The objective of this work is to study the multipath underwater channel characteristics by estimating the channel impulse response and its derived functions such as scattering functions, power delay profile and Doppler spread. This work performs the channel characterization from the data measured from south- west Bay of Bengal during July 2017 at a range of about 1 km and 3 km in a depth of approximately 20 m. To estimate the channel impulse response, Linear Frequency Modulated (LFM) pulse with the bandwidth of 4 kHz and the center frequency of 11 kHz is used as a probe signal. Experimental data analysis shows the variations between two channels of 1 km and 3 km ranges. Other characterization functions such as multipath intensity profile and Doppler power spectrum are estimated from the channel impulse response. The estimated channel parameters convey that the channels are quasi stationary and the Doppler frequency spreads are due to the movement of the transmitter and receiver positions.

中文翻译：

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水下声通信通道的表征

这项工作的目的是通过估计信道脉冲响应及其派生函数（例如散射函数，功率延迟分布和多普勒扩展）来研究多径水下信道特性。这项工作是根据2017年7月从孟加拉湾西南湾测得的数据进行的信道表征，其范围约为1 km和3 km，深度约为20 m。为了估算信道脉冲响应，将带宽为4 kHz，中心频率为11 kHz的线性调频（LFM）脉冲用作探测信号。实验数据分析显示了1 km和3 km范围的两个通道之间的变化。根据信道脉冲响应，可以估算其他表征功能，例如多径强度分布和多普勒功率谱。