Audio Networking: The Forgotten Wireless Technology

Abstract

PERVASIVE computing 55Audio Networking:The Forgotten Wireless Technology M odern computing and communication devices offer a wide range of wireless communication protocols to transmit data, such as infrared, Bluetooth, and Wi-Fi. However, one technology has fallen off the radar in recent years, even though it's more ubiquitous with lower power requirements. Audio networking uses audible sounds as a lowbandwidth data channel and can enhance, for example, smart phone 1 usability. In that domain, audio networking offers both short-range communication with nearby devices as well as longer-range data transfer by introducing audio data packets into ongoing telephone conversations. Moreover, applying audio networking to smart phone applications doesn't change the fundamental devices people use to communicate. Instead, it can exploit the existing programmable interfaces that modern smart phones offer to augment modes of communication that people already know and use.In this article, we'll review various modulation schemes we've worked with previously, covering how to transfer data to nearby smart phones as well as usability and security issues. We'll consider audio networking as a mechanism for introducing data packets into ongoing mobile phone calls. We'll also discuss some real-world problems reported with telephone conferencing and apply audio-networking techniques to them in a case study application. 56 PERVASIVE computing www.computer.org/pervasive JULY-SEPTEMBER 2005 PERVASIVE computing 59 Telephone call Audio communication Other communication (such as Internet or phone) RFCOMM SCO Richard Dave RFCOMM SCO Internet Figure 3. Architecture of smart phone and PC/laptop integration via Bluetooth.

Chirp signal-based aerial acoustic communication for smart devices

“…4 The backend server basically manages a MySQL database that contains (i) API Key which is a unique ID of a specific app employing the chirp signal receiver, (ii) 16 bit ID received and demodulated by the receiver, and (iii) URL to be referred by the smart device. Fig.…”

An Approach to Secure Air-gap system from Intentional Radio Transmission

“…In [3], researchers introduced concept of "Audio Networking", to transmit data using inaudible data transmission. [4], discusses covert acoustical mesh networking.…”

Ambient noise analysis on sound for use in wireless digital transmission

“…Madhavapeddy, Scott, and Tse worked on audio networking which was a forgotten technology [3]. Theysuccessfully sent and received data and over sound using common computing platforms to do high frequency (ultrasonic) communication.…”

“…- (3) where f = frequency of the signal; asc = ASCII value of the text; s = frequency band shift factor; g = frequency gap…”