# On-Board Parameter Optimization for Space-Based Infrared Air Vehicle Detection Based on ADS-B Data
## 1 Introduction  
The importance of air traffic for increasing the mobility of the population of the served regions is undeniable. Regular air transport is important for industry and logistics, but also for GDP growth [1]. The global airline industry conducted over 36.8 million flights worldwide in 2017, carrying over four billion passengers on scheduled flights. In recent years, frequent aviation safety incidents such as the MH370 crash have caused tremendous economic and life losses and revealed the necessity and strong demand for effective real-time aircraft monitoring on flight routes. The next generation of safety challenges now require the development and understanding of new forms of data to improve safety in other segments of commercial aviation, and moving from a reactive, incident-based approach toward a more proactive, predictive and systems-based approach [2]. Automatic Dependent Surveillance-Broadcast (ADS-B) is a multiparameter surveillance system designed to improve key segments of air traffic: enabling real-time surveillance, raising safety and efficiency levels and improving flight information and weather services [3]. ADS-B data generally contain information such as latitude and longitude, barometric altitude, GPS altitude, speed, heading and aircraft code. Satellites equipped with communication components can receive ADS-Bs in real-time and obtain target flight altitude and speed. In addition to ground-based radar and airborne unmanned vehicle surveillance systems, a space-based surveillance system has great potential for real-time monitoring and wide-range coverage [4]. Space-based air vehicle detection (AVD) systems are based on passive radiation detection and do not require an active response from the target. Hence, they are an effective means of dynamic, global, real-time route monitoring. Under the conditions of space-based observation, it will be affected by earth background clutter, sunlight conditions, atmospheric absorption attenuation and flight status comprehensively. Due to the day and night difference in solar radiation, the radiant intensity of civil aircraft can be reduced by nearly 70% at nighttime, and the difference in background radiance can also decrease by 10 times in the short-wave infrared band. For the above reasons, it is difficult for the conventional space-based infrared detection system to use a set of fixed parameters to meet the stable detection requirement based on different scenarios. Additionally, the time efficiency of the traditional adjustment of detection parameters by sending commands from the ground is too low for time-sensitive target detection such as aircraft. Therefore, the research on reasonable spectral band selection and real-time adjustment of detection system parameters is of great significance. Many researchers have made progress in the following aspects. In the aviation safety aspect, [PERSON] et al. [5] used the open source of ADS-B-based aircraft trajectories, and extracted information to present a framework to detect, identify and characterize anomalies in the past. [PERSON] et al. [6] proposed a space-based ADS-B system and compared the strengths and weaknesses of potential space-based ATS systems. It has an advantage over traditional ground-based systems because it avoids the costly installation and maintenance of ground-based infrastructure while increasing the system's complexity at the same time. [PERSON] et al. [7] integrated a traffic detect and avoid system into remotely piloted unmanned vehicles. The achieved results highlight the appropriate situational awareness provided by the proposed function and its effective support for remote pilots in making adequate decisions in conflict solving. In modeling and experimental measurements on the infrared radiation of military and civil air vehicles, [PERSON] et al. and [PERSON] et al. [8; 9; 10] presented a numerical method based on the finite element method to predict an aircraft's infrared signature.