Worthmann Brian M, Song H C, Dowling David R
Department of Applied Physics, University of Michigan, Ann Arbor, Michigan 48109, USA.
Marine Physical Laboratory, Scripps Institution of Oceanography, University of California at San Diego, La Jolla, California 92093, USA.
J Acoust Soc Am. 2017 Jan;141(1):543. doi: 10.1121/1.4973955.
Remote source localization in the shallow ocean at frequencies significantly above 1 kHz is virtually impossible for conventional array signal processing techniques due to environmental mismatch. A recently proposed technique called frequency-difference matched field processing (Δf-MFP) [Worthmann, Song, and Dowling (2015). J. Acoust. Soc. Am. 138(6), 3549-3562] overcomes imperfect environmental knowledge by shifting the signal processing to frequencies below the signal's band through the use of a quadratic product of frequency-domain signal amplitudes called the autoproduct. This paper extends these prior Δf-MFP results to various adaptive MFP processors found in the literature, with particular emphasis on minimum variance distortionless response, multiple constraint method, multiple signal classification, and matched mode processing at signal-to-noise ratios (SNRs) from -20 to +20 dB. Using measurements from the 2011 Kauai Acoustic Communications Multiple University Research Initiative experiment, the localization performance of these techniques is analyzed and compared to Bartlett Δf-MFP. The results show that a source broadcasting a frequency sweep from 11.2 to 26.2 kHz through a 106 -m-deep sound channel over a distance of 3 km and recorded on a 16 element sparse vertical array can be localized using Δf-MFP techniques within average range and depth errors of 200 and 10 m, respectively, at SNRs down to 0 dB.
由于环境失配问题，对于传统阵列信号处理技术而言，在浅海环境中以显著高于1kHz的频率进行远程源定位几乎是不可能的。最近提出的一种称为频差匹配场处理（Δf-MFP）的技术[沃思曼、宋和道林（2015年）。《美国声学学会杂志》138(6)，3549 - 3562页]通过利用频域信号幅度的二次乘积（称为自乘积）将信号处理转移到信号频段以下的频率，克服了环境知识不完善的问题。本文将这些先前的Δf-MFP结果扩展到文献中发现的各种自适应MFP处理器，特别强调在-20至+20 dB的信噪比下的最小方差无失真响应、多约束方法、多重信号分类和匹配模式处理。利用2011年考艾岛声学通信多大学研究计划实验的测量数据，分析了这些技术的定位性能，并与巴特利特Δf-MFP进行了比较。结果表明，一个通过106米深的声道在3公里距离上广播从11.2至26.2 kHz扫频信号并记录在16元稀疏垂直阵列上的源，使用Δf-MFP技术在信噪比低至0 dB时，平均距离和深度误差分别可控制在200米和10米以内。
