A wireless LAN base station is provided with a noise signal scanning
antenna separately from a wireless signal reception antenna. An
attenuation circuit section attenuates the received signal from the noise
scanning antenna according to an attenuation factor from an attenuation
factor storage section. A distance setting storage section stores a
distance between the wireless signal reception antenna and the noise
scanning antenna. An attenuation factor storage section holds pieces of
data each of which indicates the relationship between the distance
between the antennas and an attenuation factor in the form of a table. An
attenuation circuit section employs the attenuation factor so as to
attenuate the received signal from the noise signal scanning antenna. A
subtraction circuit section subtracts an output signal of the attenuation
circuit section from the signal from the wireless signal reception
antenna, and reduces or eliminates a noise from the received signal from
the wireless signal reception antenna.