发明名称 |
Multi-scale adaptive filter for interferometric SAR data |
摘要 |
Apparatus including a multi-scale adaptive filter for smoothing interferometric SAR (IFSAR) data in areas of low signal-to-noise ratio (SNR) and/or coherence while preserving resolution in areas of high SNR/coherence. The multi-scale adaptive filter uses simple combinations of multiple linear filters applied to a complex interferogram. The multi-scale adaptive filter is computationally efficient and lends itself to parallel implementation. A pyramid architecture comprising a plurality of cascaded stages is employed which reduces the computational load and memory required for implementation of the processing algorithm. The multi-scale adaptive filter implements a processing algorithm that may be applied to standard IFSAR data. Its input is a complex interferogram (the conjugate product of two complex images) and its output is a filtered interferogram ( &upbar& A) which is passed to an information extraction processor, that extracts a terrain elevation map, for example. The adaptive filter incorporates linear filters at two or more scales (i.e. filter impulse response widths) whose outputs are combined in a data-dependent manner. The combination rules result in an output interferogram ( &upbar& A) that is filtered heavily in areas of low coherence and receives little or no filtering in areas of high coherence. The combination rules use a coherence measure that is a simple nonlinear function of the linear filter outputs themselves.
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申请公布号 |
US5488374(A) |
申请公布日期 |
1996.01.30 |
申请号 |
US19940323414 |
申请日期 |
1994.10.14 |
申请人 |
HUGHES AIRCRAFT COMPANY |
发明人 |
FRANKOT, ROBERT T.;HUDSON, RALPH E.;SENGE, GEORGE H. |
分类号 |
G01S7/292;G01S13/90;(IPC1-7):G01S13/90 |
主分类号 |
G01S7/292 |
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