Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Shinsuke Uga

Mitsuru Mochizuki

Miho Maeda

Noriyuki Fukui

Yasushi Iwane

Tomomi Kasuya

Takao Wakabayashi

Takeshi Chikazawa

In a mobile communication system, an RRM measurement set is set as a collection of cells to become targets on which a UE performs a process of detecting whether or not radio communication is allowed. Among the cells in the RRM measurement set, a CoMP measurement set is set as a collection of cells to become candidates on which the UE performs a process of detecting whether or not coordinated communication (CoMP communication) is allowed. Among the cells of the CoMP measurement set, a CoMP active set is set as a collection of cells to become targets on which the UE performs the process of detecting whether or not CoMP communication is allowed.

Mobile communication system

Provided is a communication system that can be normally and efficiently operated in the case where existing carriers and new carrier types coexist. A base station device and a communication terminal device are configured to perform communication in cells of legacy carriers LC1 to LC3 being existing carriers. When the base station device starts operating new carrier types NCT1 and NCT2, the NCT1 and NCT2 are associated with legacy carriers belonging to the same frequency band. For example, the NCT2 is associated with the LC2 or the LC3 and is not associated with the LC1. The legacy carriers LC1 to LC3 associated with the NCT1 and the NCT2 notify the communication terminal device of the information on the NCT1 and NCT2. This allows the communication terminal device to communicate with the NCT1 and the NCT2.

Mobile communication system, source base station, target base station and user equipment

A communication system is provided that, if a large number of small cells are installed, is capable of configuring an operation suitable for small cells through simple operation and administration. If a small cell installed in Step STjudges in Step STthat a coverage macro cell, which includes the small cell in the coverage of the coverage macro cell, is present as a result of neighbor cell search in Step ST, notifies the coverage macro cell and another neighbor cell of its own capability in Steps STand. The coverage macro cell selects a configuration parameter suitable for the capability of the small cell in Step STand notifies the small cell in Step ST. The small cell recognizes an operation mode configured by the coverage macro cell from the configuration parameter notified from the coverage macro cell, and then, starts operating in the operation mode.

Mobile communication system, base station and user equipment

A UE in an idle state selects any of a group A, to which a cell of which coverage its own device is in, belongs and a group different from the group A, for example, a group B, and then measures cells belonging to the selected group for selecting a cell being a re-selection destination. A UE in a connected state selects any of the group B to which a cell connected with the UE belongs and a group different from the group B, for example, the group A, and measures cells belonging to the selected group for handover.

Communication system

A mobile communication system includes a movable user equipment device, a plurality of base station devices configured to perform radio communication with the user equipment device, and a relay device movably configured to relay radio communications between the user equipment device and the base station devices. In a handover process of switching a base station device to be connected with the relay device from a base station device being a moving source to a base station device being a moving destination along with moving of the relay device, the base station device being a moving source selects the base station device being a moving destination from base station devices other than a base station device that does not have a function supporting the relay device, and performs the handover process such that the relay device is connected to the selected base station device.

Provided is a communication system that can be normally and efficiently operated in the case where existing carriers and new carrier types coexist. A base station device and a communication terminal device are configured to perform communication in cells of legacy carriers LCto LCbeing existing carriers. When the base station device starts operating new carrier types NCTand NCT, the NCTand NCTare associated with legacy carriers belonging to the same frequency band. For example, the NCTis associated with the LCor the LCand is not associated with the LC. The legacy carriers LCto LCassociated with the NCTand the NCTnotify the communication terminal device of the information on the NCTand NCT. This allows the communication terminal device to communicate with the NCTand the NCT

Communication system using a predetermined first carrier in a first cell and a second carrier in a second cell

A mobile communication system includes a mobile station, a first base station and a second base station configured to perform radio communication with the mobile station, and a gateway station configured to perform communication with the first base station and the second base station or with the mobile station via the first base station and the second base station. One communication is performed between the mobile station and the gateway station by establishing a first communication connection between the gateway station and the first base station, a first radio communication connection between the first base station and the mobile station, and a second radio communication connection between the second base station and the mobile station. This enables a normal change of a cell during communication without any load on a network.

The present invention has an object to provide a mobile communication system capable of performing communication between a user equipment device connected to a relay device and a core network if the relay device moves. An RN () sets a TA of an eNB to be connected with the own device as a TA of the own device. For example, when the RN () moves along an arrow (), the TA of the RN () is changed from a first TA () to which a fourth eNB () belongs to a third TA () to which a tenth eNB () belongs. Upon change of the TA of the RN () as described above, a user equipment device (UE;) transmits a TA update request signal of the own device to a target second MME ().

In a communication system, an eNB and a UE transmit and receive a UE monitoring message for confirming the state of the UE in a predetermined UE monitoring period. For example, in UE monitoring periods, a UE monitoring procedure is performed, so that the UE transmits the UE monitoring message to the eNB. Upon receipt of the UE monitoring message, the eNB transmits delivery confirmation information to the UE. The UE monitoring period is set as, for example, a period shorter than a TAU period. This allows the UE monitoring process to confirm the state of the UE even if the TAU period is lengthened. The eNB may transmit the UE monitoring message to the UE.

A mobile communication system capable of performing communication between a user equipment device connected to a relay device and a core network if the relay device moves. A relay device sets a tracking area of a base station device to be connected with the own device as a tracking area of the own device. For example, when the relay device moves along an arrow, the tracking area of the relay device is changed from a first tracking area to which a fourth base station device belongs to a third tracking area to which a tenth base station device belongs. Upon change of the tracking area of the relay device as described above, a user equipment device transmits a tracking area update request signal of the own device to a target second mobility management entity.

Growing community of inventors

Tokyo, Japan

Shinsuke Uga