The signal was received at 10:38 CET on April 8, 2026, and verified by ESA teams at ESTEC as well as at GMV’s monitoring station in Lisbon.

The milestone marks successful commissioning of the spacecraft and opens the operational experimentation phase of a program designed to test whether a complementary low Earth orbit navigation layer can enhance Galileo’s accuracy, resilience, and security. Celeste IOD-1 and a second demonstrator, IOD-2, were launched March 28 aboard a Rocket Lab vehicle from Launch Complex 1 in Mahia, New Zealand. The two satellites — built by separate European consortia, with GMV leading one and Thales Alenia Space the other — separated from the launch vehicle approximately one hour after liftoff. LEOP and commissioning activities for IOD-1 were conducted by an integrated GMV and Alén Space team from the mission control center in Tres Cantos.

Operating at altitudes between 500 and 560 km, the demonstrators will validate precise autonomous orbit determination without ground infrastructure dependence and will test navigation signal performance in L- and S-bands from LEO. The program’s rationale is multi-orbit resilience: by integrating a LEO constellation alongside Galileo’s medium Earth orbit architecture, Celeste aims to reduce vulnerability to interference and expand the envelope of advanced PNT services available to European users.

The IOD phase will comprise eleven satellites plus one in-orbit spare across both consortia. GMV holds prime contractor responsibility for six of the demonstrator satellites, covering system definition and design, space and ground segments, user segment, and operations. The two initial demonstrators are focused on securing registered frequency allocations and signal testing through the end of 2025. Eight larger follow-on satellites are under development, with subsequent launches targeting 2027 and the eventual fielding of a full operational fleet.

GMV was selected by ESA in 2024 to lead one of the two parallel Celeste development contracts.

The post GMV’s Celeste IOD-1 Transmits First Navigation Signal from LEO appeared first on Inside GNSS - Global Navigation Satellite Systems Engineering, Policy, and Design.

GABRIEL THYS SAFRAN ELECTRONICS & DEFENSE, AND FÉDÉRATION ENAC ISAE-SUPAERO ONERA, UNIVERSITÉ DE TOULOUSE; CHRISTOPHE MACABIAU, JULIEN LESOUPLE, JÉRÉMY VÉZINET, ANAÏS MARTINEAU FÉDÉRATION ENAC ISAE-SUPAERO ONERA, UNIVERSITÉ DE TOULOUSE; RAPHAEL JARRAUD

The approach phase is one of the most safety-critical segments of a civil aircraft flight. Within the framework of Performance-Based Navigation (PBN), navigation systems must satisfy strict requirements in terms of accuracy, availability, continuity and integrity [1]. These constraints become particularly stringent during the final segment of a precision approach, which extends from the Final Approach Point, approximately 7 nautical miles from the runway threshold, down to the decision altitude [2].

Aircraft guidance during this phase traditionally relies on the Instrument Landing System (ILS) or on Global Navigation Satellite Systems (GNSS) augmented by space-based (SBAS) or ground-based (GBAS) augmentation systems [2]. However, conventional radionavigation infrastructures are progressively being reduced to a Minimum Operational Network intended to mitigate large-scale GNSS outages [3]. As a result, modern precision approaches increasingly depend on augmented GNSS solutions. In practice, the radio-frequency environment around airports may be affected by Radio Frequency Interference (RFI), which can degrade or interrupt GNSS signals. Such disruptions may force aircraft to interrupt the approach and revert to the remaining conventional navigation aids. Ensuring operational continuity, therefore, requires complementary sensors that are passive and robust to RF disturbances.

Optical sensors constitute promising candidates, particularly during the approach phase when the aircraft operates close to the ground and the visual environment provides rich navigation data. Although commercial aircraft are already equipped with onboard cameras to enhance pilot situational awareness during approach, landing and taxiing, these sensors rarely provide operational credit, and their potential remains largely underexploited.

Vision-based navigation relative to the runway has attracted increasing research interest. The European Japanese VISION project developed a hybrid inertial-GNSS-vision navigation system based on an error-state Kalman filter accounting for image processing delays [4]. The C2Land project, led by the Institute of Flight Guidance at Technische Universität Braunschweig, investigates autonomous landing at airports without ground infrastructure by fusing optical and inertial data with non-augmented GNSS [5]. Flight experiments conducted within this project represent some of the most advanced demonstrations of vision-based navigation systems.

Despite these developments, integrating cameras into safety-critical navigation architectures raises important integrity challenges. Vision sensors introduce new failure modes that must be incorporated into the integrity monitoring framework with appropriate risk allocation. However, integrity monitoring methods for vision-based navigation remain relatively limited. Many approaches adapt algorithms originally designed for GNSS, such as RAIM-based techniques using synthetic measurements derived from visual landmarks or batch implementations [6,7] or extensions of AIME using multiple optical sensors [8]. More recent work proposed protection level formulations for hybrid inertial-vision-GNSS systems considering multiple fault modes [9].

However, as highlighted in the survey by [10], the direct application of GNSS integrity methods to vision measurements is generally suboptimal due to the specific characteristics of optical observations and the limited availability of statistical models describing their integrity behavior. This lack of operational experience complicates compliance with the stringent integrity requirements of civil aviation precision approaches as it requires conservative assumptions.

This study builds upon the hybrid inertial-vision-GNSS system introduced by [11], which is designed to ultimately comply with the performance requirements of a PBN CAT I precision approach. It aims to characterize the impact of vision integration on continuity and integrity requirements and to derive false alarm and missed detection probabilities that an integrity monitoring algorithm must verify.

Navigation Dual Navigation System Design

Navigation System Assumptions

The navigation system considered in this article is designed to support PBN CAT I precision approach operations. The system is set in the context of a radio frequency environment potentially disturbed by jamming or spoofing, resulting in potential GNSS service loss of continuity or unavailability. In the PBN framework, any such GNSS event during a precision approach would trigger a navigation system alert, requiring the pilot to initiate a missed approach procedure [1]. 

The hybrid navigation system integrates measurements from four distinct sensors, including

• A navigation-grade inertial measurement unit (IMU) providing high-quality angular and velocity increments

• A GNSS receiver processing satellite signals (Signal-In-Space) and SBAS corrections to compute a 3D position

• A barometric altimeter used to stabilize the IMU’s vertical channel, supplying altitude information

• A vision system composed of one or more imaging sensors (e.g., monocular, stereo, infrared) and an image processing unit. 

The selected vision-based navigation approach relies on landmark-based positioning [12]. The optical sensors observe the aircraft’s environment, referred to as the scene, and specifically detect the runway, from which one or more landmarks are extracted. The 3D positions of these landmarks are supposed to be a priori known and retrieved from the Aeronautical Information Publication (AIP). By associating each landmark with its known coordinates, a line-of-sight vector between the camera and the landmark can be reconstructed. This line-of-sight serves as the vision measurement input to the estimation process. A tightly coupled integration scheme is hence considered in this architecture. The data fusion and state estimation process is based on an error-state Kalman filter [13]. The filter’s structure, along with the mathematical modeling of its propagation and measurement equations, are detailed by [11].

The hybrid navigation system provides guidance system estimates of key navigation parameters, including position, velocity and attitude. It is also designed to provide integrity monitoring and issue alerts in the event of a continuity loss. In parallel, a predefined flight path is derived from a waypoint database and provided to aircraft guidance. This guidance is ultimately used by the flight crew.

Single-Filter Architecture Limitations

A straightforward extension of an SBAS-augmented inertial-GNSS navigation system consists of integrating vision measurements within a triple inertial-GNSS-vision hybrid architecture. Such integration can significantly improve continuity of service because vision measurements can compensate for temporary GNSS outages. In this configuration, a loss of continuity would only occur if both GNSS and vision measurements become unavailable simultaneously. This capability is particularly valuable given the increasing vulnerability of GNSS to RFI.

However, the introduction of vision also brings additional failure modes that must be considered in the integrity risk allocation. When these failure modes are incorporated into the integrity framework, they may inadvertently tighten the integrity requirements associated with the SBAS-augmented GNSS subsystem. Consequently, improving continuity through sensor redundancy does not automatically translate into improved system integrity and may even degrade it if failure dependencies are not properly managed. The limitations of such triple-hybrid architectures are discussed in [14]. 

The integration of vision into an inertial-GNSS hybrid navigation system introduces a fundamental technical challenge arising from two partially conflicting objectives: 

• To increase the continuity of service by leveraging vision measurements to bridge potential GNSS service losses

• To ensure this integration does not increase the integrity requirements allocated to the SBAS-augmented GNSS system.

Technical Solution: Dual Navigation Architecture

To resolve this trade-off, this work proposes a dual-navigation architecture in which vision measurements are integrated without increasing the integrity constraints imposed on the GNSS subsystem. The core principle of this architecture lies in the implementation of two parallel navigation solutions. 

The first, referred to as the Main Navigation, relies solely on measurements from the GNSS, the navigation-grade IMU and the barometric altimeter, deliberately excluding any vision data. As such, this navigation chain corresponds to a state-of-the-art SBAS-augmented inertial-GNSS navigation system. 

In contrast, the second solution, referred to as the Vision Navigation, uses only the IMU, barometric altimeter and vision-based measurements, excluding any GNSS inputs. It thus forms a pure inertial-vision navigation system. 

During a precision approach conducted by a civil aircraft, the navigation outputs, comprising the estimated navigation states (position, velocity and attitude) as well as the associated integrity monitoring functions and alerts, are provided by either the Main Navigation or the Vision Navigation subsystem. By default, the system delivers navigation outputs from the Main Navigation as long as the SBAS-augmented GNSS service is available. When the GNSS service becomes unavailable and is formally declared out of service, the navigation outputs are transferred to those generated by the Vision Navigation. This transition is handled by a dedicated switching mechanism whose operation is governed by the availability status of the augmented GNSS service. 

