Integrated circuit for inverse discrete fourier transforming a frequency domain signal to a time domain symbol sequence

An integrated circuit comprising:

• at least one input, which, in operation, inputs data;
• and
• circuitry coupled to the at least one input, which, in operation,
• receives signals mapped on a plurality of frequency bands in a frequency domain, each frequency band including a plurality of subcarriers, each frequency band being located at a position separate from position(s) of other(s) of the plurality of frequency bands, and a size of at least one of the plurality of frequency bands being a multiple of a product of two or more powers of prime numbers, the prime numbers being integer numbers that are greater than 1 and are different from each other, exponents for the prime numbers being a set of non-negative integers;
• combines the received signals into a combined signal;
• and
• transforms the combined signal in the frequency domain into a symbol sequence in a time domain with an inverse discrete Fourier transform (IDFT) having a size that is a product of powers of a plurality of values, the plurality of values being integer numbers that are greater than 1 and are different from each other, exponents for the plurality of values being a set of non-negative integers.