A Graduate Support Framework for the Study of Low Frequency Acoustic Communications
Abstract
Technical Problem - There is a need to develop basin-scale acoustic modems to enable bi-directional communications between underwate,r unattended sensors and systems. This problem is difficult due to the size, weight and power of systems using current approaches an,d due to the extremely challenging acoustic environment. A few Low Frequency acoustic systems exist that have tremendous underwater,range, including one operated by the University of Washington Applied Physics Laboratory (UW-APL). These unidirectional systems have, very large, low frequency projectors. Available modems operate at higher frequencies and are insufficient for long range communicat,ions. Solving this problem requires new transducers and innovative communications techniques to facilitate long-range bi-directional, communications across mixed o,ersity engineering graduate programs are shifting to a machine learning andcyber emphasis. ONR and the DoD need to get more young en,gineers with advanced degrees into critical fields like underwater acoustics, sonar imaging and acoustic communications.Objective -,The objective of this project is to bring the two problems together by creating advanced degree programs that center around solving,problems vital to DoD operations. This includes the simulation and design of transducers, algorithms and methods that stretch the re,the optimal design of multiple transducer types and signal processing techniques will be conducted by graduate students led by trans,ducer designers experienced in Sonar, Communications and Ultrasound applications. Transducer prototyping is supported by the UW-APL,in house transducer lab with skilled technicians running high precision ceramic saws, milling machines and test instruments. This al,lows students to understand the capabilities and limitations of simulation tools as well as the restrictions the manufacturing proce,ss places on design. In addition to the transducer, signal processing techniques will be employed to allow for reliable communicatio,ns over varying acoustic channels. As the acoustic frequency (and hence allowable bandwidth) is low, special consideration will be e,mployed to balance reliability and bit rate. Another key aspect of this research effort is collaborative beamforming. The student(s), will also solve critical issues in inter-system synchronization leading to demonstrations of ad hoc beamforming from multiple under,water nodes. Time-reversal beamforming will allow multiple platforms to increase gain in the direction that a signal was received. T,his involves solving a problem of time/signal synchronization between systems.UW-APL staff and UW-ECE faculty worked together previo,usly to develop protocols to improve noise rejection in long range underwater acoustic communications which will become a starting p,oint for this project.Outcome - Anticipated outcome of this project is twofold in the introduction of highly skilled engineers into,this dwindling workforce and a significant improvement in the bidirectional communications range of assets in the field.Impact on Do,D Capabilities - A young engineer with an advanced degree and fresh experience solving an acoustics communications challenge such as, this could be expected to continue on to become a Principal Investigator working on DoD or ONR projects for many years to come. The, technology developed could be used to cover a larger area with less assets or communicate with individual assets much farther afiel,d. It could also be used to gather a better understanding of the battlespace informing other systems operations.Approved for Public,Release
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 01, 2022
- Source ID
- N000142212296
Entities
People
- Steven Kahle
Organizations
- Office of Naval Research
- United States Navy
- University of Washington