A method and device for transmitting a preamble sequence is disclosed. A transmitter according to an embodiment may extract a first sequence for a non-coherent receiver and a second sequence for a coherent receiver, from ternary preamble sequences including elements −1, 0 and 1, and map the first sequence and the second sequence to a preamble including a plurality of bits to generate a third sequence that the non-coherent receiver and coherent receiver support.