Kameron Simon, Kratos; Steve Williams, Kratos; Ian Hersom, Kratos
Keywords: Passive RF, LEO
Abstract:
In today’s already contested and congested space environment, the proliferation of Low Earth Orbit (LEO) satellites only increases the need to identify, characterize, and track satellites to maintain Space Domain Awareness (SDA). This paper will explore applying passive RF techniques that could be used to uniquely identify, characterize, and track objects in LEO.
Traditional techniques utilize electro-optical and radar sensors, but each of these have their own advantages and limitations. Electro-optical techniques may perform well during the night but become less efficient during daylight, inoperable during cloudy conditions, and are hampered by lightning strikes. Electro-optical sensors also have a difficult time distinguishing between objects of similar size (i.e., cubesat visual magnitudes are like each other). Satellites now have a preponderance of sunshades or are being painted black as to not impact astronomers as seen with Space X. This makes it next to impossible for electro-optical techniques to identify or track these objects. While radar is generally effective in all-weather conditions, day or night, it has difficulty distinguishing between objects of similar size and shape (i.e., cubesat radar cross-sections are very similar to each other). Passive RF can perform in all-weather conditions, day or night and can uniquely identify objects even if they are the same in size, shape, and brightness – but is only able to track active objects that are transmitting.
Since all active satellites transmit a signal to either provide TT&C or communications, this paper will explore how passive RF can be used to blind-scan satellites to identify and characterize the signals being transmitted from the satellite. The methods explored in this paper could be useful in uniquely identifying satellites that are launched in large clusters. The paper will additionally explore a method to track the signals identified for a particular satellite and use that information to create or refine an orbital state vector. The conclusion of this paper will show how passive RF helps SDA to identify, characterize and track satellites in LEO constellations from launch through the satellite’s end of life.
Date of Conference: September 27-20, 2022
Track: Astrodynamics