Ntt Mobile Communications Network, Inc.

Ntt Docomo, Inc.

Norihito Tokuhiro

Hidetoshi Yazaki

Kouji Chiba

Kazufumi Yunoki

Shigehide Sawayanagi

Masashi Kanauchi

Isao Hirakodama

An object of the present invention is to avoid congestion, by restricting only processing which causes the congestion without affecting processing which essentially should not be restricted. In a mobile communication system according to the present invention, an exchange MSC/SGSN includes: a congestion factor detector configured to detect a congestion occurrence factor in the switching exchange MSC/SGSN, and a restriction indication transmitter configured to transmit, a restriction indication, to a radio network controller, based on the detected congestion occurrence factor, the restriction indication instructing a processing type that should be restricted in the switching exchange MSC/SGSN congestion occurrence factor. The radio network controller RNC is provided with a broadcast information transmitter configured to transmit broadcast information including the received restriction indication to a mobile station UE.

Mobile communication system, mobile communication method, mobile station, and exchange

A control channel is searched for call waiting in a mobile station where the power supply for a receiving circuit is turned off during a break time of receiving level measurements, wherein in a first control channel selection mode, all the control channels are divided into a plurality of groups, the receiving levels of the control channels are measured group by group intermittently and sequentially. The intermittent measurement of these groups are repeated until a control channel having a receiving level equal to or greater than a first predetermined value is detected. When a receiving level equal to or greater than the first predetermined value is detected, the receiving levels of all the control channels are measured in a second control channel selection mode.

Method for searching a control channel in a mobile station

Method of activation of mobile station

Growing community of inventors

Yokohama, Japan

Norihito Tokuhiro