Abstract: A method, an apparatus and a system for key derivation are disclosed. The method includes the following steps: a target base station) receives multiple keys derived by a source base station, where the keys correspond to cells under control of the target base station; the target base station selects a key corresponding to the target cell after knowing a target cell that a user equipment (UE) wants to access. An apparatus for key derivation and a communications system are also provided.

Abstract: The present invention relates to a method for adjusting forward transmission power control threshold in a mobile communication system, comprising the following steps of: setting in advance at the base station side an overload control threshold and an adjustment range of the power control threshold of sector forward transmission power; obtaining current total values of the forward transmission power of the sector; judging whether the sector forward transmission power exceeds said overload control threshold; judging whether the sector forward transmission power exceeds said adjustment range of the control threshold; dynamically adjusting the forward transmission power threshold, and so on.

Abstract: The present invention relates to a method for adjusting forward transmission power control threshold of a terminal in a mobile communication system, including the following steps of setting in advance at a base station side a forward pilot threshold and a lower bound, an upper bound of a forward transmission power control threshold as well as adjustment ranges of said lower bound and upper bound; obtaining the current forward pilot energy measured and reported by the terminal; judging whether the forward pilot energy exceeds said forward pilot threshold; and adjusting the forward transmission power control threshold of the terminal. In the invention, the forward pilot energy reported by the terminal is judged and adjusted through the pre-set parameters above, so as to dynamically adjust the forward transmission power control threshold of the terminal in the sector, reduce call drop rate, and promote the communication quality of a CDMA mobile communication system.

Abstract: A method and device for power overload control of the trunking group forward supplimental channel are disclosed, the method includes: reducing or increasing the higher limit of forward supplimental channel transmitting power of the sector trunking group users correspondingly based on whether the sector power is overload, and setting it as the target maximum transmitting power of the trunking group forward supplimental channels; dividing the trunking group users into groups based on the channel board, and determining the adjusting step size based on the ratio between the trunking group combining transmitting power of the users divided and the forward supplimental channel shared transmitting power of the sector trunking group, and the comparison between the forward supplimental channel shared transmitting power of the sector trunking group and the target maximum transmitting power of the trunking group forward supplimental channels, and adjusting the higher limit of the forward supplimental channel transmitting

Abstract: The present invention relates to a method for adjusting forward transmission power control threshold of a terminal in a mobile communication system, including the following steps of setting in advance at a base station side a forward pilot threshold and a lower bound, an upper bound of a forward transmission power control threshold as well as adjustment ranges of said lower bound and upper bound; obtaining the current forward pilot energy measured and reported by the terminal; judging whether the forward pilot energy exceeds said forward pilot threshold; and adjusting the forward transmission power control threshold of the terminal. In the invention, the forward pilot energy reported by the terminal is judged and adjusted through the pre-set parameters above, so as to dynamically adjust the forward transmission power control threshold of the terminal in the sector, reduce call drop rate, and promote the communication quality of a CDMA mobile communication system.

Abstract: The present invention relates to a method for adjusting forward transmission power control threshold in a mobile communication system, comprising the following steps of: setting in advance at the base station side an overload control threshold and an adjustment range of the power control threshold of sector forward transmission power; obtaining current total values of the forward transmission power of the sector; judging whether the sector forward transmission power exceeds said overload control threshold; judging whether the sector forward transmission power exceeds said adjustment range of the control threshold; dynamically adjusting the forward transmission power threshold, and so on.