Resampling technique in the orthogonal direction for down-looking Synthetic Aperture Imaging Ladar

The implementation of down-looking Synthetic Aperture Imaging Ladar(SAIL) uses quadratic phase history reconstruction in the travel direction and linear phase modulation reconstruction in the orthogonal direction. And the linear phase modulation in the orthogonal direction is generated by the shift of two cylindrical lenses in the two polarization-orthogonal beams. Therefore, the fast-moving of two cylindrical lenses is necessary for airborne down-looking SAIL to match the aircraft flight speed and to realize the compression of the orthogonal direction, but the quick start and the quick stop of the cylindrical lenses must greatly damage the motor and make the motion trail non-uniform. To reduce the damage and get relatively well trajectory, we make the motor move like a sinusoidal curve to make it more realistic movement, and through a resampling interpolation imaging algorithm, we can transform the nonlinear phase to linear phase, and get good reconstruction results of point target and area target in laboratory. The influences on imaging quality in different sampling positions when the motor make a sinusoidal motion and the necessity of the algorithm are analyzed. At last, we perform a comparison of the results of two cases in resolution.

[1]  刘立人 Liu Liren.  Principle of Down-Looking Synthetic Aperture Imaging Ladar , 2012 .

[2]  孙建锋 Sun Jianfeng,et al.  Imaging Algorithm of Fresnel Telescope Based on Resampling Interpolation , 2011 .

[3]  周煜 Zhou Yu,et al.  2D Imaging Experiment of a 2D Target in a Laboratory-Scale Synthetic Aperture Imaging Ladar , 2009 .

[4]  Liren Liu,et al.  Laboratory demonstration of static-mode down-looking synthetic aperture imaging ladar , 2015 .

[5]  L. Rickard,et al.  Two-dimensional synthetic aperture imaging in the optical domain. , 2002, Optics letters.

[6]  Steven M Beck,et al.  Synthetic-aperture imaging laser radar: laboratory demonstration and signal processing. , 2005, Applied optics.

[7]  Liren Liu.  Coherent and incoherent synthetic-aperture imaging ladars and laboratory-space experimental demonstrations [Invited]. , 2013, Applied optics.

[8]  周煜 Zhou Yu,et al.  Influence of inner wave-front aberration on down-looking synthetic aperture imaging ladar imaging , 2014 .

[9]  周煜 Zhou Yu,et al.  Two-Dimensional Imaging Experiment of Down-Looking Synthetic Aperture Ladar under Simulated Far-Field Conditions , 2014 .

[10]  周煜 Zhou Yu,et al.  Demonstration of a Laboratory Fresnel Telescope Synthetic Aperture Imaging Ladar , 2012 .

[11]  L. J. Landau.  Ratios of Bessel Functions and Roots of αJν(x) + xJ′ν(x) = 0 , 1999 .

[12]  Joe Buck,et al.  Synthetic aperture ladar flight demonstration , 2011, CLEO: 2011 - Laser Science to Photonic Applications.

[13]  Liren Liu,et al.  Down-looking synthetic aperture imaging ladar demonstrator and its experiments over 1.2 km outdoor , 2014 .

[14]  周煜 Zhou Yu,et al.  Electrically Controlled Parabolic Wavefront Scanner in Down-Looking Synthetic Aperture Imaging Ladar , 2014 .

[15]  周煜 Zhou Yu,et al.  A Large-Aperture Synthetic Aperture Imaging Ladar Demonstrator and Its Verification in Laboratory Space , 2011 .

[16]  Yu Zhou,et al.  Speckle effect in a down-looking synthetic aperture imaging ladar , 2014, Optics & Photonics - Optical Engineering + Applications.