摘要
海洋电场测量可应用于海洋地质结构探查、海洋矿藏资源勘探、海洋生物监测以及海中、海上运动目标发现追踪。调制式海洋电场传感器由于海洋环境和传感器工作机理,传感输出包含复杂的噪声成分,只有抑制了这些噪声,得到较高的信噪比,才能从传感输出中提取出可靠的电场信号。单一的噪声抑制方法难以有效降低多种噪声,为此本文提出针对调制式海洋电场传感器输出信号中噪声特点的复合去噪方法,将噪声分为宽带随机噪声、有用信号频带内的噪声和有用信号频带外的噪声3类。利用宽带随机噪声与有用信号的不相关性,使用自适应滤波器抑制宽带随机噪声。用带通滤波器抑制有用信号频带外的噪声,最后通过变分模态分解将有用信号从传感输出中提取出来,并通过包络检波实现解调。与单独使用带通滤波去噪、经验模态分解去噪以及小波去噪相比,利用本文方法处理的传感输出信噪比提升了12 dB以上,保证了调制式海洋电场传感信号的可靠解调。
Ocean electric field measurement can be applied to the exploration of marine geological structures,exploration of marine mineral resources,monitoring of marine organisms,and discovery and tracking of moving targets in and at sea.Due to the complexity of the marine environment and the working mechanism of the modulated ocean electric field sensor,the sensing output contains complex noise components.Only by suppressing these noises and obtaining a high signal-to-noise ratio,reliable electric field signals can be extracted from the sensing output.A single noise suppression method is difficult to effectively reduce multiple types of noise.Therefore,this article proposes a composite denoising method targeting the noise characteristics in the output signal of modulated ocean electric field sensors.The noise is divided into three categories,including broadband random noise,noise within the useful signal frequency band,and noise outside the useful signal frequency band.Utilize the uncorrelation between broadband random noise and useful signals,and use adaptive filters to suppress broadband random noise.A bandpass filter is adopted to suppress noise outside the useful signal frequency band.Finally,the useful signal is extracted from the sensing output through variational mode decomposition,and demodulation is achieved through envelope detection.Compared with using bandpass filtering denoising,empirical mode decomposition denoising,and wavelet denoising alone,the sensor output signal-to-noise ratio processed by the proposed method is improved by more than 12 dB,ensuring reliable demodulation of modulated ocean electric field sensing signals.Ocean electric field measurement can be applied to exploration of marine geological structures,exploration of marine mineral resources,monitoring of marine organisms,and discovery and tracking of moving targets in and at sea.Due to the complexity of the marine environment and the working mechanism of the modulated ocean electric field sensor,the sensing output contains complex noise components.Only by suppressing these noises and obtaining a high signal-to-noise ratio can reliable electric field signals be extracted from the sensing output.A single noise suppression method is difficult to effectively reduce multiple types of noise.Therefore,this paper proposes a composite denoising method targeting the noise characteristics in the output signal of modulated ocean electric field sensors.The noise is divided into three categories:broadband random noise,noise within the useful signal frequency band,and noise outside the useful signal frequency band.Utilize the uncorrelation between broadband random noise and useful signals,and use adaptive filters to suppress broadband random noise.Use a bandpass filter to suppress noise outside the useful signal frequency band,and finally extract the useful signal from the sensing output through variational mode decomposition,and achieve demodulation through envelope detection.Compared with using bandpass filtering denoising,empirical mode decomposition denoising,and wavelet denoising alone,the sensor output signal-to-noise ratio processed by the method proposed in this paper has been improved by more than 12 dB,ensuring reliable demodulation of modulated ocean electric field sensing signals.
作者
段震宇
文玉梅
叶敬昌
李平
Duan Zhenyu;Wen Yumei;Ye Jingchang;Li Ping(School of Electronic Information and Electrical Engineering,Shanghai Jiao Tong University,Shanghai 200240,China)
出处
《仪器仪表学报》
EI
CAS
CSCD
北大核心
2024年第10期234-243,共10页
Chinese Journal of Scientific Instrument
基金
国家重点研发计划(2022YFB3205703)项目资助。
关键词
噪声抑制
相关去噪
带通滤波器
VMD
调制式电场传感器
noise suppression
correlation denoising
bandpass filters
VMD
modulated electric field sensor
