Threat detection, identification, and optical counter measures for space-based applications

Abstract

The field of Space Situational Awareness (SSA) has seen increasing interest in recent years. As SSA is covering a wide range of applications, the activities are categorized in three main areas: Space Weather, Near-Earth Objects and Space Surveillance and Tracking (SST). The latter one is covering active and inactive satellites and other man-made objects orbiting Earth. Consequently there are activities focusing on debris and inactive satellites on one hand, which can be seen as maintenance activities allowing humankind long-term access to space. On the other hand, SST covering active satellites is in principle a safety measure for space-based missions. Key words that arise in this context are detection, tracking and identification. These are the key ingredients for in-orbit threat detection. When these ingredients are mastered and dedicated solutions are developed, there is only a small step to go using the gained knowledge and same abilities to perform optical countermeasures.At Jena-Optronik GmbH, we already have a variety of sensors for specific applications in the field of SST available. Our product range covers visible cameras, LiDARs and specific laser detection sensors. Consequently, we recently started increasing our activity in SST to develop dedicated solutions tailored to the specific needs of this application field. Currently, a thermal infrared camera is in development and furthermore we plan to combine all necessary sensors for SST of active satellites in a dedicated SST sensor suite. This suite contains a control electronics unit, which combines all data from the connected sensors to form one data set that covers the satellite surrounding volume and identifies incoming threats. In a next step active sensors can be used to follow incoming threats and hinder them from observing the satellite with the SST sensor suite and in particular its other payloads. This paper will provide an introduction into the topic. It will cover an overview of the concepts and needs for different sensors forming a SST sensor suite. Furthermore, the latest advances in our developments are presented and future steps and activities as well as sensors are motivated.

Optical Phased Array-Based Laser Beam Array Subdivide Pixel Method for Improving Three-Dimensional Imaging Resolution

“…The right sid of Figure 1 shows that the 3D imaging resolution of the LM-APD array can be improved by storing the data acquired in each scan according to the deflection angle at the time o scanning after multiple scans. As shown in Figure 2, assuming that the instantaneous FOV angle of the pixel in the LM-APD array is θ IFOV and the divergence angle of each sub-beam in the beam array is θ sub , our method can maximally increase the number of sampling points by θ 2 IFOV /θ 2 sub times, which means that the spatial resolution of 3D imaging can be increased by θ 2 IFOV /θ 2 sub times. This method allows the beam array to scan simultaneously at each pixel, and the efficiency improvement over single-beam scanning of the unit detector is a multiple of the number of pixels n APD × n APD , which effectively reduces the scanning time.…”

“…Research on laser 3D imaging of non-cooperative targets in space has started in recent years. The German Rendezvous and Docking Sensors (RVSs) pulsed scanning lidar is used for 3D imaging to acquire relative attitude information between the imaging system and the target after more than 40 on-orbit tests [2]. The DragonEye lidar from Advanced Scientific Concepts (ASC) (USA, Goleta), employing the LM-APD array, has been used as the primary sensor for autonomous rendezvous and docking attitude measurements for more than 10 successful autonomous rendezvous missions with the ISS since 2012 [3,4].…”