The use of two parallel navigation solutions, therefore, enable a clear separation of integrity risks associated with GNSS and vision within their respective navigation chains. The resulting dual-navigation configuration is illustrated in Figure 1. 

The proposed architecture benefits from the well-established performance of the inertial-GNSS hybrid system as long as GNSS signals are available, thereby maintaining the integrity of a navigation solution that has already been extensively validated. At the same time, it ensures continuity of service in the event of a GNSS outage by incorporating vision-based measurements into the overall navigation process. From the user’s perspective, the system continues to provide the required navigation information without indicating whether it originates from the main or vision-based navigation branch. 

Starting Point of the Study

Assumptions and Definitions 

Integrity and continuity allocations for the hybrid navigation system are analyzed using fault/risk allocation trees that describe the logical relationships between failure modes and their causes. The interpretation and computation rules of these trees are defined in [2]. 

Integrity represents the level of trust in the correctness of the navigation information and includes the system’s ability to provide timely alerts [2]. An integrity failure occurs when the Navigation System Error (NSE) exceeds the horizontal or vertical alert limits, producing a Hazardous Misleading Information (HMI) event. This event can be expressed as [17]:

where e denotes navigation error, AL the operational alert limit, y the vector of measurements and Ω the set of measurements considered consistent with the integrity monitor. The integrity risk corresponds to the probability that this event occurs without triggering an alert within the specified time-to-alert [2].

Continuity refers to the system’s ability to perform its function without interruption, assuming it is available at the beginning of the operation. Although a precision approach typically lasts about 150 seconds, the continuity risk defined in [2] only concerns the final 15 seconds of the approach. Continuity loss events include integrity monitor alerts, unscheduled GNSS outages, and RFI disturbances. From a fault detection perspective, these events are primarily driven by detection alarms, which are generally dominated by false alarms. GNSS outages occurring earlier in the approach are instead classified as losses of availability.

Risk Allocation for a SBAS Augmented Inertial-GNSS Navigation System

To derive the fault allocation tree for the proposed hybrid navigation system, a reference allocation model is first established based on an SBAS-augmented inertial-GNSS architecture. The resulting structure, illustrated in Figure 2, follows the fault allocation framework developed for SBAS-based APV and CAT I approaches by [15].

The top-level metric is the Target Level of Safety (TLS), defined as the acceptable hull-loss probability per aircraft per flight hour. For approach operations, the TLS is 1×10^-8 per approach, assuming a standardized duration of 150 seconds. Considering one catastrophic accident is associated with approximately 10 incidents, the associated risk budget becomes 1×10^-7, which is equally allocated to continuity and integrity branches.

To derive system-level requirements, an additional breakdown is required. This refinement incorporates the mitigating influence of the flight crew. Operational analyses indicate reduction factors of seven for integrity and 2,000 for continuity, reflecting the fact continuity losses occurring during the final seconds of an approach can often be managed visually, whereas integrity failures may generate misleading guidance.

After applying these factors, the navigation system requirements for PBN CAT I approaches are 1×10^-4 for continuity and 3.5×10^-7 for integrity per approach.

These requirements are allocated between aircraft and non-aircraft subsystems.

• Aircraft subsystems include all onboard navigation components, such as the GNSS receiver hardware, timing modules and processing software. Failures originate from internal causes (hardware faults, power interruptions, interface failures). Compliance with the continuity and integrity requirements is the responsibility of the aircraft manufacturer or avionics supplier, who must demonstrate their equipment satisfies the allocated risk budgets. In certification, continuity compliance is commonly shown using Mean Time Between Failure (MTBF) analysis, whereas the integrity requirement may be validated through design assurance processes and fault detection mechanisms as defined by applicable certification standards.

• Non-Aircraft subsystems correspond to external contributors affecting navigation performance. In an SBAS-augmented architecture, this branch is limited to SIS, including GNSS signals and SBAS corrections. The navigation system must, therefore, ensure compliance with these requirements through appropriate integrity monitoring. Because these non-aircraft requirements relate solely to the external environment, the on-board equipment, specifically the GNSS receiver, are assumed to be ideal (or fault-free), i.e., operating nominally without introducing failures within the measurements. Under this assumption, responsibility for meeting the allocated performance requirements resides with the on-board navigation system, specifically through its integrity monitoring algorithms. Consequently, the non-aircraft continuity and integrity requirements define the performance thresholds the navigation system must meet.

Continuity Requirements for the Vision-Integrated Navigation System

Following the same methodology, the vision subsystem is decomposed into aircraft and non-aircraft branches to clearly delineate responsibility boundaries. This classification enables the identification of risks that fall under the scope of the aircraft manufacturer versus those that must be addressed by the on-board navigation monitoring functions.

Vision Aircraft Loss of Continuity 

Aircraft continuity risks originate from failures of onboard hardware or software involved in the vision processing chain. Vision measurements are produced through two main stages: image acquisition by optical sensors and landmark detection using onboard image-processing algorithms.

Failures affecting either stage may interrupt the generation of vision measurements. Optical sensors can be affected by hardware faults such as lens contamination, power interruption or optical degradation, while the processing chain may suffer from processor failures or software crashes. In this study, an aircraft-level continuity loss is defined as any failure of the onboard vision subsystem to produce a runway landmark measurement, assuming the scene observability allows it.

The continuity requirement allocated to the vision function is 10^-1 per approach. This relatively relaxed constraint reflects common image degradation mechanisms such as lens contamination or water droplets. Compliance is verified through equipment reliability analysis (e.g., MTBF), and redundancy such as sensor triplication can be used to improve overall continuity performance.

Vision Non-Aircraft Loss of Continuity 

Non-aircraft continuity risks correspond to environmental effects that degrade vision measurements while the onboard equipment operates nominally. In this context, the vision subsystem is assumed to produce at least one valid measurement. Under this assumption, continuity loss may occur when the navigation system monitoring declares an alarm, for instance when protection levels exceed the alert limits or when a measurement anomaly cannot be excluded.

For GNSS, environmental disturbances are captured within the SIS concept. In vision-based navigation, the equivalent disturbances arise from the optical environment, which affects the propagation of visible or infrared radiation between the runway and the camera. Environmental perturbations increasing measurement noise are generally referred to as photometric noise, and include poor illumination conditions or strong reflections from the runway surface. These effects increase measurement variance and protection levels, whereas large biases or outliers are addressed within the integrity monitoring framework.

For the hybrid navigation system, the non-aircraft continuity risk is allocated to 8×10^-5 per approach. 

Weather Impact

Operational conditions may prevent the vision subsystem from producing any measurement, for instance during night operations with visible-spectrum cameras or under adverse meteorological conditions. Such situations must be explicitly considered in the continuity allocation.

In this study, meteorological conditions preventing vision measurements are classified as non-aircraft continuity risks, as they originate from the external sensing environment rather than from failures of the onboard equipment. This treatment is consistent with the modeling of GNSS outages caused by radio frequency disturbances.

Two modeling strategies can be considered. One approach assumes complete vision unavailability due to environmental conditions is negligible compared to continuity losses caused by monitoring false alarms. However, this assumption is unrealistic because no existing optical system can guarantee a negligible probability of total vision unavailability.

The adopted approach, therefore, explicitly accounts for weather effects by decomposing the vision observation continuity risk into two contributions:

• Losses caused by adverse meteorological conditions, and

• Losses caused by false alarms of the fault detection function.

Assuming one approach out of 20 is affected by weather conditions preventing optical measurements, the resulting continuity risk associated with vision observation is 3×10^-2 per approach. For a fault detection rate of 1 Hz, this corresponds to a false alarm probability of

Continuity Risk Allocation Tree

The introduction of vision into an inertial-GNSS navigation architecture affects both aircraft level equipment continuity risks and non-aircraft continuity risks driven by the external environment. The corresponding allocation tree is illustrated in Figure 3. In this representation, scene observation is explicitly placed within the non-aircraft domain, as it inherently accounts for environmental effects, including meteorological conditions. The aircraft-level vision function is represented by its two main components: the optical sensors and the image-processing unit. 

The introduction of vision-based navigation substantially alleviates the continuity requirements previously imposed on the GNSS Signal-in-Space. In both aircraft and non-aircraft contexts, continuity loss occurs only when vision and GNSS are simultaneously unavailable. This architectural change yields multiple benefits. First, it relaxes equipment-level continuity requirements, which is advantageous for both aircraft manufacturers and equipment suppliers. Second, it explicitly addresses the growing risk of radio frequency interference, as the continuity risk allocated to the GNSS SIS is reduced by a factor of 12.5, down to 1×10^-3 per approach.

Integrity Requirements for Vision-Integrated Navigation 

Vision Aircraft Loss of Integrity

Quantifying the integrity associated with airborne vision equipment is challenging. Integrity failures associated with airborne vision equipment occur when erroneous measurements produced by the onboard vision subsystem are accepted as valid by the navigation system and lead to navigation errors exceeding the alert limits. As with continuity risks, compliance with integrity requirements is primarily ensured through equipment certification.

Aircraft-level integrity threats originate from two components of the vision subsystem:

• Optical sensors may experience hardware failures such as calibration errors, lens defects, geometric distortions, or failures of the imaging elements.

• Image processing failures arise from abnormal behavior of the onboard processing chain, including feature detection errors, computing faults, radiation-induced bit errors, or errors in optical multi-sensor fusion. Because the integrity risks considered in the aircraft domain are related to equipment failures rather than external environmental conditions, a core assumption is adopted: In the absence of sensor or processing failures, the produced measurement would be correct.

Failures affecting optical sensors can reasonably be considered random and statistically independent, i.e., not subject to common-mode effects. Under this assumption, and in addition to integrity loss rates guaranteed by the manufacturer through certification processes, these integrity risks can be mitigated through a combination of equipment redundancy, and internal fault detection mechanisms within the processing chain. 

