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Low Signal-to-noise Ratio Underwater Acoustic Communications
Published
Author(s)
Wen-Bin Yang, T.C. Yang
Abstract
Communications with low input signal-to-noise ratio (SNR) is often called covert communications as the probability of detection and interception decreases with decreasing SNR . Direct-sequence spread-spectrum signaling works at low SNR because of the processing gain derived from the signal time-bandwidth product. The underwater acoustic channel is faced with high multipath spread and rapidly changing channel conditions. Symbol estimation based on the matched filter output is often erroneous based on at-sea data analysis. New algorithms have been proposed and shown to work well with both fixed and moving source data.
Yang, W.
and Yang, T.
(2008),
Low Signal-to-noise Ratio Underwater Acoustic Communications, Sea Technolgy Magazine, [online], https://tsapps.nist.gov/publication/get_pdf.cfm?pub_id=152112
(Accessed October 14, 2025)