Abstract:
In order to achieve the remote application of inverse synthetic aperture laser radar for high resolution spatial situational awareness, it is essential to analyze the main factors that restrict its remote application. This study combines the range equation of inverse synthetic aperture lidar with the stimulated Brillouin threshold power equation to investigate the variation of laser transmitting power with distance. Additionally, by utilizing the excited Brillouin threshold power equation, laser linewidth formula, and pulse width characteristics of pulse signal, we examine the variation law of laser coherence that meets corresponding power requirements at different distances. The results indicate that a detection distance of 22 km and below can be achieved using continuous fiber lasers without compensation. Coherence compensation is necessary for distances between 22 km and 57 km. For distances ranging from 57 km to 3000 km, pulsed solid-state lasers are used to analyze coherence and conclude that imaging non-cooperative targets within this range is feasible. It is observed that coherence compensation is required from 57 km to 2179 km, becoming more challenging after 2000 km. Furthermore, pulsed solid-state lasers can still be utilized for imaging cooperative targets within a range of 2179-3273 km; however, coherence compensation remains necessary and becomes increasingly difficult. Finally, several coherent length compensation schemes are proposed in order to extend the imaging range of inverse synthetic aperture LiDAR to approximately 3000 km.
摘要:
为了实现逆合成孔径激光雷达对高分辨率空间态势感知的远程应用,分析制约其远程应用的主要因素至关重要。本研究将逆合成孔径激光雷达的距离方程与受激布里渊阈值功率方程相结合,研究了激光发射功率随距离的变化。此外,利用激励布里渊阈值功率方程,激光线宽公式,和脉冲信号的脉冲宽度特性,我们研究了在不同距离下满足相应功率要求的激光相干性的变化规律。结果表明,使用连续光纤激光器可以实现22km及以下的检测距离,而无需补偿。对于22km和57km之间的距离,必须进行相干补偿。距离从57公里到3000公里,脉冲固体激光器用于分析相干性,并得出结论,在该范围内成像非合作目标是可行的。据观察,从57公里到2179公里需要相干补偿,2000公里后变得更具挑战性。此外,脉冲固态激光器仍可用于2179-3273km范围内的合作目标成像;然而,一致性补偿仍然是必要的,并且变得越来越困难。最后,为了将逆合成孔径激光雷达的成像范围扩展到约3000km,提出了几种相干长度补偿方案。