These mitigation strategies may reduce the integrity loss probability associated with airborne vision equipment to levels that are either negligible (≈10^-9 per approach) or sufficiently small to remain within the aircraft-level integrity allocation already assigned to the inertial-GNSS navigation system (10^-7 per approach). Whether a specific allocation should be explicitly assigned to vision equipment remains open to interpretation. Regardless of the chosen allocation strategy, the validation and certification of vision equipment integrity remain the responsibility of the equipment manufacturer, as these failure modes are not monitored by the fault detection mechanisms implemented at the navigation system level.

Vision Aircraft Loss of Integrity 

A non-aircraft integrity failure occurs when a vision measurement is corrupted by abnormal errors induced by the external environment. In contrast with continuity analysis, measurement availability is assumed, and environmental effects are considered only through their impact on measurement quality.

The visual environment along the line of sight between the runway and the onboard camera plays a central role. Measurement errors generally consist of two components:

• Photometric noise, representing the nominal stochastic error of the measurement, and

• Deterministic biases, corresponding to abnormal measurement errors.

Photometric noise arises from variations in illumination conditions or scene characteristics, such as overexposure, motion blur, atmospheric disturbances, or runway reflections. Although these effects may increase measurement variance and degrade navigation accuracy, they are treated as nominal realizations within the measurement noise model. The corresponding feared event arises when the photometric noise magnitude becomes abnormally large, corresponding to extreme realizations in the tails of the assumed Gaussian distribution. Although such events may significantly affect navigation accuracy, they are considered as rare normal performance under fault-free conditions, as no underlying abnormal failure or bias is present.

Integrity-threatening events correspond to deterministic biases affecting the estimated line of sight between the landmark and the camera. Two main sources of such biases are identified:

• Incorrect feature detection, where the selected landmark does not belong to the intended runway.

• Incorrect landmark association with the corresponding three-dimensional reference coordinates.

Preliminary studies have proposed models for nominal measurement errors [16] and landmark association failures [12]. However, these results remain limited to specific scenarios and do not yet satisfy the stringent integrity requirements of civil aviation. Consequently, conservative assumptions are typically adopted when modeling vision-based integrity risks.

On-Board Monitoring Assumptions

The use of two parallel navigation solutions enables a clear dissociation between integrity risks associated with GNSS and those associated with vision-based navigation. Depending on which navigation branch is active, Main Navigation or Vision Navigation, the set of measurements used to compute the navigation solution differs. As a result, the corresponding failure events, namely GNSS SIS failure and vision observation failure, are mutually exclusive and cannot be jointly considered within a single integrity allocation tree. Each navigation solution is therefore characterized by its own failure modes, its own fault tree, and a dedicated integrity monitoring strategy.

Given that it is not possible to determine with certainty in advance which of the two navigation solutions will be active during a given approach, a conservative assumption is adopted. Accordingly, the full integrity risk associated with the on-board navigation system monitoring, equal to 2×10^-7 per approach, is allocated to each navigation solution without assuming any prior knowledge of the active one.

Main Navigation Integrity Risk Allocation

For the Main Navigation, because it corresponds to a state-of-the-art inertial-GNSS system augmented by SBAS, the sole failure mode to be considered is the SIS failure. The associated integrity monitoring is based on two hypotheses when this navigation branch is active:

H₀ Fault-Free: An HMI event may arise due to excessive measurement noise on the pseudo range observations.

H₁: Signal-In-Space Failure: One or more satellite measurements are faulty, or the ground segment is corrupted.

The total integrity risk allocated to the navigation system (2×10^-7 per approach) is therefore distributed equally between the two navigation hypotheses of the Main Navigation. The integrity of this navigation configuration is well established in the literature. In particular, the integrity risk allocation tree proposed by [15] can be directly applied, together with standard GNSS integrity monitoring techniques. As a result, the dual-navigation architecture avoids imposing additional integrity constraints on the GNSS SIS performance.

Vision Navigation Integrity Risk Allocation

In the case of Vision Navigation, only one failure mode is considered: Vision Observation Failure mode. When this navigation is active, integrity monitoring is based on two hypotheses:

H₀ Fault-Free: An HMI event may result from excessive photometric noise induced by the observed scene. 

H₁ Vision Observation Failure: A measurement bias affects one or more visual landmarks.

The entire integrity risk of the navigation system (2×10^-7 per approach) is distributed between the fault free and faulty vision hypotheses based on an arbitrary allocation. In this study, the integrity risk associated with the fault-free hypothesis is set to 4×10^-8 per approach, while the risk allocated to the Vision Observation Failure mode is set to 1.6×10^-8 per approach.

Probability of Missed Detection 

Based on the proposed allocations, it is possible to derive the missed detection probability required for a fault detection algorithm applied to vision measurements, defined as 

Assuming the correlation time of a vision failure and its associated integrity loss extend over the entire approach duration, the required missed detection probability is given by [14]

where IR_req denotes the integrity requirement associated with a vision observation failure, and R(H₁) represents the occurrence rate of vision observation failures. 

This expression highlights that the missed detection probability is inherently linked to the occurrence rate of vision observation failures. However, accurately quantifying this rate remains challenging. Unlike GNSS, vision-based sensors do not benefit from several decades of operational experience and extensive user feedback, particularly in the aeronautical domain. To mitigate this uncertainty, internal consistency checks within the vision processing pipeline, such as image filtering, plausibility tests, or redundancy-based consistency checks, may be implemented to reduce the effective vision failure rate. In addition, the use of external position estimates can constrain the search area for the runway within the image, thereby improving robustness.

A failure probability of 10^-4 for vision-based observations has been suggested in [9]. Assuming a correlation time equal to the approach duration, this corresponds to a failure rate of 10^-4 per approach. In this study, a slightly more conservative value of 1.6 ×10^-4 per approach is adopted, leading to a maximum allowable missed detection probability of

Dual-Navigation Integrity Risk Tree

The modified integrity allocation tree for the dual-navigation system is shown in Figure 4. The non-aircraft allocation consists of two separate subtrees: one for the Main Navigation and one for the Vision Navigation. The navigation system selects the relevant subtree depending on the active navigation mode. This behavior is represented by a switching element at the top level of the integrity allocation tree. Consequently, the total non-aircraft integrity risk is allocated independently to each navigation branch.

Conclusion

This study investigated the role of vision-based measurements in improving the continuity of navigation services for civil aircraft during precision approach operations. A continuity risk allocation tree was developed to analyze the contribution of vision sensors while distinguishing between aircraft-level equipment failures and observation failures at the navigation system level.

To accommodate the specific characteristics of vision measurements, a dual-navigation architecture was proposed. In this architecture, the navigation system operates with an SBAS-augmented inertial-GNSS solution when GNSS signals are available and transitions to an inertial-vision solution when GNSS is declared unavailable. This design enables the separation of GNSS and vision constraints and leads to the definition of two independent integrity allocation trees corresponding to the two navigation modes.

The proposed framework contributes to the design of resilient navigation architectures capable of maintaining navigation service during GNSS outages. The integrity constraints associated with the vision-based navigation mode were analyzed, and the corresponding false alarm and missed detection probability requirements were derived. These results provide key guidelines for developing dedicated fault detection and integrity monitoring algorithms for vision-based navigation systems intended for safety-critical aviation applications. 

Acknowledgements 

This article is based on material presented in a technical paper at ION GNSS+ 2025, available at ion.org/publications/order-publications.cfm.

References 

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(9) H. Jiang, T. Li, D. Song and C. Shi, “An effective integrity monitoring scheme for gnss/ins/vision integration based on error state ekf model,” IEEE Sensors Journal, pp. 7063–7073, 2022. 

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Authors

Gabriel Thys is a Ph.D. candidate at Safran Electronics & Defense in collaboration with ENAC. His research focuses on GNSS, vision-based navigation, inertial systems, multi-sensor fusion, and integrity monitoring algorithms. He obtained a M.Eng. degree in space telecommunications from ENAC . He works as a system engineer in signal processing for high-performance aeronautical navigation systems at Safran Electronics & Defense.

Christophe Macabiau graduated as an electronics engineer in 1992 from the ENAC. Since 1994, he has worked on the application of satellite navigation techniques to civil aviation. He received his Ph.D. in 1997 and has been in charge of the signal processing lab of ENAC since 2000. He is the head of the TELECOM research team of ENAC that includes various research groups.

Raphael Jarraud is a senior expert in inertial navigation and sensor fusions, working for Safran Electronics & Defense. He has 22 years of experience in designing, simulating and testing inertial navigation systems. He graduated from CentraleSupelec in 2003, with a major in control systems.

Julien Lesouple received the Eng. degree in Aeronautics Engineering from ISAE Ensica, Toulouse, France in 2014 and his Ph.D. in Signal Processing from Toulouse Institut National Polytechnique in 2019. Since 2021, he has worked as an Associate Professor at ENAC within the SIGNAV team. His research interests include statistical signal processing, machine learning, estimation and detection theory, filtering, with applications to satellite communications, localization, tracking, navigation, and anomaly detection.

Jérémy Vézinet graduated as an electronics engineer in 2010 and obtained his Ph.D. in 2014 on multi-sensor hybridization from ENAC. He has worked as a Research Associate in the TELECOM Research Team at ENAC since 2014. His interests are GNSS, INS, video-based navigation, multi-sensor hybridization and integrity monitoring.

Anaïs Martineau graduated in 2005 as an electronics engineer from the ENAC. Since 2005, she has worked at the signal processing lab of the ENAC, where she carries out research on integrity monitoring techniques. She received her Ph.D. from the Université de Toulouse. She is the head of Electronics, Electromagnetism and Signal Processing Division and ENAC Engineers and GNSS Master’s Course Director.

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GOSAS: From Accidental Discovery to Dedicated Mission

The GNSS Orbiting Situational Awareness Sensor, or GOSAS, is a CubeSat-compatible, programmable dual GPS receiver that will operate from orbit to monitor conditions affecting space-based GNSS signals. “Understanding and predicting space weather is critical for ensuring the accuracy of GPS and the integrity of military communications,” said Scott Budzien, NRL research physicist and GOSAS principal investigator.

