2022 年 11 巻 3 号 p. 141-147
This paper proposes 32kbps terrestrial acoustic communications (TRACs) and confirms their effectiveness by means of experimental results. TRACs suffer from low transmission information bit rate due to their narrow frequency band-width and severe double selectivity due to slow propagation speed of sound. The proposed TRACs have the following three features: 1) they employ single carrier block transmission with frequency domain equalization; 2) they compensate distortion of frequency response due to a speaker thanks to transmit precoding; 3) they improve tracking capability of mobile environments thanks to channel interpolation. Finally, experimental results confirm that the proposed TRACs can achieve 32kbps transmission information bit rate in hand-held conditions.
