On-Board Interference Detection And Localization For Satellite Communication

Interference is identified as a critical issue for satellite communication (SATCOM) systems and services. There is a growing concern in the satellite industry to manage and mitigate interference efficiently. In this context, an on-board spectrum monitoring and localization unit can be used to detect and localize the interference reliably. Current satellite spectrum monitoring and localization units are deployed on the ground, and the introduction of an in-orbit spectrum monitoring and localization unit can bring several benefits, e.g., simplifying the ground-based station in multibeam systems. This chapter presents the interference detection and localization techniques which take place on-board the satellite within a digital transparent processor (DTP) satellite payload or in a partially regenerative satellite. First, the conventional energy detector (CED) is presented, which is an efficient technique to monitor strong interference in SATCOMs. However, weak interference is not so easily detectable because of its low interference-to-signal-plus-noise ratio (ISNR). To address this issue, a second detector is discussed, which exploits the frame structure and pilot symbols of the SATCOM standards. Assuming that the pilot signal is known at the receiver, it can be removed from the total received signal, and then, an ED technique can be applied on the remaining signal to decide on the presence or absence of interference. Nevertheless, the detection at low values of ISNR may require more samples than the number of pilots supported by the standards. For this reason, a third detector is introduced by demodulating the desired signal, removing it from the total received signal and applying an ED in the remaining signal for the detection of interference. After detecting the interference, the interferer needs to be localized and, hence, this chapter describes the current techniques for on-ground interference localization and presents an on-board interference localization technique using frequency of arrival (FoA) via a single satellite.