GOSAS is a direct follow-on to NRL’s GROUP-C experiment, which operated aboard the International Space Station from 2017 to 2023. GROUP-C’s primary mission was GPS radio occultation and ultraviolet photometry, but the experiment serendipitously detected GPS ground interference from orbit — a finding with significant implications for counterspace situational awareness. GOSAS was conceived in 2020 specifically to build on that capability, formalizing orbital GNSS environment characterization as a dedicated mission objective rather than an incidental one. The timing is notable: as documented in assessments including the Secure World Foundation’s newly released Global Counterspace Capabilities 2026, GPS jamming over conflict zones has now been shown to affect LEO satellites carrying onboard GPS receivers, creating measurable gaps in orbital PNT coverage. A purpose-built sensor for detecting and characterizing that interference environment addresses a documented and growing operational gap.

The STPSat-7 spacecraft launched at approximately 4:33 a.m. PDT from Vandenberg Space Force Base, California, aboard a Northrop Grumman Minotaur IV launch vehicle as part of the STP-S29A mission.

Companion Payloads Address Debris and Radiation Detection

The two additional NRL payloads round out a broad space environment characterization effort. LARADO — the Lasersheet Anomaly Resolution and Debris Observation instrument — will detect and characterize small orbital debris that cannot be tracked from the ground, providing data to update debris models used by spacecraft engineers, satellite operators, and policymakers. The LARADO concept dates to 2012 and has been funded since FY22 through NASA’s Heliophysics Division. GARI-1C, the third payload, will space-qualify new gamma-ray detector technology using commercial off-the-shelf components, with an eye toward future defense applications including detection of weapons of mass destruction from orbit.

The Space Test Program, operating under U.S. Space Systems Command, was established in 1966 to provide flight opportunities for research and development payloads with potential military utility. “The success of this mission highlights how cutting-edge research and development are fundamental to preserving America’s strategic edge in space,” said USSF Lt. Col. Brian Shimek, system program manager and director for STP.

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Institutional Escalation: ICAO and ITU Act

The most significant development for the GNSS community may be regulatory rather than technical. In October 2025, the International Civil Aviation Organization passed a resolution condemning GNSS interference originating from both Russia and North Korea as violations of the 1944 Convention on International Civil Aviation. The following month, the ITU’s Radio Regulations Board, at its 100th meeting, again urged Russia to “immediately cease any source of harmful interference” to safety services in the Radio Navigation Satellite Service — specifically interference affecting receivers in Estonia, Finland, Latvia, and Lithuania originating from Russian territory.

The Baltic situation had intensified steadily through the year. Lithuania coordinated a letter signed by 17 EU transport and digital ministers in June 2025 calling for a coordinated European Commission response. The European Council’s own data showed aircraft GNSS interference cases in Poland rising from 1,908 in October 2024 to 2,732 by January 2025. Estonia announced in July 2025 that Russia had moved jamming equipment to a site at Kingissepp, 20 kilometers from its border, and reported that GPS jamming had caused over €500,000 in damage in the preceding three months alone. Sweden’s Department of Transport stated that interference over the Baltic was occurring “almost daily” and had spread “both geographically and in scope.”

Active Conflict: Iran, India-Pakistan, Israel

The SWF report also documents the operational deployment of GNSS interference in three distinct conflict contexts in 2025.

During Iran’s 12-day war with Israel in June 2025, Iran jammed GPS over multiple metropolitan areas to counter drone and missile threats. Iran’s Deputy Communications Minister publicly acknowledged the disruptions were “for military and security purposes.” The Maritime Information Cooperation and Awareness Center estimated that 970 ships per day experienced GPS jamming in the Strait of Hormuz during this period, causing traffic through the Strait to drop by 20 percent as vessels limited transits to daylight hours. The report adds a technically notable January 2026 data point: during protests in Iran, Starlink ground terminals were found to have had their GPS units spoofed, causing packet losses of 30 to 80 percent. Users who switched to Starlink’s internal position estimates restored connectivity; SpaceX subsequently pushed a software update to mitigate the interference.

In South Asia, during India’s Operation Sindoor against Pakistan in May 2025, Indian electronic warfare forces were deployed specifically to interfere with GNSS signals to hamper Pakistani military aircraft navigation. The report notes that GPS spoofing has since migrated from the border zone into civilian airspace: more than 10 percent of flights in the Delhi region have reported spoofing incidents, and in November 2025 interference around Indira Gandhi International Airport was severe enough to divert flights to alternate airports.

Israel, for its part, entered into a formal commitment at the ITU in late 2025 to limit RNSS-interfering transmissions to situations involving imminent threats to life or critical infrastructure, capped at 15 minutes per incident — following a July 2025 meeting with Jordan and Egypt convened under ITU auspices.

The LEO Dimension

Perhaps the most technically striking finding for GNSS engineers: the report cites Aerospace Corporation research from July 2025 indicating that GPS jamming over Ukraine has created what researchers described as “a giant hole” in GPS coverage for small LEO satellites carrying onboard GPS receivers for position, navigation, and timing. The jamming environment over a conflict zone is now affecting space-segment PNT — not just ground users.

The Secure World Foundation’s Global Counterspace Capabilities 2026 is available here.

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While GNSS remains the backbone of positioning, its limitations can’t be ignored. GNSS signals are vulnerable to multipath interference, while spoofing and jamming attacks that render GNSS unreliable continue to grow in number and sophistication. Urban canyons, tunnels and indoor transitions also remain a challenge for GNSS and the users who require access to accurate positioning in these environments.

This reality, combined with the rise in autonomous solutions across various industries from agriculture to defense, makes closing the growing gaps in GNSS mission critical. Reliable, backup 
solutions are a must. Inertial navigation systems (INS) are a natural complement, providing continuous, high-rate propagation through GNSS outages. 

The push for autonomy has ushered in a new era of GNSS-INS integration, making this combined approach mainstream rather than exotic. Inside GNSS, along with Hexagon | NovAtel and Inertial Sense, explored this critical integration in a recent webinar. James Chan, business unit lead, INS, Aerospace & Defence Division, Hexagon, provided the system-level perspective, while Walt Johnson, founder and CTO of Inertial Sense, focused on low-SWaP-C tactical grade MEMS implementation.

IMU Fundamentals and the Cost–Accuracy Ladder

Chan gave us a look inside what makes up inertial measurement units (IMUs), the core of an INS. IMUs come in different options and grades, but all 
leverage various sensors to measure an object’s movement and orientation. Accelerometers measure linear acceleration, while gyroscopes measure rotational acceleration. Both typically operate on three axes, giving the IMU six degrees of freedom (DoF).

Many IMUs now also include magnetometers to measure magnetic fields, which can be translated into a heading, Chan said, and barometers to measure atmospheric pressure, which can be translated into an altitude. IMUs that include a three axis magnetometer have 9 DoF, while those that also have a barometer achieve 10 DoF. Magnetometers typically require calibration to account for local interference and magnetic declination. 

It’s important to note that every IMU has drift, Chan said, which leads to accumulating errors in the IMU data. These errors will continue to grow if there’s no external input to correct them. The drift rate is also dependent on sensor stability. 

“Nearly all inertial navigation systems will run some kind of filter, usually an Extended Kalman Filter or EKF, and that’ll have the INS solution running and take in GNSS updates to help compensate for any errors in the IMU measurements,” Chan said. “In between updates, the inertial solution will bridge the gap and continue to offer position, velocity and attitude at times when GNSS isn’t available.” 

An IMU’s accuracy, Chan said, is driven by the gyroscope, with three main types available: Ring laser gyroscope (RLG), fiber optic (FOG) gyroscope and Microelectromechanical Systems (MEMS). The RLG, the oldest, features two counter-propogating lasers that travel within a closed space, using a system of mirrors to “effectively bounce those lasers.” When the system rotates, one beam travels a longer path than the other. The detector picks that up and calculates the rotation rate based on the time difference of when the two lasers arrive. 

The newer FOGs also measure two beams of light, but do so by traveling around a closed fiber optic coil and measuring the difference of when the beams arrive back. Increasing the coil length changes the resolution on what a FOG can measure. 

FOGs tend to be smaller and cheaper than RLGs, but typically aren’t as accurate, Chan said, though the technology continues to improve. 

These days, most people use MEMS gyroscopes. There’s different types of MEMS for various applications, but all basically look at how a silicon structure behaves after some sort of force is applied. Compact MEMS gyroscopes have the lowest SWaP-C and can be found on anything from cell phones to UAS. 

Regardless of type, IMUs come in different classification grades: consumer, industrial, tactical and navigation. Gyro in-run bias stability is how a gyroscope bias drifts over time during operation at a given temperature. It is also referred to as bias instability. The higher the value, the more unstable the bias drift will be, and the worse the results you’ll get. 

Angular Random Walk (ARW) is another key metric, measuring the signal noise to indicate what the angular error could look like as it accumulates over time. 

“These values are determined by doing an Allan Variance Plot, and it’s a critical metric for determining gyroscope accuracy,” Chan said. “Smaller values indicate the random noise associated with the signal will have less of an impact on your angular measurements.” 

Quantum IMUs are also on the horizon, Chan said. These next generation navigation sensors will use atom interferometry to measure acceleration and rotation, measuring how lasers interact with cooled down atoms. 

“These sensors can be nearly 1,000 times as accurate as standard MEMS sensors,” Chan said, “but it’s currently limited by a low output rate and a very high power draw with no real commercial products yet.”

