UNDERWATER ACOUSTIC COMMUNICATION DEVICE

PROBLEM TO BE SOLVED: To provide an underwater acoustic communication device which is capable of performing reliable communication and is low power consumption.SOLUTION: A transmission circuit provided transmits an acoustic signal in which m bits are frequency division multiplexed and that allocates two different carrier frequencies to each bit such that duplication does not occur across m bits. The transmission circuit is provided with: a bit state determination unit for determining the bit state of a bit for each bit; a carrier generation circuit for generating a carrier signal selecting one of two carrier frequencies according to the bit state of a bit for each bit; an addition circuit for adding a carrier signal for each bit generated by the carrier generation circuit over m bits; and a transmitter that comprises 2 m vibrators which have, as a resonance frequency, any of carrier frequencies assigned over m bits and transmits an acoustic signal. Inputs of 2 m vibrators are electrically connected with each other and the vibrators are driven according to output of the addition circuit.