Based on computed tomography of a Yangtze finless porpoise's biosonar system, a biomimetic structure was designed to include air cavity, gradient-index material, and steel outer-structure mimicking air sacs, melon, and skull, respectively. The mainlobe pressure was about three times higher, the angular resolution was one order of magnitude higher, and the effective source size was orders of magnitude larger than those of the subwavelength source without the biomimetic structure. The superior subwavelength directivity over a broad bandwidth suggests potential applications of this biomimetic projector in underwater sonar, medical ultrasonography, and other related applications. (C) 2014 AIP Publishing LLC.
1.Xiamen Univ, Minist Educ, Key Lab Underwater Acoust Commun & Marine Informa, Xiamen 301005, Peoples R China 2.Xiamen Univ, State Key Lab Marine Environm Sci, Xiamen 361005, Peoples R China 3.Penn State Univ, Dept Math, University Pk, PA 16802 USA 4.Penn State Univ, Mat Res Inst, University Pk, PA 16802 USA 5.Chinese Acad Sci, Inst Hydrobiol, Wuhan 430072, Peoples R China
Zhang, Yu; Gao, Xiaowei; Zhang, Sai; Cao, Wenwu; Tang, Liguo; Wang, Ding; Li, Yan.A biomimetic projector with high subwavelength directivity based on dolphin biosonar,APPLIED PHYSICS LETTERS,2014,():