From Satellite Fixes to Continuous Navigation

GNSS requires visibility of the sky, with accuracy dependent on the satellites’ track, Chan said, one of its limitations. Still, there is “no better system to provide an absolute position that has zero infrastructure requirements needed on the user side besides an antenna and receiver.” Tightly integrated GNSS-INS adds an important layer. GNSS is absolute but vulnerable and lower rate, while INS is relative, drifting but high-rate and immune to interference. 

Chan provided a real-world example of how IMUs make navigation more resilient, showing a NovAtel receiver moving through downtown Calgary. GNSS was pulled in multiple directions, leading to an inaccurate trajectory. When the team incorporated an IMU into the solution and ran NovAtel SPAN software, there was a “remarkable improvement” in the positioning domain due to the relative accuracy of INS while also taking in the absolute accuracy of GNSS, which helps constrain error growth.

Of course, the ranges of IMUs that can be incorporated into these systems offer varying levels of performance at different price points. There’s a fit for every application, whether mid-grade or high-grade performance is required. Key performance metrics for integrated systems include position accuracy under nominal conditions and through outages; attitude; and robustness to shock and vibration in real platforms. 

What customers are most interested in, Chan said, is position, velocity and attitude (PVA) requirements. 

“Customers will look at whether an IMU will be able to deliver in this department first,” Chan said. “On NovAtel SPAN products, we break this apart by outage duration. Customers have an easy way to understand what performance they can expect.” 

The next consideration is SWaP-C. Most want smaller IMUs that draw less power, Chan said. And as the technology matures, IMUs are naturally becoming smaller, lighter and more efficient. 

Detailed technical requirements include bias, stability, ARW and dynamic range. 

“The dynamic range for an accelerometer is measured in Gs, the gravitational unit,” Chan said. “This indicates the acceleration value the accelerometer is capable of handling and shouldn’t be confused with shock or survival ratings.” 

Then there’s velocity random walk (VRW), similar to ARW, which is a “very good indicator of how noisy the signals will be when you do integrate them.” 

There’s demand for accurate IMUs with small footprints and low weight that draw minimal power, have a wide dynamic range and a low ARW. The performance required is somewhere between industrial and tactical. 

Delivering Tactical-Grade Performance in MEMS Form Factors

Inertial Sense is focused on democratizing tactical grade GNSS-INS navigation, Johnson said, developing low SWaP-C solutions for autonomous platforms and defense applications. The company’s mission is to make effective tactical grade navigation technology accessible for platforms that are constrained by size, weight and power. 

“We deliver a multi-GNSS and MEMS IMU sensor fusion architecture that delivers tactical grade attitude, centimeter-level RTK positioning and modules that weigh less than one gram,” Johnson said. “Our systems emphasize low SWaP-C, high rate estimation and robust operation in GPS-denied environments.” 

That technology is leveraged across a range of applications, including UAS, robotic systems, maritime and precision stabilization platforms. These days, Inertial Sense is seeing increased demand driven by emerging applications like loitering munitions, engagement systems, commercial autonomous 
vehicles and humanoid robots. Such applications “require tactical grade navigation performance, but they also require mass market pricing.” Navigation grade or military grade IMUs that provide the highest performance typically cost $100,000 or more.

“The fundamental problem to the market today is tactical grade navigation systems are too expensive for large scale deployment,” Johnson said. “Our solution is to deliver industry leading navigation performance at a disruptive price performance point. This enables our customers to deploy navigation autonomy at whatever scale they require.”

The Inertial Sense product portfolio consists of compact IMX tactical grade IMUs and INS navigation modules, and the GPX series of multi-GNSS receivers. The receivers support several configurations, raw measurement output, centimeter-level positioning and dual antenna heading. Both product families are available in OEM surface modules and rugged, enclosed systems. 

Cost optimization is a key differentiator for the IMX line, Johnson said. Inertial Sense focuses on keeping tactical grade sensors to between $5,000 and $25,000, targeting low cost hardware and sensors and selecting the optimal algorithms to deliver tactical rate performance on that hardware.

“Our systems are built using off-the- shelf components,” Johnson said, “but combined with proprietary design and calibration processes that enable us to create high precision performance.”

The navigation systems also run on single precision floating point unit microcontrollers; Inertial Sense doesn’t use double precision hardware. 

“Part of what we do to maintain numerical stability is use a square root extended Kalman filter that uses UD factorization,” Johnson said. “And this approach enables stable estimation high rate updates and then efficient computation on low cost processors.” 

To maintain accuracy during high dynamic motions, Inertial Sense implemented coning and sculling compensation. The algorithm prevents systematic integration of errors, such as attitude errors caused by oscillatory rotations between gyro samples and velocity errors caused by simultaneous rotation and linear acceleration. These techniques prevent motion and oscillation vibrations from degrading the tightly integrated solution. 

Inertial Sense also offers a lightweight, multi-band RTK engine that’s optimized for low SWaP GNSS receivers and processors. A modular GNSS architecture makes it easy to integrate the IMUs with multiple receivers, including the u-blox F9 and X20. There are also plans to release firmware that supports integration with the Septentrio mosaic-G5. 

Johnson shared real-world examples of the IMU in use, with one demonstrating IMX in ground vehicle dead reckoning mode. The vehicle overcame a 105 second GNSS outage in a parking structure, driving about 350 meters and experiencing about 6% drift. In ground vehicle mode drift is “more of a function of distance traveled than time.” 

Other tests compared IMX against established systems like NovAtel SPAN, with the IMUs achieving comparable results. 

Roadmap: Pushing GNSS-INS Further for Autonomy

The latest IMX model, the IMX-6, is scheduled for release this year and represents a 30% improvement in attitude and accuracy over the IMX-5. It will support a 500 Hz output rate and will feature enhanced roll and pitch accuracy, improved heading accuracy, reduced gyro bias stability, lower ARW and lower acceleration bias instability. It also has an increased sensing range and improved sensory redundancy. 

IMX-6 will be able to handle higher acceleration ranges, with proprietary processes allowing high volume precision calibration across temperature.

As vibration performance is critical, the sensor is undergoing shock and vibration testing as well as dynamic frequency response characterization. 

“Each IMX is fully calibrated during manufacturing across a temperature range of negative 40 to 85 degrees Celsius,” Johnson said. “This includes bias calibration, cross axis alignment and scale factor calibration.” 

There are also plans to add temperature compensation for scale factor modeling.

In-field calibration procedures and guidance are also available for IMX sensors. Customers with smaller devices can place them on a precision level surface and, depending on the level of alignment needed, calibrate in a few seconds. 

“It may be that they tip it on multiple sides, or it may be that they just level it in the normal operating direction, and then they inform the system that it needs to be calibrated in what mode,” Johnson said. “There’s different modes to put it in, and it doesn’t require much space at all.”

Customers with large vehicles can use GPS to similarly inform the system of sensor alignment. Inertial Sense can guide customers through both processes. 

Enhancements to the IMX-6 allow for easier drop-in upgrades, enhanced dynamic behavior, more predictable performance across temperature, broader GNSS ecosystem coverage and smoother field maintenance for end users.

Real-World Programs and What Buyers Should Ask 

IMX sensors are making an impact across various industries. Customer case studies include: 

• A global satellite communication provider. This ongoing customer needed an INS system that could deliver a fraction of a degree of orientation accuracy for satellite tracking on moving vessels. Existing solutions were too expensive for the market they were targeting. Inertial Sense delivered a solution that integrated tactical inertial grade navigation with low SWaP GNSS receivers. They also adapted manufacturing process to support the customer’s delivery schedule. 

• A defense technology company. The unmanned systems developer needed a lower ARW and bias instability than the IMX-5 could provide. In response, Inertial Sense collaborated with the customer to develop the IMX-6, which meets both their performance and SWaP-C requirements. This opened up other opportunities with the customer. 

• An autonomous landscaping developer. This customer required high precision navigation compatible with the commercial mower equipment market. Inertial Sense worked closely with the engineering team to integrate an IMX into their autonomous platform. 

With every case study, peformance for low SWaP applications was a key consideration. Inertial Sense was able to deliver tactical-grade metrics without navigation-grade prices. The company also offers integration, support and environmental robustness. 

Before investing in a GNSS-INS solution, it’s important to know what to ask. Manufacturer data sheets differ, making it critical to understand the most important metrics and how they could impact your solution. Key areas to consider include: 

• Performance 

• Real-world testing results 

• Outage behavior 

• Calibration 

• The product roadmap and expected future updates 

GNSS-INS as Autonomy Infrastructure

Autonomy needs more than GNSS. To meet that need, GNSS-INS integration has evolved from niche, high-end avionics to a foundational technology for mainstream autonomous systems. Advances in MEMS IMUs, fusion algorithms and integration ecosystems are making tactical-grade performance accessible at scale. 

Visit insidegnss.com to access the webinar, data sheets and white papers from Hexagon | NovAtel and Inertial Sense.

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Since 2004, the primary goal of America’s national PNT policy and governance structure has been to maintain United States leadership in space-based positioning, navigation and timing (PNT). While GPS remains an outstanding system, it has been surpassed in many ways by Europe’s Galileo and China’s BeiDou.

Perhaps more significantly, while China, Russia and other nations have or are building complementary and backup systems for space-based PNT, the U.S. has no deployed capability or plans for any. This, despite a presidential mandate for such a system that stood from 2004 to 2021, and senior leaders in the current administration citing the need.

When asked why the nation has fallen behind in both space-based and alternative PNT, many experts often give a one word answer: governance. 

Governance is often defined as the process by which leaders make decisions. In the U.S., the current process for PNT was established in 2004 by President George W. Bush in National Security Presidential Directive 4. It was later slightly updated in the waning days of the first Trump administration by Space Policy Directive 7 (SPD 7), issued January 15, 2021. 

America’s PNT governance structure is complicated. One in which responsibility is shared and authority is diffuse.

A Fragmented System 

Leadership of PNT issues is assigned to two departments: The Department of Defense/War (DOD/W) for military uses and users and The Department of Transportation (DOT) for civil users.

