Transmission controller, wireless base station, and method of controlling transmission rate

A wireless base station which controls a plurality of downlink transmission rates corresponding to a plurality of mobile stations based on a plurality of downlink transmission qualities corresponding to the mobile stations, comprising:

• a transmission-quality obtaining unit configured to obtain said downlink transmission qualities of said mobile stations;
• a mobile-station selecting unit configured to select out of said mobile stations one or more which cause to change corresponding one or more of the downlink transmission rates in accordance with said downlink transmission qualities obtained at said transmission-quality obtaining unit;
• and
• a transmission-rate changing unit which causes to change said one or more of the downlink transmission rates corresponding to said one or more of the mobile stations selected at said mobile-station selecting unit.

A method of controlling transmission rate which controls a plurality of downlink transmission rates corresponding to a plurality of communications terminals based on a plurality of downlink transmission qualities corresponding to the communications terminals, comprising the steps of:

• obtaining said downlink transmission qualities of said communications terminals;
• comparing with a predetermined quality value corresponding values of said downlink transmission qualities obtained;
• selecting, when at least one of said downlink transmission qualities is determined to fall below a predetermined quality, as one or more of the communications terminals which cause to change corresponding one or more of the downlink transmission rates, at least one communications terminal out of said communications terminals with corresponding downlink transmission quality falling below said predetermined quality;
• and
• changing said downlink transmission rate of said at least one communications terminal selected.