Ntt Docomo, Inc.

Kouji Makino

Yoshifumi Morihiro

Hiroto Tooyama

Anil Umesh

Narumi Umeda

Masafumi Usuda

Hidehiro Ando

Takuya Sato

Midori Mori

Shinsuke Sawamukai

Shinichi Sasaki

Masato Hiraki

A mobile communication system includes a first radio control device that manages a first cell, a second radio control device that manages a second cell, and a third radio control device. The second cell is set as a handover destination cell of the first cell. The third radio control device manages the second cell as a redundant configuration of the second radio control device. The third radio control device notifies the first radio control device of the third radio control device managing the second cell as the redundant configuration of the second radio control device. The first radio control device sets so that the third radio control device manages the second cell as the redundant configuration of the second radio control device.

Mobile communication system, and mobile communication method and radio control device used in mobile communication system

A second communication system starts transmission of direct data received from a core network apparatus without waiting to receive an end marker when the end marker indicating the last forwarding data forwarded from the first communication system is not received within an end marker waiting period.

Mobile communication system, network apparatus, and mobile communication method

A mobile communication system having a first communication system and a second communication system forwards forwarding data from the first communication system to the second communication system when switching from the first communication system to the second communication system is determined, the forwarding data being a data that the first communication system has already received from a core network device. A network device transmitting direct data to a mobile communication terminal via the second communication system is configured to count the number of switching times that the switching from the first communication system to the second communication system has been determined, for every user. The network device is configured to count the number of successful reception times that information identifying a user has been received via a forwarding path of the forwarding data, for every user. The network device is configured to judge whether the forwarding path of the forwarding data is normal or not on the basis of a ratio between the number of switching times and the number of successful reception times.

Mobile communication system, network device, and mobile communication method

A radio network controller activates a signal transmission suppression timer to suppress transmission of a congestion signal, when a new radio base station is added as a radio base station with which the radio terminal is to communicate, and suspends the transmission of the congestion signal to the radio base stations until the signal transmission suppression timer expires.

Radio communication system, radio network controller, radio base station and radio communication method

A radio network controller includes a block error detection unit configured to receive a data block from the base station and to detect a block error, and a target SIR calculation unit configured to calculate a target SIR based on the detected block error rate. The target calculation unit sets a first time section, which indicates a time section from a detection of the block error to the notification of the target SIR is to the base station when the block error is detected, shorter than a second time section, which indicates a time section from the detection of the block error to the notification of the target SIR to the base station when the block error is not detected.

Growing community of inventors

Yokosuka, Japan

Kouji Makino