Signal processing concepts for small and large scale UAVs

In this report we discuss two ladar sensor concepts for mounting unmanned aerial vehicles (UAV). The discussion is based on known performance in commercial ladar systems today and predicted performance in future UAV applications. The UAV systems include one small with similar size as the SwAF systems Korpen and Falken and a large UAV with size similar to SwAF systems Örnen and Ugglan. The small UAV may only carry a few kg of equipment in total, and is equipped with a short-range scanning ladar, visual camera, camera operating in the infrared (IR) wavelengths, and a GPS-based navigation system with accuracy within a few meters. The system is aimed for quick situational analysis of small areas and for documentation of a situation. Maximum altitude is approximately 100 meters. The large UAV may carry a heavier load and is equipped with a high-performing photon counting ladar with matrix detector, visual camera, IR camera, and a GPS-based navigation system with accuracy within a few decimeters. Its purpose is to support large-area surveillance, intelligence and mapping operations. Typical altitude is approximately 1000 meters. Based on these sensors and their performance, signal and image processing support for data analysis is analyzed. The purpose of the data processing is to condense information, in order to facilitate human decision making. Generated data amounts are estimated and demands on data storage capacity and data transfer is analyzed. We predict that after commercial development of the full UAV systems the speeds of data processing and transmission can be reduced to real time or near real time. It is proposed that FOI should study the ladar concepts further, to be able to verify (or reject) the current conclusions. FOI evaluates a test platform where parts of the concepts can be studied further, for example to scrutinize the suggested signal processing chain. In the large UAV a new generation of ladar is suggested, that uses a new measurement principle and that put new demands on noise reduction. In this case we need to extend FOIs knowledge about this type of data processing as a whole, which can be performed on simulated data and measurements in controlled environments.