Range anomaly suppression based on neighborhood pixels detection in ladar range images

Research on the range anomaly suppression algorithm in laser radar (ladar) range images is significant in the application and development of ladar. But most of existing algorithms cannot protect the edge and linear target well while suppressing the range anomaly. Aiming at this problem, the differences among the edge, linear target, and range anomaly are analyzed and a novel algorithm based on neighborhood pixels detection is proposed. Firstly, the range differences between current pixel and its neighborhood pixels are calculated. Then, the number of neighborhood pixels is detected by the range difference threshold. Finally, whether the current pixel is a range anomaly is distinguished by the neighborhood pixel number threshold. Experimental results show that the new algorithm not only has a better range anomaly suppression performance and higher efficiency, but also protects the edge and linear target preferably compared with other algorithms.     

天基单光子激光雷达危险空间碎片探测仿真

危险空间碎片的探测与监控一直是空间碎片探测的重点与难点,现有的技术还不能实现对危险空间碎片的有效监测与定轨。针对危险空间碎片的探测,研究了一种主动式天基激光雷达探测方式。该方式采用了天基的单光子探测技术,以期实现对几百公里量级的危险空间碎片进行探测。首先简要分析了点目标激光雷达方程,建立了空间环境的背景光噪声模型,探讨了单光子激光雷达的探测概率与虚警率,对激光的回波信号与探测精度进行了理论分析与仿真,最后分析了不同目标的探测能量需求。由理论分析与仿真结果来看,对500 km处的尺寸为10 cm的目标可以实现精度为0.2 m的有效探测。     

Multi-view ladar data registration in obscure environment

Multi-view laser radar (ladar) data registration in obscure environments is an important research field of obscured target detection from air to ground. There are few overlap regions of the observational data in different views because of the occluder, so the multi-view data registration is rather difficult. Through indepth analyses of the typical methods and problems, it is obtained that the sequence registration is more appropriate, but needs to improve the registration accuracy. On this basis, a multi-view data registration algorithm based on aggregating the adjacent frames, which are already registered, is proposed. It increases the overlap region between the pending registration frames by aggregation and further improves the registration accuracy. The experiment results show that the proposed algorithm can effectively register the multi-view ladar data in the obscure environment, and it also has a greater robustness and a higher registration accuracy compared with the sequence registration under the condition of equivalent operating efficiency.     

转动Lambert圆锥激光后向散射Doppler谱的解析解

给出转动Lambert圆锥激光后向散射Doppler谱解析解的数学表达式, 并将解析解和数值解进行比较. 结果表明, 随着数值解计算精度的提高, 数值解和解析解的差值变小, 且解析解和数值解可相互验证.