Acoustic modem using OFDM and least-square channel estimation

Abstract

In this work, we present an acoustic modem system that transmits data using multicarrier modulation through the air interface. The choice for this type of modulation over single carrier modulation arises from the need for an efficient use of the limited bandwidth, the minimization of multipath effects as frequency fading. The system transmits data using sound waves resting on the output and input audio channel embedded in several devices. It employs the BPSK and QPSK digital modulations with an OFDM system, coherent detection and Least Sqares channel estimator from OFDM pilots.