LADAR is a key sensing technology for the relative navigation between a debris-removing satellite and a debris. Compared to cameras and radar, LADAR provides better information about a target’s range, speed, and 3D position. Although LADAR does not need sunlight to operate, it does require more resources on mass, volume, and power (MVP) than a passive sensor. The design of a space LADAR should achieve the required performance with minimum MVP.
This Spotlight describes the operational principle of an instrument based on the LADAR equation and summaries the requirements for debris removal. It discusses key LADAR components, such as lasers, detectors, and scanning optics, in terms of their performance in a space environment. The different types of LADAR are compared under different mission scenarios. A design of a compact space rangefinder is given as an example to explain basic design considerations. A design of an unobstructed 360-deg scanning LADAR is described to illustrate the benefits of a novel design for a mission that requires a wide FOV. Finally, some hybrid concepts that use scanning optics on the launching side and camera optics on the return side are discussed; they utilize the fact that there are no other objects around space debris that contribute solar background signal to gain performance while minimizing the MVP requirements.