Underwater acoustic communication channel simulation using parabolic equation
Underwater acoustic communication channel simulation using parabolic equation
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DOI：
10.1145/2076569.2076571
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发表时间：
2011-10
期刊：
影响因子：
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通讯作者：
A. Song;Joseph Senne;M. Badiey;Kevin B. Smith
中科院分区：
文献类型：
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作者：
A. Song;Joseph Senne;M. Badiey;Kevin B. Smith
高频声通信（8—50khz）是近年来备受关注的一个领域。在数据速率、通信范围和性能方面取得了重大进展。在这些高频率下，各种物理过程，包括表面波、地下气泡和海洋体积波动，可以显著影响通信信道。时变水下信道具有确定性和随机性的双重特征。虽然正在进行的工作，研究界仍然缺乏足够的模型，可以提供海洋动态通道的现实表现。水声通信技术的发展主要依靠海上实验，而海上实验成本很高。一个真实的信道模型不仅可以方便接收机的设计，帮助研究信道限制，有助于通信算法的验证和比较，还可以为网络层面的研究提供基础。利用声波传播和散射的抛物方程模型，研制了通信信道模拟器。具体来说，模拟器使用蒙特雷-迈阿密抛物方程模型（MMPE）和线性表面模型。线性表面模型基于理论或实验方向表面谱生成一个演化表面，并将表面位移及其导数输入声学模型。当地层发生变化时，利用连续的MMPE计算时变声场。在每一次运行中，该模型根据表面输入来考虑表面散射效应。它还考虑了通过水柱和沉积物的传播，这些传播基于其他环境测量，如声速剖面、水深测量和底部特性。并利用2008年太平洋海域的实验数据对航道模拟器进行了标定。表面模型根据实验中乘波浮标获得的方向表面谱模拟了一个随时间变化的表面。基于表面输入和其他环境测量，信道模拟器产生真实的时变脉冲响应。在到达时间结构和强度分布方面，输出与声学测量结果吻合良好。实验数据和模拟数据的声学通信性能比较也将在会议上报告。
High frequency acoustic communication (8--50 kHz) has attracted much attention recently. Significant advancements have been achieved in terms of data rates, communication range, and performance. At these high frequencies, various physical processes, including surface waves, subsurface bubbles, and ocean volume fluctuations, can significantly affect the communication channel. The time-varying underwater channel has both deterministic and stochastic features. While there is on-going work, the research community is still lacking adequate models that can provide realistic representations of the dynamic channel in the ocean. Advancements in underwater acoustic communication technology mainly rely on at-sea experiments, which are very costly. A realistic channel model not only can facilitate receiver design, help investigate channel limits, and aid in communication algorithm validation and comparison, it also can provide a basis for network level studies. A communication channel simulator is developed here through the use of parabolic equation modeling of acoustic propagation and scattering. Specifically, the simulator uses the Monterey-Miami Parabolic Equation model (MMPE) augmented with a linear surface model. The linear surface model generates an evolving surface based on theoretical or experimental directional surface spectrum and feed the surface displacement and its derivatives to the acoustic model. The time-varying acoustic field is calculated using successive MMPE runs when the surface evolves. At each single run, the model accounts for surface scattering effects based on the surface input. It also accounts for propagation through the water column and through the sediment based on other environmental measurements such as sound speed profile, bathymetry, and bottom properties. The channel simulator is also calibrated by experimental data obtained in the Pacific ocean in 2008. The surface model simulates a time-evolving surface from the directional surface spectrum obtained by a Waverider buoy in the experiment. Based on the surface input and other environmental measurements, the channel simulator generates realistic time-varying impulse responses. The output agreed well with the acoustic measurements in terms of arrival time structure and intensity profile. Acoustic communication performance comparison between the experimental and simulated data will be also reported in the conference.