| 主权项 |
1. A radio base station of an adaptive array scheme for applying an antenna weight, comprising:
a plurality of antennas; and a transmission unit that includes an output communicatively coupled to the plurality of antennas and that transmits, to a serving radio terminal, information on a reference signal transmission frequency band available in a transmission of an uplink reference signal received from the serving radio terminal, the reference signal used by the radio base station to calculate the antenna weight for downlink transmission by the radio base station for the plurality of antennas, wherein the information transmitted by the transmission unit includes at least either one of information on a first reference signal transmission frequency band indicating a fixed frequency band, or information on a second reference signal transmission frequency band indicating a frequency band that switches in a predetermined cycle, the first reference signal transmission frequency band being wider than the second reference signal transmission frequency band, the transmission unit transmits the information on the first reference signal transmission frequency band, when the downlink data amount that must be transmitted to the serving radio terminal is equal to or more than a first threshold value, and the transmission unit transmits the information on the second reference signal transmission frequency band, when the downlink data amount that must be transmitted to the serving radio terminal is less than the first threshold value. |
