3种主动合成孔径成像技术极限探测能力的分析与比较

为了深入研究可行的中高轨成像技术,本文从探测能力角度(用最低发射激光功率表示)深入分析和比较3种主动干涉合成孔径成像技术——傅立叶望远镜(又称为相干场成像或条纹场扫描成像)、成像相关术(又称为强度相关成像)和剪切光束成像。本文利用光电倍增管的信噪比模型和激光作用距离方程,较为细致地分析每种技术在满足单次信噪比(SNR=5)条件下的极限探测能力。通过仿真分析得出:傅立叶望远镜、成像相关术和剪切光束成像所需的最低单光束单脉冲能量分别为11. 4 J、0. 73 MJ和3. 1 MJ。最终得出傅立叶望远镜是上述3种主动成像技术中在目前技术水平下最适合中高轨目标(约36 000 km)高分辨成像的可用技术的结论。

Analysis and comparison of limit detection capabilities of three active synthetic aperture imaging techniques

In order to deeply study the feasibility GEO imaging techniques, this paper deeply analyzes and compares three techniques for active interferometric synthetic aperture imaging by means of sensitivity. These techniques are Fourier telescopy, imaging correlography and sheared-beam imaging. Using a SNR(signal to noise ratio) model for photomultiplier tubes and laser range equations, this paper gives a detailed analysis of the limit detection capability of each technique when SNR is 5. Through simulation, it was found that the lowest single pulse energies for Fourier telescopy, imaging correlography and sheared-beam imaging were 11.4 J, 0.73 MJ and 3.1 MJ, respectively. The conclusion is that Fourier telescopy is the best among these three imaging techniques, making it most suitable for GEO imaging in the present era.