Dim target detection from sea clutter is one of the difficult topics in ocean remote sensing application. By aiming at the shortcoming of false alarms when using track before detect （TBD） based on dynamic programmin...Dim target detection from sea clutter is one of the difficult topics in ocean remote sensing application. By aiming at the shortcoming of false alarms when using track before detect （TBD） based on dynamic programming, a new discrimination method called statistics of direction histogram （SDH） is proposed, which is based on different features of trajectories between the true target and false one. Moreover, a new series of discrimination schemes of SDH and Local Extreme Value method （LEV） are studied and applied to simulate the actually measured radar data. The results show that the given discrimination is effective to reduce false alarms during dim targets detection.展开更多
太平洋磷虾是黄海生态系统中浮游动物的关键种。为准确评估太平洋磷虾的资源密度,基于2010年1月黄海渔业资源调查过程中采集的声学和生物学数据,利用SDWBA目标强度理论模型,研究了太平洋磷虾38和120 k Hz目标的回声散射特性,并根据2个...太平洋磷虾是黄海生态系统中浮游动物的关键种。为准确评估太平洋磷虾的资源密度,基于2010年1月黄海渔业资源调查过程中采集的声学和生物学数据,利用SDWBA目标强度理论模型,研究了太平洋磷虾38和120 k Hz目标的回声散射特性,并根据2个频率平均体积散射强度的差值(简称频差技术),开展了太平洋磷虾回波映像识别及资源密度评估研究。结果显示,太平洋磷虾的目标强度与其倾角和体长密切相关;120k Hz的目标强度明显高于38 k Hz,且两个频率的有效平均目标强度之差随着磷虾体长的增加而减小。数据处理结果显示,两个频率回声数据的平均体积散射强度(MVBS)呈线性关系,120 k Hz的MVBS比38 k Hz高约14.1 d B,与理论仿真结果一致;回声散射层内太平洋磷虾的资源密度为1.8~2531.8尾/m3,均值为255.1尾/m3。本研究对利用渔业声学技术开展浮游动物资源评估具有借鉴意义,未来还需要进一步对太平洋磷虾目标强度模型参数及目标识别方法进行完善,以提高其资源密度声学评估的准确度。展开更多
基金supported by the National Natural Science Foundation of China(Grant No.61001137)the Pre-Research Foundation(Grant No.9140A07020311HK0116)
文摘Dim target detection from sea clutter is one of the difficult topics in ocean remote sensing application. By aiming at the shortcoming of false alarms when using track before detect （TBD） based on dynamic programming, a new discrimination method called statistics of direction histogram （SDH） is proposed, which is based on different features of trajectories between the true target and false one. Moreover, a new series of discrimination schemes of SDH and Local Extreme Value method （LEV） are studied and applied to simulate the actually measured radar data. The results show that the given discrimination is effective to reduce false alarms during dim targets detection.
文摘太平洋磷虾是黄海生态系统中浮游动物的关键种。为准确评估太平洋磷虾的资源密度,基于2010年1月黄海渔业资源调查过程中采集的声学和生物学数据,利用SDWBA目标强度理论模型,研究了太平洋磷虾38和120 k Hz目标的回声散射特性,并根据2个频率平均体积散射强度的差值(简称频差技术),开展了太平洋磷虾回波映像识别及资源密度评估研究。结果显示,太平洋磷虾的目标强度与其倾角和体长密切相关;120k Hz的目标强度明显高于38 k Hz,且两个频率的有效平均目标强度之差随着磷虾体长的增加而减小。数据处理结果显示,两个频率回声数据的平均体积散射强度(MVBS)呈线性关系,120 k Hz的MVBS比38 k Hz高约14.1 d B,与理论仿真结果一致;回声散射层内太平洋磷虾的资源密度为1.8~2531.8尾/m3,均值为255.1尾/m3。本研究对利用渔业声学技术开展浮游动物资源评估具有借鉴意义,未来还需要进一步对太平洋磷虾目标强度模型参数及目标识别方法进行完善,以提高其资源密度声学评估的准确度。
