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In order to obtain the information of elevation which three-dimensional reconstruction needs in the spotlight mode inverse synthetic aperture ladar imaging,a target reconstruction algorithm was designed based on spotlight mode inverse synthetic aperture imaging ladar groups.The systems were placed inverse synthetic aperture ladar in the three vertices of an equilateral triangle.According to the relationship between the position and the inclination angle,the elevation information for reconstructing three-dimensional target could be provided by another two ladars.The elevation functions of three inverse synthetic aperture ladars were calculated when the measured target flied into detects area of the system in any direction.Simulation result shows that the speed of the measured target has no significant effect on the elevation function.Angular relationships of inverse synthetic aperture ladar and target have a significant contribution to the changes in elevation information.In the process of information fusion for different position elevation,the selection of distributed manner for inverse synthetic aperture ladar impacted the utilization of echo data.Because different angles change produces continuous changes in elevation information,this method can effectively reconstruct target three-dimensional image by elevation information obtained.

In order to improve spectrum resolution with the same size of the static Fourier transform interferometer,an orthogonal-wedge static Fourier transform interferometer is designed,which is made up by the two orthogonal-wedge for continuous optical path difference.According to the derivation of the optical path difference function with the tradition static Fourier transform interferometer and the orthogonal-wedge static Fourier transform interferometer,the structure of the two orthogonal-wedge is designed to increase the effective distance of detection for improving spectrum resolution of static interferometer.The simulation results show that the maximum optical path difference of the orthogonal-wedge interferometer is 0.323 4 mm,which is four times better than the traditional interferometer with 0.080 8 mm(optical path difference).Experimental results show that the orthogonal-wedge interferometer has the distortion of the interference fringes as a result of its detection principle,so it needs to be removed and filtering of the edge of the interference fringes.Using the WQF520 type spectrometer to comparative experiment for 800nm laser,the orthogonal-wedge interferometer error is less than 1 nm.This method can effectively improve the spectral resolution of the static Fourier transform interferometer.