Surface wave focusing and acoustic communications in the surf zone
MetadataShow full item record
KeywordUnderwater acoustic communication; Underwater acoustic propagation; Acoustic focusing; Acoustic wave refraction; Direction-of-arrival estimation; Acoustic signal processing
The forward scattering of acoustic signals off of shoaling surface gravity waves in the surf zone results in a time-varying channel impulse response that is characterized by intense, rapidly fluctuating arrivals. In some cases, the acoustic focusing by the curvature of the wave crest results in the formation of caustics at or near a receiver location. This focusing and the resulting caustics present challenges to the reliable operation of phase coherent underwater acoustic communications systems that must implicitly or explicitly track the fluctuations in the impulse response. The propagation physics leading to focusing are studied with both experimental data and a propagation model using surface wave profiles measured during the collection of the experimental data. The deterministic experimental and modeled data show good agreement and demonstrate the stages of the focusing event and the impact of the high intensity arrivals and rapid fluctuations on the ability of an algorithm to accurately estimate the impulse response. The statistical characterization of experimental data shows that the focusing by surface gravity waves results in focused surface reflected arrivals whose intensity often exceeds that of the direct arrival and the focusing and caustic formation adversely impacts the performance of an impulse response estimation algorithm.
Author Posting. © Acoustical Society of America, 2004. This article is posted here by permission of Acoustical Society of America for personal use, not for redistribution. The definitive version was published in Journal of the Acoustical Society of America 116 (2004): 2067-2080, doi:10.1121/1.1771591.
Suggested CitationArticle: Preisig, James C., Deane, Grant B., "Surface wave focusing and acoustic communications in the surf zone", Journal of the Acoustical Society of America 116 (2004): 2067-2080, DOI:10.1121/1.1771591, https://hdl.handle.net/1912/2907
Showing items related by title, author, creator and subject.
Estimated communication range and energetic cost of bottlenose dolphin whistles in a tropical habitat Jensen, Frants H.; Beedholm, Kristian; Wahlberg, Magnus; Bejder, Lars; Madsen, Peter T. (Acoustical Society of America, 2012-01)Bottlenose dolphins (Tursiops sp.) depend on frequency-modulated whistles for many aspects of their social behavior, including group cohesion and recognition of familiar individuals. Vocalization amplitude and frequency ...
Performance analysis of adaptive equalization for coherent acoustic communications in the time-varying ocean environment Preisig, James C. (Acoustical Society of America, 2005-07)Equations are derived for analyzing the performance of channel estimate based equalizers. The performance is characterized in terms of the mean squared soft decision error of each equalizer. This error is decomposed into ...
Bohner, Christopher George (Massachusetts Institute of Technology and Woods Hole Oceanographic Institution, 2003-09)A novel distributed underwater acoustic networking (UAN) protocol suitable for ad-hoc deployments of both stationary and mobile nodes dispersed across a relatively wide coverage area is presented. Nodes are dynamically ...