物理学报
物理學報
물이학보
2015年
9期
094302-1-094302-9
,共1页
水下目标回波%弹性声散射%声散射信号分离
水下目標迴波%彈性聲散射%聲散射信號分離
수하목표회파%탄성성산사%성산사신호분리
underwater target echo%elastic acoustic scattering%acoustic scattering signal separation
水下目标弹性声散射与其他声散射成分在时域和频域上均存在混叠，现有信号处理方法受分辨力限制无法在混叠状态下识别目标弹性声散射特征。针对这个问题，提出了一种目标弹性声散射信号分离方法。以目标回波亮点模型为基础，分析了线性调频信号入射时目标声散射成分的信号特性，提出了一种目标声散射成分向单频信号的映射方法，并理论推导出了目标声散射结构与映射结果之间的线性对应关系，实现了通过窄带滤波分离出目标弹性声散射成分。仿真与消声水池实验数据处理结果表明，该方法基本可以完全分离出目标回波信号中的弹性声散射成分，分离出的弹性声散射具有与理论一致的信号特征，验证了该分离方法的有效性。
水下目標彈性聲散射與其他聲散射成分在時域和頻域上均存在混疊，現有信號處理方法受分辨力限製無法在混疊狀態下識彆目標彈性聲散射特徵。針對這箇問題，提齣瞭一種目標彈性聲散射信號分離方法。以目標迴波亮點模型為基礎，分析瞭線性調頻信號入射時目標聲散射成分的信號特性，提齣瞭一種目標聲散射成分嚮單頻信號的映射方法，併理論推導齣瞭目標聲散射結構與映射結果之間的線性對應關繫，實現瞭通過窄帶濾波分離齣目標彈性聲散射成分。倣真與消聲水池實驗數據處理結果錶明，該方法基本可以完全分離齣目標迴波信號中的彈性聲散射成分，分離齣的彈性聲散射具有與理論一緻的信號特徵，驗證瞭該分離方法的有效性。
수하목표탄성성산사여기타성산사성분재시역화빈역상균존재혼첩，현유신호처리방법수분변력한제무법재혼첩상태하식별목표탄성성산사특정。침대저개문제，제출료일충목표탄성성산사신호분리방법。이목표회파량점모형위기출，분석료선성조빈신호입사시목표성산사성분적신호특성，제출료일충목표성산사성분향단빈신호적영사방법，병이론추도출료목표성산사결구여영사결과지간적선성대응관계，실현료통과착대려파분리출목표탄성성산사성분。방진여소성수지실험수거처리결과표명，해방법기본가이완전분리출목표회파신호중적탄성성산사성분，분리출적탄성성산사구유여이론일치적신호특정，험증료해분리방법적유효성。
An elastic acoustic scattering by underwater target could be mixed with other acoustic scattering components in both time and frequency domains, and the existing signal processing methods could not discriminate the elastic feature of target in the mixed status. For solving this problem, a signal separation method for elastic acoustic scattering is proposed. Based on the highlight model of target echo, the characters of the target acoustic scattering signal when the linear frequency modulation signal is transmitted, are analyzed, and a method for mapping the acoustic scattering signal of the target to a single frequency signal is proposed. Theoretical derivation shows that there is a simple linear relationship between the acoustic scattering structure of the target and the mapped result, then the elastic acoustic scattering signal of the target can be separated by a narrow-band filtering. Simulation results show that the correlation coe?cient between the separated target acoustic scattering and the orginal simulation signals are about 0.99, indicating that the acoustic scattering components in the simulation target echo can be wholly separated. Experimental data-processing results of the target acoustic scattering measurement in an anechoic pool show that the mid-frequency enhancement effect can be observed in the spectrum of the separated elastic acoustic scattering, and every target acoustic scattering component can be recognized on the time-frequency distribution of separately processed target echo. There is a bowl-shape interference fringe on the angle-spectrum of the separated target elastic acoustic scattering components which is consistent with the theoretical signal’s feature of the elastic acoustic scattering, and the effectiveness of the separation method proposed is proven.
