Things that talk: Using sound for device-to-device and device-to-human communication

Nonlexical sound is explored as both a device-to-device and device-to-human communication medium. Considerations for device-to-device communication include robustness in various environments, potential interference, frequency limitations of conventional and piezoelectric devices, computational complexity, and strategies for ultrasonic and human-audible frequencies. Algorithms include modem protocols, information-hiding techniques, impulse coding, and dual-tone modulation. Considerations for device-to-human communication include the use of sounds that are unobtrusive in public settings and sounds that enable attention to be divided between the performance of complex tasks and real-time feedback.