A peak level of amplitude of transmission signals in a multi-carrier communication
system or the like is to be effectively suppressed. A transmission data generating
unit generates digital transmission data from original data by an OFDM system.
A limiter of a peak suppressing unit limits a level of transmission data using
thresholds. A subtractor subtracts output data of the limiter from the transmission
data to generate differential data. A subtractor suppresses the peak level by subtracting
the differential data from transmission data whose timing is coordinated by delay
units. A transmitter unit converts the transmission data whose peak level is suppressed
into analog transmission signals, further converts their frequency, amplifies their
power, and transmits the frequency-converted and power-amplified signals to a radio
line via an antenna.
