Abstract
The wide-bandwidth capability of nonlinear sonar allows conduction of ocean bottom and sub-bottom investigations at many frequencies. In order to obtain a wide-bandwidth ocean bottom signature spectrum, a system has been implemented which serially translates a coherent frequency source to five different channels, f + Δf, f + 2Δf, f + 3Δf, f + 4Δf, and f + 5Δf. In the ocean, the nonlinear mechanism convolves a second selected primary frequency f with each appearing channel. The low sonar frequencies Δf, …, 5Δf efficiently propagate to large ocean depths. The returning signals provide an ocean bottom and sub-bottom frequency spectrum. Theoretical predictions were presented in the paper “Frequency Scanning Nonlinear Sonar Performance Modeling,” by John A. Birken at the Ocean '74 Conference. In March 1974, William Konrad, NUSC/NL, successfully demonstrated his 0.8-m2-aperture nonlinear array. His empirical data, which were recorded on tapes, provide a source of empirical information to compare with the performance model. Sub-bottom predictions versus frequency have been found to agree significantly with the collected data.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
