Date of Award
3-2024
Document Type
Thesis
Degree Name
Master of Science in Cyber Operations
Department
Department of Electrical and Computer Engineering
First Advisor
Wayne C. Henry, PhD
Abstract
Since 1994, Bluetooth has been used as a Personal Area Network (PAN) to transfer data between devices within a short range. After thirty years of progressive improvement in functionality, security, range, and power efficiency, the Bluetooth Special Interest Group has released a new feature called Auracast, which allows users to tune into nearby public audio streams and receive the feed directly to their wireless headphones or hearing aids. Soon, venues such as convention centers, museums, public forums, and sporting arenas can implement Auracast to better suit their needs. In addition to these public benefits, the Department of Defense can take advantage of this technology to improve communication within military facilities and in the field. When multiple Auracast devices are broadcasting on the same 2.4 GHz frequency, signal collisions can result in malformed packets. These malformed packets decrease signal reliability, making the process of joining the audio stream take longer. The deliberate positioning of Auracast transmitters can minimize this interference and maximize signal longevity. This research evaluates the effects of two to six simultaneous broadcasts placed various distances apart on the number of malformed packets captured. These broadcasting devices are placed equidistant from a packet sniffing system positioned in the center. The purpose of this experiment is to determine the optimal separation distance for each quantity of broadcasters tested, which is the maximum spacing that still results in a signal strength of at least -62 dBm. It is assumed that the fewer broadcasters communicating at once and the closer they are positioned together, the fewer malformed packets that will result. The signal strength from each individual packet is leveraged to quantitatively achieve this goal. The results from the statistical analysis reveal the optimal separation distance for two or three simultaneous broadcast sources is approximately 45 ft, while four to six Auracast devices should be placed about 30 ft apart. These results enable administrators of multiple Auracast audio streams to maximize signal reliability for an unlimited-sized crowd. Overall, this research contributes to the characterization of this new Auracast technology and emphasizes its potential to improve a variety of applications.
AFIT Designator
AFIT-ENG-MS-24-M-026
DTIC Accession Number
AD1318962
Recommended Citation
Puseman, Lauren J., "Optimization of Bluetooth Auracast Broadcast Audio Transmissions via Signal Modeling" (2024). Theses and Dissertations. 7687.
https://scholar.afit.edu/etd/7687
Comments
A 12-month embargo was observed for posting this work on AFIT Scholar.
Distribution Statement A, Approved for Public Release. PA case number on file.