Patent ID: 8526399

Claim:
A transmission control method for a radio base station which communicates with a radio mobile station by using code division multiplexing and adaptive modulation control, said transmission control method comprising: receiving a report from the radio mobile station with respect to reception quality which is measured for radio signals transmitted from the radio base station by the radio mobile station; setting a higher priority for an increase in a number of spread codes to be multiplexed than for a change increasing a level of a multi-level modulation of a modulation scheme; and selecting according to the priority set for a number of spread codes and a modulation scheme, and a provided constraint, a combination of a number of spread codes and a modulation scheme, transmitting information of the selected combination to the radio mobile station, and transmitting data to the radio mobile station in accordance with the selected combination, wherein when transmission using multiple spread codes and a first modulation scheme and transmission using a single spread code and a second modulation scheme that uses a larger number of signal points than the first modulation scheme are selectable, the first modulation scheme and the multiple spread codes are preferentially applied to a control channel between the radio base station and the radio mobile station regardless of determination of the modulation scheme, for data transmission, determined.