Simultaneous Localization and Communication Method Using Short-Time and Narrow-Band Dual-Carrier Acoustic Signals

Abstract

This paper describes a novel acoustic localization and communication methods using multiple speakers. Acoustic signals for localization are modulated by differential phase shift keying to contain some information. Therefore, localization and communication can be conducted simultaneously. Regarding the design of acoustic signals, short-time and narrow-band acoustic signals are ideal to save time and frequency resources. However, if such signals are used with conventional methods, the interference of signals can occur and cause errors of localization and communication. Additionally, this error changes depending on the phase value that corresponds to the modulation for communication. To reduce this error, in our proposed method, a noninterference region in the received signal was constituted by using dual-carrier acoustic signals, and localization and demodulation were processed using this region. In the evaluation experiments, we estimate the azimuth of the microphone from two speakers and demodulate each of the symbols at 9 locations. Through simulation and real-environment experiments, it was confirmed that our proposed method can reduce the error caused by the interference. In real-environment experiments, the demodulation performance of our proposed method was similar to that of conventional methods. We discussed this similarity and revealed the cause.