High data rate acoustic communications with nonideal channels

Radio-frequency (RF) electromagnetic waves provide valuable connectivity in wireless communication applications such as radio, television, and wireless internet. However, their attenuation in lossy media (e.g., water, biological tissues) and regulations due to safety and interference concerns limit their use in various applications. In such scenarios, acoustic waves can be an alternative method to transmit information wirelessly. Methods borrowed from RF communications often result in unsatisfactory performance in acoustic communication systems because wave propagation dynamics and channel characteristics are vastly different. In this thesis, we present alternative ways to overcome nonideal behaviors of acoustic communication media and devices to achieve higher performance than possible through standard communication techniques for ideal linear channels. In the first part of this thesis, we focus on ultrasonic communication through soft tissues for biomedical applications. We first present an ultrasonic through-body communication system capable of video streaming through biological tissues and animal subjects. We then examine the effects of acoustic nonlinearity on communication signals and develop a receiver that can compensate for the distortion introduced by the nonlinear through-tissue channel. In the second part of this thesis, we focus on through-air acoustic communication between personal computers using near-ultrasonic audio frequencies. We first develop a software-defined near-ultrasonic modem that uses the built-in laptop microphones and speakers to transmit short messages quickly, locally, and inaudibly. We then focus on the effect of audio system nonlinearities on the communication performance and present a neural-network-based receiver for a nonlinear near-ultrasonic communication system.

Name thesis:degree_name

Ph.D.

Level thesis:degree_level

Dissertation

Discipline thesis:degree_discipline

Electrical & Computer Engr

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2022

Author dc:creator

• Tabak, Gizem

Contributors dc:contributor

• Singer, Andrew C
• Hanumolu, Pavan Kumar
• Oelze, Michael L
• Smaragdis, Paris

• Wireless Communications
• Ultrasonic Communications
• Nonlinear Acoustics
• Channel Equalization
• Wireless Through-tissue Communications
• Wireless Through-air Communications

Statement dc:rights

• Copyright 2022 Gizem Tabak

Language dc:language

en, eng

Handle dc:identifier

https://hdl.handle.net/2142/117575

OAI record oai:identifier

https://www.ideals.illinois.edu/oai-pmh?verb=GetRecord&metadataPrefix=etdms&identifier=oai%3Awww.ideals.illinois.edu%3A2142%2F117575