Each department has its own internal governance processes, its own priorities, and its own bureaucratic machinery. 

Inside DOT: Many Duties, Lots of Collaboration

The DOT lead for PNT is the Assistant Secretary for Research and Technology (OST-R). But PNT is only one of many responsibilities, which also include spectrum management and overseeing the Advanced Research Projects Agency, the Bureau of Transportation Statistics, the Highly Automated Systems Safety Center of Excellence, the Intelligent Transportation Systems Joint Program Office, the Office of Research, Development & Technology, the Transportation Safety Institute, the Volpe National Transportation Center, and the Strengthening Mobility and Revolutionizing Transportation (SMART) grant program.

For PNT issues, OST-R coordinates 10 internal DOT organizations and a group of 10 organizations outside DOT. Together, these groups advise the Deputy Secretary and Secretary of Transportation.

Inside DOD/W: A Heavyweight Process with Lots of Players

On the defense side, the Chief Information Officer (CIO) is the Secretary’s principal staff assistant for PNT. But again, PNT is only one of many duties—others include information technology, cybersecurity, spectrum policy, communications, command and control, and SATCOM.

The CIO follows an iterative process that feeds into the DoD PNT Oversight Council, a body of 19 senior leaders—service secretaries, combatant commanders, undersecretaries, and intelligence chiefs. Very senior, very busy people who lead large and important organizations.

All must work together to advise the Deputy Secretary and Secretary of Defense.

When Issues Cross Departments: The EXCOM 

For national PNT issues that fall outside the authority of either DOT or DoD/W, governance shifts to the National Space Based PNT Executive Committee (EXCOM), co-led by the deputy secretaries of Transportation and Defense/War.

SPD-7 tasks the EXCOM to “…make recommendations on sustainment, modernization, and policy matters regarding United States space-based PNT services to its member agencies, and to the President, through the Assistant to the President for National Security Affairs, or the Executive Secretary of the National Space Council, as appropriate.”

Not visible in the formal process is the Office of Management and Budget (OMB). Yet, OMB is arguably the most important and powerful component of the executive branch. The office drives budgets, oversees the President’s Management Agenda, and adjudicates cross-department issues and priorities. Without OMB support, department initiatives die on the vine.

The EXCOM meets once or twice a year and serves primarily as a coordinating body. Despite the many people involved, or perhaps because of it, the United States has:

• Lost its place as the leader in space-based PNT, and

• Failed to safeguard national and economic security with long called for alternative PNT capabilities

What About Leadership?

Bureaucracy is inherent in government. Strong leadership can often cut through it—especially in times of crisis—and overcome obstacles that stall progress.

Leadership, in fact, is an essential element of good governance. It is the energy that powers structures, processes and institutions. But governance structures matter as well. They can nurture and enable leadership, or they can constrain and frustrate it.

If no crisis demands action and authorities and responsibilities are unclear, initiatives become vulnerable to criticism or outright veto from those wary of change or protective of their organizational “lane.” 

Too many stakeholders can make collaboration unwieldy and give de facto veto power to individuals or groups who should not have it. And without a clear mandate from the top to achieve specific goals, even capable and determined leaders can find themselves blocked at every turn by an unwieldy governance structure and process. 

Time for a Reset 

Disruptions to GPS and other GNSS signals are increasing daily and are being seen more frequently in the homeland. Protecting the satellites, signals and their users is a national security and economic imperative. 

America has an abundance of technical expertise and commercially avail-able PNT products and services that can enable it to regain world leadership while guarding its national and economic security. 

It is time to reset our PNT governance and put these advantages to use. 

But this effort can’t be one of just “rearranging the deck chairs on the Titanic.” We need a whole new ship. 

America’s new PNT policy and governance must:

• Be about more than space. The need for one or more widely available backup and complementary sources of PNT for GPS in America is widely accepted. In a January 2021 report, the DOT found that combining signals from space with terrestrial broadcast and timing over fiber would constitute a core national resilient PNT architecture. That could be a great starting point.

• Identify and empower a “trail boss” or “first among equals.” Someone responsible for ensuring policies and plans are executed, timelines are met, and those responsible for action are held to account. Not a “czar,” but a champion tasked with bringing key actors and stakeholders together, developing a national plan, then ensuring it is executed.

• Establish specific goals and requirements for national PNT resilience. An updated policy and governance document doesn’t necessarily need to state accuracy, integrity, availability, and continuity requirements. But it should describe a resilient end state and draw the line between what utility-level services America’s national PNT architecture will provide, and what higher demand users must source for themselves. The core national resilient PNT architecture must be a backbone that other PNT systems and providers can leverage and build upon.

• A timeline to achieve the goals. For over two decades, national PNT policy has listed a variety of general and specific goals. None have had associated timelines and few have been achieved. A minimal resilient national PNT architecture of space, terrestrial broadcast, and fiber—the “resilient triad”—could be easily and quickly implemented. Mature technologies exist and can be available as products or performance-based service contracts. A target of five years would not be unreasonable for terrestrial components.

• Include OMB as an essential player. While SPD-7, and perhaps other national policy documents, discuss recommendations being submitted to the president, as a practical matter, that rarely happens, if ever. Instead, recommendations go to his personal management and budget staff—OMB. Unless they are on board, nothing happens.

Today’s PNT policy was published in the last few days of the first Trump administration. Its governance structure and processes are nearly identical to those used by the previous two administrations. In the five years since SPD-7 was published, the risk to the nation from over-dependence on GPS has increased significantly. It is time for this administration to break from its predecessors, forge a new path, and make America safer.

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“Celeste is a program that started not even two years ago, and we are already aiming to launch our first two satellites, what we call the IOD-1 and the IOD-2,” Giordano said. The satellites, now in orbit, are CubeSats flying at around 510 kilometers altitude.

“The objective of the mission is to demonstrate technology,” Giordano said. “This IOD [in-orbit demonstrator] phase is fundamental for us to master the technology, the techniques that we want to apply for future systems.” The satellites are designed to validate new positioning signals, multi-frequency capabilities, and integration with next-generation networks.

Giordano highlighted the wider scope of the Celeste program. “The two companies in charge of development are GMV and Thales Alenia Space France. They’re not just building the satellites. They’re also responsible for the ground segment and system-level development, including the very important specification phase, which will start as soon as the satellites are flying.”

Starting now

Celeste will operate across multiple frequency bands, Giordano said, “moving from UHF to other bands and potentially targeting indoor applications. Of course, L-band is a fundamental and master band we all need to provide. S-band has two phases: there is the S-band allocated to RNSS [radionavigation satellite services], used by GNSS systems today. But we may explore potentially usable MSS (mobile satellite service) bands, and will leverage 5G and terrestrial networks. “We also have C-band, one of the more appealing bands for resilience,” Giordano said, emphasizing the versatility and future-proofing of the system.

The IOD phase lays the groundwork for an operational LEO-PNT network. “At Ministerial ’25,” Giordano said, “ESA proposed the in-orbit preparation phase [IOP] that will follow.” First IOP satellites could be launched in the 2027-2028 timeframe. “When it comes to 5G and the current IOD satellites, we’re only testing the very basics, the physical layer,” Giordano said. “We will go beyond that in the IOP phase, where we plan to implement the full-scale 5G network capabilities.”

Looking ahead, Celeste is open to adding additional small constellations and experiments, offering opportunities for European industry and third-party participation. Giordano said, “We have a very strong ambition to bring into space operational services at European level in 2032, and we cannot do it with just demonstration satellites.”

With IOD-1 and IOD-2 now in orbit, ESA has taken its first tangible step toward a resilient, multi-band European LEO-PNT system, promising enhanced positioning, navigation, and timing services for the decades ahead.

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VIAVI Solutions and Ground Control have announced a partnership to integrate VIAVI’s Secure µPNT STL-1000 receiver module into Ground Control’s RockFLEET Assured maritime tracking and navigation platform, targeting vessels operating in GNSS-denied or contested environments.

The Secure µPNT STL-1000 is a compact, software-defined receiver that operates through VIAVI’s SecureTime altGNSS LEO service tier rather than relying on GPS/GNSS constellations. The module delivers precise timing with holdover capability — meaning it can maintain synchronization through signal outages — and is designed for what the defense sector terms Denied, Degraded, and Disrupted Space Operational Environments, or D3SOE. Its integration into RockFLEET Assured provides a secondary, independent position source alongside or in lieu of conventional GNSS, with the stated aim of sustaining navigation and vessel oversight when primary signals are jammed, spoofed, or otherwise unavailable.

“With jamming and spoofing now a core element of cyber warfare, resilient PNT solutions are no longer optional,” said Doug Russell, Senior Vice President and General Manager, Aerospace and Defense, at VIAVI. “Its compact size and low power consumption makes it ideal for applications that require an extremely small, low-power, secure, resilient embedded PNT receiver.”

Alastair MacLeod, CEO of Ground Control, framed the integration in terms of both commercial and defense exposure. “As the frequency of jamming and spoofing continues to rise, reliance on GPS/GNSS signals alone increasingly exposes both commercial and military operations to risk,” he said. “Integrating VIAVI’s Secure µPNT STL-1000 into RockFLEET Assured delivers a trusted secondary position source, strengthening resilience for mission-critical operations across defense, maritime and critical infrastructure environments.”

RockFLEET Assured is described as a marine-grade Assured PNT (A-PNT) solution. VIAVI, headquartered in Chandler, Arizona, and traded on Nasdaq as VIAV, positions itself as a provider of test, measurement, and optical technologies across defense, aerospace, and communications infrastructure markets.

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The Munich Space Summit remains one of the premier gatherings on the European space calendar, showcasing the accomplishments of leading industry players and policymakers. The Americans show up, too.

Despite current geopolitical strains, Europeans and Americans in the PNT and space communities continue to meet as collaborators, colleagues and, in many cases, longstanding friends. Conferences such as the Munich Space Summit are stronger for that transatlantic exchange.

