A wireless device includes: a plurality of antennas; a first correlation series generator configured to generate a first correlation series based on transmission data; a second correlation series generator configured to generate a second correlation series based on the first correlation series; a first modulator configured to modulate the transmission data to generate a first modulated signal; a second modulator configured to modulate the first correlation series to generate a second modulated signal; a third modulator configured to modulate the second correlation series to generate a third modulated signal; a signal combiner configured to combine the first to third modulated signals to generate first to third transmission signals; and a transmitter configured to output the first to third transmission signals respectively via first to third antennas among the plurality of antennas.