Computation of bit error rate for underwater communication with and without low-salinity water in the western sea of Jeju

• Published in: The Journal of the Acoustical Society of America 2011-04, Vol.129 (4_Supplement), p.2667-2667
• Main Authors: Bok, Tae-Hoon, Kim, Juho, Paeng, Dong-Guk, Lee, Chong Hyun, Bae, Jinho, Pang, Ig-Chan, Kim, Seongil
• Format: Article
• Language: English
• ISSN: 0001-4966; 1520-8524
• DOI: 10.1121/1.3588926

Salinity is one of variables in the empirical formula of the sound speed (SS) of seawater. Its effects on the SS are generally neglected because the average salinity is 34 psu and varies within a few psu seasonally and spatially in the ocean. Recently, low-salinity water around 25 psu flows into the western sea of Jeju Island in Korea due to the Yangtze River flood in China during summer. In this paper, it was analyzed how the low-salinity water affected the SS profile (SSP) and the underwater communication. The SSP was calculated with and without the low-salinity layer, and the communication channel was estimated by the simulated acoustic eigen-rays. The bit error rate (BER) was computed using binary phase-shift keying modulation, and the effects of the low-salinity water on the BER were investigated. The SSP was changed to a positive slope by the low-salinity layer at the sub-surface up to 20 m of depth, forming the acoustic wave guide which mostly resulted in the decrease of the BER. Consequently, this paper suggests that it is important to consider the low-salinity water near Jeju for the underwater acoustic modeling and communication. [Work supported by UD100014DD.]