One of the event’s key sessions, featuring program updates from the major satellite navigation providers, was moderated by Richard Fischer, publisher at U.S.-based Autonomous Media, the company behind Inside GNSS, Inside Unmanned Systems, Inside Autonomous Vehicles and xyHt.

“What strikes me most this year,” Fischer said, “is that the conversation around GNSS has clearly moved beyond constellation updates alone. Across the community, there is growing recognition that GNSS is critical infrastructure. It is no longer enough to think only in terms of accuracy and coverage. The language now is resilience, trust, authentication, continuity and assurance.”

Among the most anticipated appearances at the Summit was that of Christopher Erickson, the new U.S. Department of Transportation Director of PNT and Spectrum Management, succeeding longtime and widely respected GPS leader Karen Van Dyke. Erickson offered a sweeping overview of the current state of GPS, underscoring the extent to which U.S. positioning, navigation and timing (PNT) policy now involves a broad cross-section of government.

“It is very much a whole-of-government effort,” Erickson said. “NASA is addressing navigation beyond GEO and into the cislunar domain, developing plans for how position, navigation and timing will be provided in those environments. At the Department of Transportation, my office works across all transportation modes, including rail, highways and maritime, while the Federal Aviation Administration, of course, plays a central role in aviation. The Department of State is responsible for many of our international engagements with other global navigation satellite system providers, and the GPS system itself resides within the Department of Defense.”

It was the kind of summary that reminded the audience that GPS is no longer merely a satellite constellation, if indeed it ever was. It is a governance framework, a modernization program, a diplomatic instrument, a military capability, a civil utility and, increasingly, a resilience problem set. Erickson’s remarks made clear that no single office can now speak for the totality of the U.S. effort in PNT resilience. 

His overview continued in similar depth, and audience members received a concise but revealing tour of how GPS modernization, resilience planning and civil policy are being approached in Washington. Erickson was sharp, direct and notably comfortable speaking without presentation slides.

Off the Cuff

“One reason I did not feel it was essential to bring slides,” Erickson said, “is that GPS is, by design, a very deliberate and carefully managed system. If you have seen a GPS update in the last 18 months, you have likely seen many of the core elements already. That reflects our emphasis on stability, integrity and accuracy. We are cautious about implementing changes until we fully understand their implications.”

That observation may have drawn a few smiles, but it also underscored something important about GPS modernization: Progress in this domain is rarely theatrical. It is measured, highly scrutinized and often slower than outside observers would prefer. Yet, that caution is not accidental. It is built into the culture of a system on which aviation, defense, mapping, timing and countless commercial applications depend.

He then turned to the future of the constellation and the question of what comes after GPS IIIF.

“There are several avenues under consideration,” Erickson said. “We conducted a study known as R-GPS, or Resilient GPS, to examine how we might evolve the system while taking advantage of new capabilities and new thinking. That included looking at smaller satellites, shorter design lives, opportunities for multi-manifest launch, and ways to make the overall architecture less of a large, slow-moving enterprise and more agile, flexible and responsive, while preserving the accuracy and integrity on which users depend.”

He suggested a future architecture may not require every satellite to carry the same full set of functions.

“We also examined whether every satellite in a future architecture would need to carry the same full suite of capabilities,” he said. “If not, how might we distribute functions more effectively? How could space-based assets be used to complement one another? And how should such capabilities be distributed across orbit to deliver the most resilient and effective system?”

GPS may be deliberate in its evolution, but the strategic thinking around it is anything but static.

“We concluded that our primary focus should remain on MEO,” Erickson said. “At the same time, we launched the NTS-3 experiment, the first end-to-end navigation satellite experiment conducted by the United States in several decades. NTS-3 is exploring reprogrammability, ground responsiveness, user equipment implications, additional authorized signals, commercially relevant encryption approaches, and broader options for resilience. We hope to have initial results from that work later this year.”

Erickson also pointed to the Department of Transportation’s evaluation of complementary PNT technologies, an area of growing interest as governments seek to reduce overdependence on any single source of timing and navigation.

“We are close to releasing our first report covering approximately seven complementary PNT technologies,” he said, “and we are preparing to begin evaluating an additional group. In these efforts, we are procuring services from the companies involved and then assessing the technologies rigorously, from multiple operational and technical perspectives. The goal is to identify what these systems can do, where they perform well and where they may be appropriate within a broader PNT architecture.”

That is one of the most closely watched areas in U.S. policy today. The question is no longer whether alternatives or complements to GNSS exist. It is how they should be tested, how they should be compared and, most important, where they fit in a real operational framework. Erickson’s description suggested a government trying to move beyond abstract interest toward structured evaluation.

Another area gaining importance is PNT situational awareness.

“We have also begun a cross-government effort to create a shared data library,” Erickson said. “We already have several visualization tools and are continuing to expand and refine them. At the same time, we are engaging with international partners to share data and explore how to produce more comprehensive situational awareness products that can help inform decision-making as the interference environment evolves.”

Fischer then took the discussion in a broader direction, asking Erickson how the United States is thinking about the balance between maintaining an open global GNSS service and addressing the very real security concerns now moving to the top of the European agenda.

“If you are providing an open service,” Erickson said, “there are limits to what can be delivered solely by the service provider, and a significant portion of resilience necessarily resides with users and user equipment. That said, one important area I did not touch on earlier is authentication. It was not built into the civil service at the outset, largely because the scope of GPS’s eventual adoption was not fully anticipated. Today, however, we are working on out-of-band civil signal authentication that will be available to receivers with internet connectivity, and we are also advancing modernized civil authentication. Those efforts are proceeding in coordination with the U.S. Space Force as requirements are finalized and implementation moves forward.”

Forward with L5, but When?

The L5 signal is one of the most important modernization steps in GPS. More than simply an additional frequency, it represents a major advance in robustness, reliability and performance for safety-critical and precision applications. For aviation, surveying and other demanding user communities, L5 promises higher transmitted power, a stronger signal structure and characteristics specifically aligned with safety-of-life applications. First transmitted in 2005, however, it still has not been declared fully available for open-service users.

“We certainly have enough satellites on orbit transmitting L5 to support an initial capability,” Erickson said in response to an audience question. “By the time the tenth GPS III satellite is in the constellation, we expect to have 21. However, that is not the entire picture. The U.S. government has faced considerable pressure to declare the signal healthy, including under conditional approaches. But because L5 occupies a safety-of-life band, and because of what that means for our obligations with respect to integrity, we are not yet fully comfortable with the state of the overall enterprise.”

He made clear that the issue is tied not just to space assets, but to the ground segment and broader operational readiness.

“It is closely tied to the development of the ground system,” he said. “While I cannot provide a date today, we are continually reevaluating the situation and working toward bringing L5 forward as soon as we can do so responsibly.”

That answer led naturally to the larger issue of resilient PNT and the current U.S. posture.

“But stepping back to R-GPS,” Fischer asked, “what did the effort clarify, and how is the United States now thinking about resilient PNT more broadly?”

“That is an important question,” Erickson replied. “What you are seeing from the United States is an exploration of the boundary between what government should appropriately provide as foundational infrastructure and where the commercial sector should take the lead. The current administration has a strong interest in leveraging commercial capability wherever that is practical and effective.”

The question has resonance beyond the United States. When the European Union announced Galileo’s free High Accuracy Service, some commercial correction-service providers raised concerns that a government-backed free offering might disrupt existing markets. Ultimately, the market adapted, but the debate over where public provision should end and commercial opportunity should begin remains an active one.

“We are still working to define that appropriate boundary,” Erickson said, “what government should provide and what commercial industry is best positioned to provide in the context of resilient position, navigation and timing. I expect that this will eventually lead to a restructuring of broader PNT strategy. At present, however, we are in a data-collection and evaluation phase. NTS-3 is part of that. Our complementary PNT assessment effort is part of that as well. We are gathering the information needed to shape a coherent U.S. approach to resilient PNT moving forward, and I think we will see that picture come into much sharper focus over the next one to two years.”

The Timing’s Right

Timing, the “T” in PNT, is often overshadowed by navigation and positioning. Yet, it underpins telecom networks, power grids, financial systems and the digital infrastructure of modern life. Without precise timing, positioning solutions degrade, communications networks fall out of sync and critical infrastructure can quickly become unreliable. In Munich, timing was not overlooked.

Dana Goward, president of the Virginia-based Resilient Navigation and Timing Foundation, moderated a special Summit session on resilient time provision as a foundation of modern infrastructure. A longtime friend and collaborator of Inside GNSS, Goward is a familiar and respected figure in the transatlantic PNT community.

We caught up with him between sessions, where he explained the strategic framework he and others have been advancing.

“Timing is, and historically has been, a sovereign responsibility in support of both economic strength and national security,” Goward said. “At the RNT Foundation, and in some respects at the U.S. Department of Transportation as well, we have described a minimum resilient PNT architecture that includes what we call the resilience triad: signals from space, signals from terrestrial broadcast systems, and terrestrial fiber-based timing.”

The panel reflected that framework. Participants included Per Olof Hedekvist of Sweden’s RISE Research Institutes, an advocate for terrestrial backup systems such as eLoran; Stefan Baumann of IABG, who is active in resilient PNT testing, evaluation and system integration; Lisa Wörner of DLR, whose work includes resilient timing research, GNSS interference mitigation and alternative timing sources; and Tyler Reid, co-founder and CTO of Xona Space Systems.

Goward’s broader mission is to help policymakers understand the problem is solvable—and the tools to address it are already available.

“We have the technology, and in most cases it is not prohibitively expensive,” he said. “In many instances, elements of the solution are already in operation. What is needed is to bring them together coherently. At that point, the issue becomes one of leadership and governance.”

It is a message he has repeated often, and deliberately.

“We like to think of our work not as repetitive,” he said, “but as consistent. Staying on message matters.”

