Ultrasonic data transmission through a rebar-reinforced concrete acoustic channel

Amodeo, Zachary
Thumbnail Image
Other Contributors
Saulnier, Gary J.
Schoch, Paul M.
Sawyer, Shayla Maya Louise
Issue Date
Electrical engineering
Terms of Use
This electronic version is a licensed copy owned by Rensselaer Polytechnic Institute, Troy, NY. Copyright of original work retained by author.
Full Citation
For cases in which digital data must be transferred through a solid object while maintaining its structural integrity, commonplace methods using radio waves or wires running through the object may be impractical. Materials like metals and concrete may block radio waves to an extent that achievable data rates are insufficient, and drilling into an object to pass wires through may result in leakage of fluids or compromised integrity of the material. In these cases, ultrasonic signals may be used to transfer data, requiring only that transducers be attached to the surface of the object. This document presents the results of using an orthogonal frequency-division multiplexed (OFDM) system using bit-loaded quadrature amplitude modulated (QAM) subcarriers to send data through a 70 cm thick rebar-reinforced concrete pillar using ultrasound. Data rates nearing 90 kbits/s are achieved with a bit error rate below 10⁻⁵, with approximately 2 mW of transmit power. Transient variability of the acoustic channel through the pillar is found to limit the bit error rate for a single bit-loading configuration, requiring the channel to be measured frequently or the bit-loading configuration to be adapted to the changing channel.
August 2017
School of Engineering
Dept. of Electrical, Computer, and Systems Engineering
Rensselaer Polytechnic Institute, Troy, NY
Rensselaer Theses and Dissertations Online Collection
Restricted to current Rensselaer faculty, staff and students. Access inquiries may be directed to the Rensselaer Libraries.