Mitsubishi Electric Corporation

Mitsubishi Denki Kabushiki Kaisha

Mitsubishi Electronic Corporation

Yuji Kakehi

Mitsuru Mochizuki

Miho Maeda

Yasushi Iwane

Taisei Suemitsu

Masayuki Nakazawa

Taiga Saegusa

Hitoshi Kimura

A mobile communication system capable of easily notifying the interference-related information and avoiding interference in a situation in which a macro cell and local nodes are deployed to coexist. In the system, a macro cell (eNB) notifies, via user equipments (UEs) present in a coverage, HeNBs present in the coverage of the interference-related information related to the interference to a physical resource to be used, for example, a high interference indication (HII) and an overload indicator (OI).

Mobile communication system, mobile terminal and base station

A closed subscriber group (CSG) cell is a cell that allows use of subscribers. In order to receive the service by the CSG cell, a CSG-ID is required to be notified to a user equipment, which cannot be obtained in a situation outside the reach of radio waves from a non-CSG cell. In a mobile communication system including base stations respectively provided to a CSG cell and a non-CSG cell in which access is made to the CSG cell with the use of a CSG-ID issued in a case where use of the CSG cell is allowed, the base station provided in the CSG cell refers to the notified identification information of a user equipment and then transmits a tracking area update request from the user equipment to a core network, and the core network determines whether the user equipment is allowed to use the CSG cell and, in the case where the use is allowed, transmits a signal for allowing assignment of radio resources to the user equipment and the CSG-ID. The user equipment accesses the CSG cell with the use of the CSG-ID.

Mobile communication system

A mobile communication system capable of reducing energy consumption of a network node in a local area range. When judging that there is a shift trigger, a local eNB shifts from a normal operation to an energy saving operation. In the energy saving operation, the local eNB stops the operation of transmitting at least a part of downlink transmission signals to be transmitted to a user equipment (UE) and performs the operation of receiving an uplink transmission signal transmitted from the UE. When judging that it has received the uplink transmission signal (RACH) in the energy saving operation, the local eNB shifts to the normal operation.

Communication system, base station and mobile terminal

A mobile communication system includes a CSG cell which is accessible by a CSG member, a hybrid cell which is the CSG cell where a non-CSG member is also allowed access at the same time, and a mobile terminal which is subscribed as the CSG member and connected to the CSG cell or the hybrid cell as the CSG member. Even in a case in which a subscription time period has expired, the mobile communication system enables the mobile terminal to continue the connection. When the subscription time period for the CSG member expires, in case of the mobile terminal's connection to the CSG cell, the CSG cell initiates a handover, in case of the mobile terminal's connection to the hybrid cell, the hybrid cell changes treatment for the mobile terminal from treating the mobile terminal as the CSG member to treating the mobile terminal as the non-CSG member.

A mobile communication system capable of preventing interference in a communication system as well as reducing the load of a user equipment in a search operation. In the mobile communication system, radio communication is performed using a carrier having the same frequency in a direct link between a donor cell and a user equipment being served thereby and an access link between a relay node and a user equipment being served thereby. In a backhaul link between the donor cell and the relay node, radio communication is performed using a carrier having a different frequency from that of the carrier used in the direct link and the access link.

A mobile communication system hybridly allows, in a case where an access group consisting of one or more user equipments and one or more base stations is registered, the base station included in the access group to have access in a closed mode from the user equipment included in the same access group and access in an open mode from a user equipment that is not included in the same access group, wherein a communication area of the base station in the open mode is identical to a communication area of the base station in the closed mode. This eliminates a communication area in which the base station serving as an access destination differs between the user equipment in the closed mode and the user equipment in the open mode.

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Tokyo, Japan

Yuji Kakehi