  Automating device pairing and credential exchange in consumer devices reduce
the time users spend with mundane tasks and improve the user experience.
Acoustic communication is gaining traction as a practical alternative to
Bluetooth or Wi-Fi because it can enable quick and localized information
transfer between consumer devices with built-in hardware. However, achieving
high data rates (>1 kbps) in such systems has been a challenge because the
systems and methods chosen for communication were not tailored to the
application. In this work, a high data rate, near-ultrasonic communication
(NUSC) system is proposed to transfer personal identification numbers (PINs) to
establish a connection between consumer laptops using built-in microphones and
speakers. The similarities between indoor near-ultrasonic and underwater
acoustic communication (UWAC) channels are identified, and appropriate UWAC
techniques are tailored to the NUSC system. The proposed system uses the
near-ultrasonic band at 18-20 kHz, and employs coherent modulation and
phase-coherent adaptive equalization. The capability of the proposed system is
explored in simulated and field experiments that span different device
orientations and distances. The experiments demonstrate data rates of 4 kbps
over distances of up to 5 meters, which is an order of magnitude higher than
the data rates reported with similar systems in the literature.
