Method and base station for combined adjusting downlink AMC and MIMO mode

A base station for adjusting downlink Adaptive Modulation and Coding (AMC) and Multiple Input and Multiple Output (MIMO) modes comprising:

• a processor;
• and
• a storage device for storing processor executable instructions that when executed by the processor cause the processor to perform the steps in the following modules:
• an AMC module, configured to use a downlink Carrier to Interference plus Noise Ratio (CINR) fed back by a terminal to determine a current maximum available Downlink Interval Usage Code (DIUC), and send the maximum available downlink interval usage code (DIUC) to the joint adjustment module;
• a fast feedback module, configured to send a received MIMO mode fed back by the terminal to the joint adjustment module;
• and
• a joint adjustment module, configured to determine a current channel condition based on the received MIMO mode, and jointly adjust a current MIMO mode and a DIUC of the terminal within a maximum available DIUC range according to the current channel condition;
• wherein
• the joint adjustment module is configured to:
• when determining that the DIUC currently used by the terminal is greater than the maximum available DIUC, adjust the DIUC currently used by the terminal to the maximum available DIUC, and adjust the current MIMO mode of the terminal to a space time coding (STC) mode;
• when determining that the DIUC currently used by the terminal is less than or equals to the maximum available DIUC, the terminal is currently in the STC mode, and the MIMO mode fed back by the terminal is a spatial multiplexing (SM) mode, switch the MIMO mode currently used by the terminal to the SM mode, while remaining the currently used DIUC unchanged;
• when determine that the DIUC currently used by the terminal is less than the maximum available DIUC, the terminal is currently in the STC mode, and the MIMO mode fed back by the terminal is also the STC mode, adjust the DIUC currently used by the terminal to the maximum available DIUC, while remaining the current MIMO mode unchanged.