An encoding part (101) turbo-encodes data to be transmitted, outputs parity bit data and also outputs systematic bit data that must have a high quality. A modulating part (102) modulates the parity and systematic bit data. A subcarrier arranging part (103) rearranges the data to be transmitted so that the systematic bit data will be arranged on a subcarrier in the vicinity of the center frequency and the parity bit data will be arranged on subcarriers in the vicinity of both ends. An OFDM part (104) performs an orthogonal frequency division multiplexing of the data to be transmitted and arranges the parity and systematic bit data on the subcarriers. This can significantly improve the error rate characteristic of the data to be transmitted that must have a good quality, and also can prevent degradation of the quality of the data to be transmitted that must have a good quality. |