Date of Award


Degree Type


Degree Name

Doctor of Philosophy in Electrical Engineering


Electrical, Computer, and Biomedical Engineering

First Advisor

Tao Wei


Optical time-domain reflectometers (OTDRs) are the most widely used tool to diagnose an optical fiber in a telecommunication network; however, current OTDR systems cannot be efficiently utilized in industry due to their modularized design and bandwidth limitations. Furthermore, even when used as a standalone diagnostic technique, they lack the ability to have high spatial resolution and dynamic range concurrently which is essential for troubleshooting fiber optic cables in both shortreach networks, such as those in a datacenter, as well as long-haul networks, such as fiber-to-the-home. This study tackles these limitations by taking a statistical approach to replace the required high-end analog-to-digital converter in the traditional OTDRs receiver with a single comparator, or digital input/output interface, to substantially decrease both the form-factor and cost while inherently increasing the bandwidth and re-configurability of the system. Additionally, the proposed design requires little to no hardware modification to existing optical transceivers. The design can simply utilize the components already in existence in these transceivers to realize a high-end built-in OTDR. Furthermore, the increased performance enables the intrinsic “fingerprint” of the optical fiber, namely, Rayleigh backscattering, to be extracted for authentication and sensing applications with major advantages over current state-of-the-art systems.

Available for download on Thursday, January 05, 2023