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Hiroshi Ochi,Yoshitaka Watanabe,Takuya Shimura,Takehito Hattori 제어로봇시스템학회 2009 제어로봇시스템학회 국제학술대회 논문집 Vol.2009 No.8
To achieve high-speed acoustic data transmission, the use of a frequency band of 80 ± 20 kHz is being considered. However, the absorption attenuation coefficient in these frequencies only has empirical formula. Therefore,the absorption attenuation was measured using the frequency of 60 to 100 kHz within the propagation distance of 530 to 700 m at approximately 1,000 m depth. The transmission signal wave form was measured with conductivity,temperature, and depth (CTD) data. From these measured data, the absorption attenuation coefficient was calculatedusing several empirical equations. Calculated value of absorption attenuation coefficients by using measured signal were compared with calculated value by several empirical equations. As a result, a corresponding comparatively good for the empirical formula of Francois and Garrison.