• The Journal of the Acoustical Society of Korea
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• v.26 no.8
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• pp.381-389
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• 2007

In this paper, the measuring method of underwater acoustic communication channel characteristics in the shallow water using the autocorrelation characteristic of PN sequence and the undorwater communication channel analysis results from the received signal sample data are described. For measuring the underwater acoustic communication channel characteristics, two PN sequences are used as a transmitted data of I-channel and Q-channel of QPSK symbol and QPSK signal is transmitted with symbol rate of 5 kHz and carrier frequency of 25 kHz. In the receiver the received signal, which pass through 675 m and 1492 m, is sampled and then stored. Using the stored sample data, the scattering function, coherent time, delay power profile, spaced-tone autocorrelation function, delay spread, and coherent bandwidth of each propagation distance cases are analyzed. Based on the analysis results, several guidelines are suggested for the design and implementation of underwater transmission system.