[Paper Review] GNSS Interference Monitoring from Low Earth Orbit

Matthew J. Murrian, Lakshay Narula+4 more|arXiv (Cornell University)|Sep 9, 2020

GNSS positioning and interference25 references4 citations

TL;DR

This paper proposes using low Earth orbit (LEO) satellites to monitor terrestrial GNSS interference, enabling global characterization of jamming and spoofing signals, including localization of strong interference sources. The study demonstrates the effectiveness of LEO-based monitoring through a three-year analysis, identifying a persistent, high-power interference source in Syria since 2017.

ABSTRACT

Observation of terrestrial GNSS interference (jamming and spoofing) from low-earth orbit (LEO) is a uniquely effective technique for characterizing the scope, strength, and structure of interference and for estimating transmitter locations. Such details are useful for situational awareness, interference deterrence, and for developing interference-hardened GNSS receivers. This paper explores the performance of LEO interference monitoring and presents the results of a three-year study of global interference, with emphasis on a particularly powerful interference source active in Syria since 2017.

Motivation & Objective

• To develop and evaluate a novel method for global GNSS interference monitoring using low Earth orbit (LEO) satellites.
• To characterize the spatial distribution, strength, and temporal behavior of terrestrial GNSS interference.
• To localize and analyze a particularly strong, persistent interference source active in Syria since 2017.
• To support situational awareness and the development of interference-hardened GNSS receivers.

Proposed method

• Utilizes LEO satellites equipped with GNSS signal receivers to detect and record interference signals from Earth's surface.
• Employs signal processing techniques to identify jamming and spoofing signals based on power levels, bandwidth, and signal structure.
• Applies multilateration and time difference of arrival (TDOA) techniques to estimate the geographic location of interference sources.
• Analyzes interference data collected over a three-year period to assess long-term trends and signal behavior.
• Uses signal-to-noise ratio (SNR) degradation and carrier-to-noise density (C/N0) measurements to detect and quantify interference.
• Validates localization accuracy through comparison with known interference sources and signal propagation modeling.

Experimental results

Research questions

• RQ1 How effectively can LEO platforms detect and characterize GNSS interference on a global scale?
• RQ2 What are the spatial and temporal characteristics of persistent interference sources, such as the one in Syria?
• RQ3 Can LEO-based monitoring accurately localize high-power interference transmitters?
• RQ4 How does the strength and structure of interference vary across different geographic regions and over time?

Key findings

• LEO-based monitoring successfully detected and characterized a high-power, persistent GNSS interference source in Syria active since 2017.
• The interference source exhibited consistent signal strength and directional transmission, indicating a fixed, high-gain transmitter.
• The study demonstrated the feasibility of using LEO platforms to locate interference sources with sufficient accuracy for situational awareness.
• Global monitoring revealed regional variations in interference levels, with higher concentrations in conflict-prone or contested regions.
• Signal processing techniques enabled reliable discrimination between jamming and spoofing based on signal characteristics and Doppler shifts.
• The three-year dataset provided evidence of sustained, deliberate interference, suggesting intentional disruption of GNSS services.