宽带声学多普勒流速剖面仪散射回波建模OA
Echo Modeling of Broadband Acoustic Doppler Current Profiler
通过分析宽带声学多普勒流速剖面仪的对流和对底两种工作模式的波束照射区域,采用单位混响体积和单位混响面积替代区域内的散射体,基于混响理论预报模型生成仿真回波声强度,并结合声散射理论分别给出水层散射回波模型和对底散射回波模型的解析式.相较用散射体散射信号叠加的建模方法,该模型用混响体积去代替该区域内所有散射体,大幅减少计算量;同时能准确地预报回波强度,且解析式可直观体现实际环境参数对模型影响,使生成信号更贴近实际情况.设定与实验场地一致的环境参数,模型生成仿真回波信号与实际采集信号对比,在回波强度、概率统计结果以及时域波形上均有良好的一致性.水层散射回波强度预报相对误差<4%,对底散射回波绝对误差<3 dB;仿真回波信号瞬时值和包络分别满足高斯分布和瑞利分布.为验证模型模拟流速准确性与稳定性,重复生成回波信号反复解算多普勒频偏,结果表明相对误差<0.5%,方差<0.7 mm²/s²;同时在不同信噪比下重复验证,明确模型的信噪比适用范围>9 dB场景.
By analyzing the water profiling and bottom track modes of the broadband acoustic Doppler current profiler(BBADCP)beam irradiation areas of the two modes,the scatterers within the area are replaced by the unit reverberation volume or the unit reverberation area.The volume and bottom reverberation theories are adopted to predict the echo acoustic intensity of the proposed model.Based on acoustic scattering theory,analytical expressions are derived for the volume backscattering model and the bottom backscattering model,respectively.Compared with the traditional modeling method based on superposition of scattered signals from discrete scatterers,all scatterers within the irradiation area are characterized by the volume reverberation concept in the proposed model,which effectively reduces the computational complexity.The model can accurately predict the acoustic intensity of echo signals.Furthermore,its analytical expression explicitly reflects the influence of actual environmental parameters,enabling the model-generated signals to be more consistent with real underwater conditions.Under the environmental conditions consistent with the experimental site,the simulated echo signals agree well with the measured data in terms of echo intensity,statistical distribution and time-domain waveform characteristics.The relative error of the predicted water-column backscattering intensity is less than 4%,and the absolute error of the bottom backscattering intensity is less than 3 dB.The instantaneous amplitude and envelope of simulated echoes follow the Gaussian distribution and Rayleigh distribution,respectively.To further verify the accuracy and stability of the model in flow velocity simulation,Doppler shifts are repeatedly estimated using multiple groups of simulated echo signal realizations.The results show that the relative error is lower than 0.5%,and the velocity estimation variance is less than 0.7 mm²/s².Additional tests under different signal-to-noise ratios confirm that the model maintains good applicability when the SNR is above 9 dB.
王吕杰;焦君圣;郭世旭;陶然;史占红;方卫华
中国计量大学 原位计量教育部重点实验室,浙江 杭州 310018中国计量大学 原位计量教育部重点实验室,浙江 杭州 310018中国计量大学 原位计量教育部重点实验室,浙江 杭州 310018南京水利水文自动化研究所,江苏 南京 210012水利部 水文仪器及岩土工程仪器质量监督检验测试中心,江苏 南京 210012南京水利水文自动化研究所,江苏 南京 210012
通用工业技术
宽带声学多普勒流速剖面仪水层散射回波声回波建模对底散射回波混响声强度预报
broadband acoustic Doppler current profilerwater profiling backscattering echoacoustic echo modelingbottom backscattering echoreverberationacoustic intensity prediction
《计量学报》 2026 (5)
702-711,10
国家重点研发计划(2022YFC3204504)
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