Range-coherent matched field processing (MFP) coherently combines snapshots to localize a moving, narrowband source. This approach differs from existing MFP approaches that treat each snapshot as having a random phase due to both unknown motion through the medium and imprecise knowledge of the source frequency. Range-coherent MFP requires determination of the source phase acquired between snapshots. With that information, MFP can be applied to the cross-spectrum of snapshots acquired at different times, since relative phase between snapshots is determined by the medium properties, source location, and source velocity. Viewed another way, range-coherent MFP is simply MFP applied to a passive synthetic aperture formed from a moving source. The synthetic aperture geometry depends on source velocity, which is included in the MFP search space. Range-coherent MFP produces robust velocity estimates at low signal-to-noise ratio (SNR), which permits the use of a longer fast Fourier transform in pre-processing. The synthetic aperture array gain plus the increased input SNR afforded by the enhanced pre-processing significantly lowers the required signal level for successful localization. In data from the SWellEx-96 experiment, range-coherent MFP successfully localizes a source that is too quiet for conventional methods to localize.

中文翻译：

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用于低信噪比定位的距离相干匹配场处理

距离相干匹配场处理 (MFP) 连贯地组合快照以定位移动的窄带源。这种方法与现有的 MFP 方法不同，现有的 MFP 方法将每个快照视为具有随机相位，这是由于通过介质的未知运动和源频率的不精确知识。范围相干 MFP 需要确定快照之间获取的源相位。有了这些信息，MFP 可以应用于不同时间获取的快照的交叉频谱，因为快照之间的相对相位由介质属性、源位置和源速度决定。从另一个角度来看，距离相干 MFP 只是应用于由移动源形成的无源合成孔径的 MFP。合成孔径几何取决于源速度，它包含在 MFP 搜索空间中。距离相干 MFP 在低信噪比 (SNR) 下产生稳健的速度估计，这允许在预处理中使用更长的快速傅立叶变换。合成孔径阵列增益加上增强的预处理提供的增加的输入 SNR 显着降低了成功定位所需的信号电平。在来自 SWellEx-96 实验的数据中，距离相干 MFP 成功地定位了一个对于传统方法来说太安静而无法定位的源。