Analysis and Design of Optical-Acoustic Techniques to Approach Fundamental Limits of Detection acros

Abstract

This program aims to develop a prototype of a Photoacoustic Airborne Sonar System (PASS) which can image underwater environments from an airborne platform. Previous work has demonstrated the proof-of-concept in a lab based setup. The operation of the system is illustrated in Figure 1. An intensity modulated laser is used to create underwater acoustic waves through the photoacoustic effect. The generated acoustic waves propagate under water, reflecting back from any targets that are present. The reflected acoustic waves pass through the air-water interface and are collected with highly sensitive capacitive micromachined ultrasonic transducers (CMUTs). Custom algorithms are used to reconstruct images of the underwater environment. Through this extended program, we aim to improve 1) imaging resolution, 2) achievable depths, and 3) imaging throughput achievable with PASS while focusing on system integration and miniaturization. To achieve these goals - on the transmitter side of the system - we will explore advanced laser excitation techniques and signal encoding schemes and - on the receiver side of the system - we will explore multi-element transducer arrays, develop surface mapping techniques (to enable imaging when the water has surface waves), and improve image reconstruction algorithms. Specific details about these tasks are outlined in later sections. This abstract is approved for public release

Document Details

Document Type
DoD Grant Award
Publication Date
Apr 01, 2022
Source ID
N000142212380

Entities

People

  • Amin Arbabian

Organizations

  • Office of Naval Research
  • Stanford University
  • United States Navy

Tags

Readers

  • Image Processing and Computer Vision.
  • Microwave Engineering.
  • Ocean-Atmosphere Mesoscale Modeling, Data Assimilation, and Flux Boundary Layers

Technology Areas

  • Directed Energy