Patent ID: 7652978

Claim:
A transmitter of a communication system according to an orthogonal frequency division multiplexing (OFDM) method, comprising: a bit scrambler for performing bit scrambling of a transmission signal; a channel encoder for encoding the bit scrambled transmission signal; a bit inverter for performing bit inversion of predetermined bits of the encoded transmission signal by performing an exclusive AND operation on the encoded transmission signal with a mask bit column, wherein the mask bit column includes a number of bits equal to the number of bits to be inverted, and the number of bits to be inverted is determined based on a code block size and a channel environment and is fewer than the code block size; a symbol mapper for performing symbol mapping of the bit-inverted transmission signal; an inverse fast Fourier transform (IFFT) unit for performing inverse-fast-Fourier transform of the symbol mapped data into an OFDM symbol of a time domain; and a controller for estimating a peak-to-average power ratio (PAPR) of the inverse-fast-Fourier-transformed OFDM symbol in the time domain, comparing the estimated PAPR to a reference value, and, based on a result of the comparing, varying the mask bit column of the OFDM symbol to cause the bit inverter to invert the predetermined bits of the encoded transmission signal when the estimated PAPR is greater than the reference value, and outputting the OFDM symbol of the time domain when the estimated PAPR is not greater than the reference value.