Return to Session G2b Next Abstract

Session G2b: Resilient and Secure PNT Against Interference and Emerging Threats 1

Real-World Assessment of Hexagon | NovAtel GNSS Anti-Jamming and Anti-Spoofing Technologies
Ali Broumandan, Isabelle Tremblay, Mitchell Palmer, Christian Phillips, Thomas Taylor and Sandy Kennedy, Hexagon | NovAtel
Location: Palm
Date/Time: Wednesday, Sep. 16, 4:00 p.m.

Although various detection and mitigation techniques have been developed to address GNSS threats, additional signal processing often increases system size and power consumption. Recent findings from the GPS Spoofing Workgroup indicate a notable rise in GNSS jamming and spoofing incidents worldwide over the past several years. These threats are no longer limited to military environments; they increasingly affect commercial aviation, maritime navigation, autonomous systems, critical infrastructure, and timing-dependent networks. As GNSS signals are inherently weak when they reach the Earth’s surface, they remain particularly vulnerable to intentional and unintentional interference. GNSS Resilience and Integrity Technology (GRIT) is a firmware suite developed for NovAtel OEM7 receivers to enhance situational awareness and provide advanced interference detection and mitigation capabilities across diverse applications and environments. GRIT protects against GNSS threats, including jamming and spoofing attacks. It incorporates the Interference Toolkit (ITK) and Spoofing Detection Toolkit (SK) to detect and characterize signal threats in real time. NovAtel’s Robust Dual Antenna Receiver (RoDAR), based on a commercial OEM7 dual-antenna platform, employs specialized firmware to mitigate jamming and spoofing without increasing system size or power consumption. This paper presents the advancements and countermeasures implemented in the NovAtel OEM7 special firmware to address real-world GNSS jamming and spoofing attacks. Actual data collected in battlefield and conflict-zone environments are used to characterize spoofing attack behaviors and receiver responses.
In addition, trial results from Jammertest 2025 are presented. During Jammertest 2025, multiple techniques were used to interfere with and manipulate navigation systems in order to mislead participant equipment. These tests included stationary meaconing across all GNSS bands, involving retransmission of live sky signals with incorrect position solutions or small timing delays. Various spoofing techniques were also tested across multiple constellations and frequencies. These included coherent and incoherent stationary spoofers transmitting altered ephemerides (where the broadcast satellite ephemerides differ from live sky data), as well as coherent and incoherent spoofing scenarios using true ephemerides. Some scenarios caused the receiver to report a static false location, while others forced the user onto an incorrect trajectory. In addition to position manipulation, certain scenarios introduced small timing offsets, while others displaced the user’s timing solution by several years into the future. During each meaconing and spoofing scenario, jamming was also introduced, either as a precursor (e.g., five minutes of wideband jamming before spoofing commenced) or as continuous jamming of non-spoofed signals throughout the test.
This paper presents NovAtel receiver jamming and spoofing detection and mitigation performance based on actual data collected during Jammertest 2025 and some additional data collected in conflict-zones. Jamming detection capabilities include spectrum monitoring and interference characterization across all GNSS bands. The effectiveness of the anti-jam and anti-spoofing technologies is demonstrated using representative complex interference scenarios from the event. The NovAtel PwrPak7 receiver was configured for multi-frequency, multi-constellation operation, with position estimation based on all available measurements. The full paper presents detailed test outcomes and receiver behavior under jamming and spoofing conditions. Signal quality monitoring using average C/N? values is analyzed, along with receiver position and timing errors under spoofing attacks. Receiver input power monitoring from ITK logs and real-time spoofing detection results from SK logs are also demonstrated. RoDAR null-steering performance based on a dual-polarized antenna will be demonstrated. Finally, spoofing detection and mitigation performance is compared with that of competitor receivers.

Return to Session G2b Next Abstract