There is disclosed a radio communication system in which a constitution of
a base station and further a control station can be simplified. A radio
communication system according to the present invention converts a
received signal received by a plurality of antenna elements in a base
station to a signal of different frequency band, and then conflates the
converted signal in order to generate sub-carrier wave multiplex signal.
The signal is converted to an optical signal, and then the optical signal
is transmitted to a control station via an optical fiber. Or the control
station performs weighting to phase of the transmitted signal transmitted
from a plurality of antennas of a base station, and then performs
frequency conversion to different frequency band, and then conflates the
converted signal in order to generate the sub-carrier wave multiplex
signal. The signal is converted to an optical signal, and then an optical
signal is transmitted to the base station side via the optical fiber. The
control station and the base station divides the received sub-carrier
wave multiplex signal by each frequency band, and then the frequency of
the divided signals are converted to the same frequency band in order to
generate the transmitted/received signal of each antenna element. By such
a constitution, it is possible to reduce constituent of the optical
transmission components to the minimum and to simplify the constitution
of the base station. Furthermore, it is possible to maintain the relative
phase difference and the relative intensity of the transmitted/received
signal of each antenna element. Because of this, it is possible to
estimate an arrival direction of the received signal and to control
radiation beam pattern of the transmitted signal.