Student(s): Owen Funk, Colin Gregg, Eli Juvan
Project: Acoustic Underwater Direction Finding
Advisor(s): Rosa Zheng
Abstract
Underwater direction finding is a critical and challenging operation for Autonomous Underwater Vehicles (AUVs). In situations where visual navigation methods are unavailable, acoustic pingers are commonly used to provide crucial beacons for AUVs by marking points of interest. In the RoboSub competitions, two acoustic pingers are used to mark two out of five tasks for the AUV to complete in 20 minutes. The Lehigh Underwater Robotics team needs a pinger and a direction-finding receiver.
Our project seeks to create an integrated Direction of Arrival (DoA) detection system, including the transmitter and multi-channel receiver. The transmitter consists of a Tiva Microcontroller (MCU), a Class-D power amplifier (PA), and an acoustic projector. The pulsed single tones of 25 kHz to 40 kHz signals are selected from DIP switches read by the Tiva MCU, and Pulse Width Modulation (PWM) signals are generated to drive the Class-D PA and projector. The direction finding receiver utilizes four hydrophones, 4-channel low-noise Voltage-Controlled Amplifiers (VCA), and an STM32 MCU to perform the MUltiple Signal Classification (MUSIC) algorithm for DoA estimation.
The system has been integrated and tested extensively in an anechoic water tank and a swimming pool. The experimental data show that the transmitter worked as intended and is comparable to obsoleted commercial products. The development of the DoA receiver has encountered many technical challenges and achieved the major functionalities. More testing and debugging are required to improve quantitative results, such as DoA estimation accuracy, hydrophone array calibration, run-time robustness, firmware optimization, and power-on automation.
About Owen Funk
Major: Electrical and Computer Engineering
Owen Funk is a fourth year Computer Engineering student from Telford, Pennsylvania. Throughout their time at Lehigh University, they have been a member of the Lehigh Underwater Robotics club and participated in the 2023 Robosub Competition, and in 2025 performed research on the ADC characteristics of the Xilinx XADC module with Dr. Rosa Zheng. In 2025 he received the ECE Karakash Award, and the Horger Visual and Performing Arts Award. He is currently working on developing firmware for an underwater direction finding system for his senior design project. After graduation, he plans to pursue a career in industry as a Computer Engineer. In addition to engineering, he has played the clarinet in the Lehigh Philharmonic Orchestra, Wind Ensemble, and Marching 97.
About Colin Gregg
Major: Electrical and Computer Engineering/Finance
Colin Gregg is a fourth year Electrical Engineering and Finance student from Milford, New Hampshire. During his time at Lehigh University, he is a part of the Integrated Business and Engineering Honors program, was an analyst with the Investment Management Group, and played Club Rugby for two years. He spent one summer with the Lehigh Startup Academy working with a startup to help measure electric vehicle battery health for cars that had recently been in an accident, and another developing an inventory management system for spare parts for a glass manufacturer. Currently, his interests are in hardware and mixed-signal circuit design for high precision measurement devices, and making audio electronics circuits. Beyond school, Colin enjoys self-learning, weightlifting, and drawing.
About Eli Juvan
Major: Electrical and Computer Engineering
Eli Juvan is a graduating senior in Electrical Engineering at Lehigh University with an appreciation for first principles reasoning and leveraging the breadth of ECE. He has worked under his project advisor, Dr. Rosa Zheng, as both a summer intern and as a TA for Lehigh’s Introduction to Engineering ECE Lab section. Eli is from Middlebury, Connecticut, and is the proud owner of a chocolate Dutch rabbit.