The transmitter of one embodiment of the present invention includes: a S/P section for converting original serial data to parallel data which will correspond to a plurality of subcarriers; and a second IFFT section for converting the parallel data from the frequency domain to the time domain. The transmitter includes, between the S/P section and the second IFFT section, a first IFFT section for modulating the plurality of subcarriers using elements of a matrix derived from an expression for Inverse Discrete Fourier Transform involving time domain signal levels and frequency domain signal levels. The configuration enables CI and PO-CI to be implemented on transmitters and receivers with a simple configuration.