A communication apparatus includes a Discrete Fourier Transform (DFT) transformer, a mapper, and a signal generator. The DFT transformer transforms a symbol in a time domain into a signal in a frequency domain with a DFT size that is a product of powers of a plurality of values, which are integer numbers greater than 1 and are different from each other. The mapper maps the signal in the frequency domain on a plurality of frequency bands, wherein a vector length corresponding to a size of each of the plurality of frequency bands is a product of two or more powers of prime numbers or a multiple of such product, and wherein the vector length is a number of subcarriers allocated to a corresponding one of the plurality of frequency bands. The signal generator generates a single carrier-frequency division multiple access (SC-FDMA) signal in the time domain from the mapped signal.