Base station

A base station of a radio communication system including the base station and a mobile station that performs communication with the base station, the base station comprising:

• a first discovery signal transmitter that transmits a plurality of first discovery signals in respective different transmission directions from the base station through beam forming;
• and
• a second discovery signal transmitter that transmits, for each of one or more first transmission directions of the plurality of transmission directions corresponding to one or more first discovery signals of the plurality of first discovery signals reported from the mobile station, second discovery signals in a respective plurality of second transmission directions, the plurality of second transmission directions being within a predetermined range from the first transmission direction,
• wherein, when each second discovery signal of the plurality of second discovery signals is to be transmitted, the second discovery signal transmitter transmits the second discovery signal by multiplying, by a correction precoding vector, the second discovery signal to be transmitted, the correction precoding vector being for adding, to the first transmission direction, a difference in transmission angles between the first transmission direction that is within the predetermined range from the second discovery signal and a second transmission direction of the second discovery signal to be transmitted, and by performing beam forming for the second discovery signal, the correction precoding vector being multiplied to the second discovery signal, using a first weight matrix for performing beam forming in the first transmission direction that is within the predetermined range from the second discovery signal.