发明名称 |
Auto-focusing correction for rotational acceleration effects on inverse synthetic aperture radar images |
摘要 |
Inverse synthetic aperture radar imaging systems that are used to image targets that undergo rotational accelerations are enhanced by signal processing techniques which provide correction factors to reduce the frequency-shift and frequency-stretch errors that occur due to such accelerations. A target scan is subdivided into a number of sub-apertures and a Fast Fourier Transfer (FFT) is performed on the data for each sub-aperture to provide associated frequency sub-images. The FFT is then subdivided in "sub-swaths" of amplitude versus frequency for a plurality of frequency bands. The change-of-frequency, or frequency shift, data between prominent scattering points of each sub-image are processed to provide a phase correction factor that incorporates range changes and translational acceleration distortions for additional scattering points other than the most prominent scattering point. A frequency-stretch correction factor that compensates for rotational acceleration distortion is also provided.
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申请公布号 |
US5343204(A) |
申请公布日期 |
1994.08.30 |
申请号 |
US19930098917 |
申请日期 |
1993.07.29 |
申请人 |
UNISYS CORPORATION |
发明人 |
FARMER, MICHAEL E.;HATLESTAD, JOHN D. |
分类号 |
G01S13/90;(IPC1-7):G01S13/90 |
主分类号 |
G01S13/90 |
代理机构 |
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