A method of generating modulation signals is disclosed including generally three steps. A plurality of modulation signals are generated, each of which is to be transmitted from a different one of a plurality of antennas in an identical frequency band, wherein each modulation signal includes a pilot symbol sequence including a plurality of pilot symbols used for demodulation. Each of the pilot symbol sequences is inserted at the same temporal point in each modulation signal, wherein the pilot symbol sequences are orthogonal to each other with zero mutual correlation among the plurality of modulation signals, each pilot symbol having a non-zero amplitude, the quantity of the plurality of pilot symbols in each sequence being greater than the quantity of the plurality of modulation signals to be transmitted. The plurality of modulation signals each including different transmission data and one of the pilot symbol sequences are output to the antennas.