes: a transmission/reception processor section (TRX-B) for a second mobile communication system configured to perform frequency conversion processing on an inputted transmission baseband signal for a mobile communication system B, and to output a transmission radio frequency signal for the second mobile communication system; a power level adjuster section (VA) configured to adjust a power level of an inputted transmission radio frequency signal for a first mobile communication system; a combiner section (COM) configured to generate a transmission radio frequency signal, by combining the transmission radio frequency signal for the first mobile communication system outputted from the power level adjuster section (VA) and the transmission radio frequency signal for the second mobile communication system outputted from the transmission/reception processor section (TRX-B) for the second mobile communication system; and a common amplifier section (PA) configured to amplify a power level of the transmission radio frequency signal outputted from the combiner section (COM) at a predetermined amplification rate, and to output the resultant signal.

An upper node and a handover source radio base station store setup information on an access bearer having been set up between the upper node and the handover source radio base station. A mobile communication method according to the present invention includes the steps of: (A) informing, from the handover source radio base station to a handover target radio base station, the access bearer setup information; (B) storing, at the handover target radio base station, the access bearer setup information informed of by the handover target radio base station; and (C) setting up, at the upper node, an access bearer between the upper node and the handover target radio base station by using the stored access bearer setup information without performing reallocation processing of new access bearer setup information, the access bearer being set up in response to a path switching request from the handover target radio base station.

Mobile communication method, radio base station and upper node

A base station according to the present invention includes: a data storage unitconfigured to temporarily store user data, when the base station transmits and receives the user data to and from a mobile station; an identifier adding unitconfigured to add, to the user data stored in the data storage unit, a transfer identifier which indicates that the user data is transferred to an other base station by a handover, when the mobile station performs the handover from the base station to the other base station; and a data transfer unitconfigured to transfer, to the other base station through a transfer apparatus, the user data to which the transfer identifier is added.

Base station and data transfer method for transferring data when a mobile station performs a handover

The logical channels are made to include a logical channel for control and a logical channel for data transmission, the radio physical channel are made to be commonly used for a plurality of logical channels, and one logical channel is made to have a correspondence relationship with one radio physical channel, and the channel assignment apparatus includes: traffic monitoring detection means that detects occurrence of traffic of the logical channels; and logical channel assignment means that, according to occurrence of the traffic of the logical channels, sequentially assigns required resources on the radio physical channel to the logical channels, so that the object is achieved.

Channel assignment apparatus and channel assignment method

A radio physical channel is available to multiple logical channels commonly, and multiple radio physical control channels are provided concomitantly with the radio physical channel and include a commonly usable common control channel. A channel transmission apparatus includes a logical channel type determination unit determining a type of a logical channel, and a channel transmission unit transmitting an identifier of the UE in the radio physical control channel depending on the type of the logical channel. A scheme of identifying the UE in the radio physical control channel is modified depending on the type of the logical channel.

Apparatus and method for channel transmission

A downlink packet scheduling method is disclosed for a shared channel or a common channel in a mobile communication system between a base station and a mobile station, the method including a step in which the base station determines whether there is a waiting packet to be transmitted to the mobile station other than a current transmission packet; a step in which when it is determined that there is no waiting packet to be transmitted, the base station sets a stop period 't' in which packet transmission is temporarily stopped after the current packet transmission; a step in which the base station transmits information indicating the stop period 't' through a schedule information channel transmitting schedule information of downlink packets; and a step in which the base station stops the packet transmission to the mobile station during the stop period &#x201c;t&#x201d; after the current packet transmission.

Packet scheduling method, base station, and mobile station in mobile communication system

A radio base station transmits user common data provided from a user common data control apparatus connected to a communication network to a plurality of mobile stations by radio. The radio base station includes a frame loss detection unit configured to detect loss of user common data that occurs on a transmission route between the radio base station and the user common data control apparatus, and a timing adjustment unit configured to change transmission timing of the user common data for the mobile station according to the loss of the user common data.

Growing community of inventors

Yokohama, Japan

Masayuki Motegi