Patent ID: 8078186

Claim:
A transmission rate control method in which a radio base station controls a transmission rate of uplink user data to be transmitted from a mobile station, comprising: notifying, from the mobile station to the radio base station, at a predetermined timing, a happy bit set to a first value, when the mobile station determines that a buffering time during which the uplink user data is buffered in a transmission buffer does not exceed a predetermined time, assuming that the mobile station continues to use a transmission rate corresponding to a current granted value notified by the radio base station; determining, at the radio base station, a maximum granted value that can be notified to the mobile station, in accordance with the happy bit notified from the mobile station; calculating, at the radio base station, as an allowable value to be notified to the mobile station, a granted value not more than the maximum granted value; notifying, from the radio base station to the mobile station, the granted value calculated at the radio base station, by using a transmission rate control channel; transmitting, from the mobile station, the uplink user data, at a transmission rate corresponding to the granted value notified from the radio base station; and wherein in the determining, the radio base station determines the maximum granted value that can be notified to the mobile station, in accordance with an average value of happy bit notified, within a predetermined time period, from the mobile station.