Storming Back

Another familiar and respected presence at the Munich Summit was Harold “Stormy” Martin, Director of the U.S. National Coordination Office for Space-Based PNT. As always, he offered pointed observations on the state of policy and implementation in the United States.

“We are in a relatively strong position in the sense that the policy guidance is clear,” Martin said. “Space Policy Directive-7, which was issued at the end of President Trump’s first term, speaks directly to resilience. Executive Order 13905 likewise calls on departments and agencies to strengthen resilience. So, the direction from the top-level policy framework is well established.”

By any measure, GPS remains one of the most consequential—and in some ways unexpected—success stories in modern infrastructure.

“There was never a plan for GPS to become the sole source of timing and navigation for federal departments or for critical infrastructure,” Martin said. “That does not appear in any White House policy document. Rather, we are in some respects dealing with the consequences of GPS’s extraordinary success. GPS and other GNSS services have been reliable, widely available and increasingly inexpensive to use. Receiver costs have fallen dramatically, and that has made GNSS the simplest choice for many budget-conscious decision-makers. Over time, alternative systems were reduced or eliminated, and some sectors now find themselves reliant on GNSS as their only remaining source of navigation and timing.”

That reality, he said, has created a strategic vulnerability that policymakers are now trying to address.

“It is an excellent system, and it has served us extremely well,” Martin said. “But every system has vulnerabilities. The signal originates roughly 12,000 miles away in space. It can be jammed. It can be spoofed. Those are not hypothetical issues.”

Current policy, he noted, places the emphasis on resilience, but implementation is inseparable from budget realities.

“Our policies are clear in telling organizations that they need to become more resilient,” Martin said. “The challenge, of course, is that these efforts remain subject to appropriations, and funding can be difficult to secure. Part of what we are trying to do is educate new decision-makers and create incentives for investment. You can already see some early steps in that direction. The FCC has issued a Notice of Inquiry on complementary PNT. That is part of building the record around what can be done to encourage industry to provide complementary PNT technologies that, together with GPS, can support a resilient and secure national PNT system of systems.”

How urgent is the issue? Martin suggested that current events are making the case more effectively than any abstract policy argument could.

“There is an old saying in Washington: Never let a good crisis go to waste,” Martin said. “If you look at the levels of jamming associated with conflicts in the Red Sea, in the Russia-Ukraine war and elsewhere, it becomes much easier to show leaders that this is not a theoretical concern. The objective is to strengthen our systems before that kind of disruption has domestic consequences.”

Getting Answers

A central part of the federal government’s effort to understand GPS vulnerability and evaluate alternatives has been the work conducted through the U.S. Department of Transportation’s Volpe Center. The so-called Volpe study has examined weaknesses in GPS-dependent operations while assessing candidate backup and complementary PNT technologies.

“Testing is essential,” Martin said. “And when we talk about mature technology, that includes practical readiness. One benchmark is whether a provider can bring equipment to a test site within six months. That is the kind of criterion that helps distinguish conceptual promise from deployable capability.”

The testing program is ongoing, and some reports are expected soon.

“The good news is that this is an achievable problem set,” Martin said. “We have policy guidance. We have demonstrated that credible technologies exist. The next step is determining how to invest. I have been making that case for 10 years, and I am more encouraged now than I have been in a long time.”

That closing note of cautious optimism matched the mood in Munich. The technical problems remain substantial. The policy questions are far from fully resolved. The funding picture is still uncertain. Yet, there is now a stronger shared vocabulary around resilience, a clearer understanding of the stakes and, perhaps most important, less hesitation about acknowledging that dependence on GNSS alone is no longer sufficient.

As temperatures outside dropped and snow began to fall over the Bavarian capital, the atmosphere inside the Summit remained warm and energetic, animated in no small part by speakers such as Erickson and Martin, and by the wider community now working to define what a resilient PNT future should look like. The concerns are real, the systems are under pressure and the architecture of the next phase is still being worked out. But in Munich, the conversation felt notably more mature than it did even a few years ago.

That, in itself, was one of the stronger signals to come out of the Summit.

And when this issue of Inside GNSS is presented at the Assured PNT Summit in Washington on April 7, it is likely that many of the same themes will be waiting there: resilience, authentication, complementary systems, timing assurance and the growing recognition that PNT must now be treated not simply as a technical service, but as strategic infrastructure. 

Munich did not resolve those questions. But it did provide a clear and timely snapshot of how seriously they are now being taken on both sides of the Atlantic. 

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At this year’s Munich Space Summit, something subtle—but significant—happened. What began two decades ago as a focused gathering of satellite navigation experts has merged with the faster-moving world of NewSpace. The NewSpace policy and industry concept marks a major shift in how the space sector works, transitioning from a government-driven sector to a more commercial, innovation-driven ecosystem, involving private companies, startups, and new business models.

The new Munich Space Summit, combining the Munich Satellite Navigation Summit and the Munich NewSpace Summit, clearly highlighted this shift and what it means for Europe’s space model and its vision for PNT. 

Bringing the Message Home

Bringing NewSpace into the fold means adding some of that agility to the deeply rooted PNT community. The PNT portion of the program brought together top space leaders to discuss how policy, programs and NewSpace pep can help them face pressing global challenges. Florian Hermann of the Bavarian State Chancellery offered some rousing opening remarks, referring colorfully to Germany’s significantly increased space-related spending. “Even in the mainstream in our society,” he said, “people know that we are facing something like a gold rush in space.” The country’s new budget marks a clear political shift toward space as a strategic, economic and security domain.

This joining of hands comes at a moment of intense concern about European defense and security, as war, geopolitical shifts and other threats converge, making Europe feel less secure than at any point in decades. Responding to that concern is the European Commission (EC), here in the form of Christophe Kautz, Director of Satellite Navigation and Earth Observation at DG DEFIS: “Let me be concrete about the new priority on which we are working. The Commission has developed quite large defense programs, and some of that is also going toward space. But in addition to that, we are also adapting what we already do with our space programs.”

Kautz described the EC’s proposal of a major new funding framework to boost Europe’s competitiveness. The Commission envisions a dedicated “space and defense window,” meaning a targeted funding stream for space infrastructure and defense capabilities. There will also be a focus on startups and SMEs, defense tech, as well as industrial scale-up and innovation.

“We’ve laid out what we want to do in the next finance period,” Kautz said, “…We are complementing our existing GNSS services, where we had a focus on the civil side, to make them also workable, or to tune them, toward the security and defense user.”

LEO PNT, he said, is the future and “can also be very useful for security and defense applications. When it comes to Earth observation, of course we’ve had Copernicus for many years, but we want to complement it with what we are calling an Earth observation governmental service, a PRS-like service in the realm of Earth observation.”

The EC is also hard at work on its new IRIS² communications initiative. “And we will have space surveillance and tracking,” Kautz said, “so we’re trying to tune our service portfolio toward security and defense.”

Forces at Play

ESA General Director Josef Aschbacher started his presentation on a positive note: “I just landed this morning from Washington D.C. where yesterday the new NASA administrator was announcing his vision of a Moon architecture, the Moon ecosystem, which is very interesting and where ESA has a lot of participation.”

On the changing geopolitical environment, his tone hardened. “The things we are seeing,” he said, “are drastically changing the landscape of space. We had a very successful [ESA] ministerial conference in Germany last November, and this was really Europe’s collective response to the new geopolitical reality. On the eastern side, of course, we have the war in Ukraine, on the western side we have the United States and the new geopolitical context in which we are living. My message to all the ministers of our ESA countries was Europe has to be stronger, more autonomous and self-reliant, and therefore we need space programs across the board where we are increasing our strength and capacity.”

At the Ministerial Council, member states agreed not only on a record budget of about €22 billion for 2026 to 2028, but also on a “clear defense and security mandate,” something ESA has traditionally avoided.

“We are working closely with the European Commission, and in general, we really want to build up the space economy,” Aschbacher said. “Europe has to change, we have to become faster, we have to rely on the ingenuity of our small and medium-sized enterprises.”

The European Union Agency for the Space Program (EUSPA) Executive Director, Rodrigo da Costa, expressed his approval of the new format. “In this new geopolitical situation, the response of the space sector is very important, to operationalize all of the space services for the security dimension, for the governmental users, which can be of a military nature.

“Our key focus,” he said, “has always been on how to serve a maximum amount of people, and I think we are there. The security users add another dimension, because they will be building key missions, key operations based on the services that we provide. This is required. As an ecosystem, as a sector, we are changing our focus, to serve this very particular set of users.”

Challenges Enumerated

Kautz reminded attendees it’s not going to be easy: “We have great ideas, and sometimes we are quite good at transforming these into something concrete. We do have some extremely good systems, but there are gaps. We do not have the investment power that they have in other parts of the world. This is linked perhaps to the way we are structured in Europe, some things that inhibit our investment capabilities. We are working on this.”

The European Investment Bank (EIB), launched a dedicated space financing initiative to support Europe’s space industry. The strategic fund mobilizes private and public capital behind space technology, infrastructure and companies.

“So there is some movement,” Kautz said, “and this is something that we need, to help turn our ideas into economic reality. I think we also have issues related to our regulatory environment. At least from the Commission’s perspective, we think we need an internal market for space. The proposed Space Act should lead us into this direction.” The EU Space Act, expected to take effect in 2030, sets unified rules for space activities, boosting investment, innovation, and strategic autonomy across Europe’s space sector.

Aschbacher added another complaint to the list: “We are fragmented. We are 27 EU countries, more than 20 ESA member states. We have to join forces, especially when we are under pressure.”

Aschbacher will be aware of recent reports suggesting Germany and possibly Italy may pursue their own national systems for sovereign communications, essentially duplicating the capabilities of the EU’s IRIS², which is aimed at providing shared secure connectivity.

“We seem to be going in the wrong direction,” he said. “The time is critical. If we go too far, in not linking up these different systems, it will be too late.”

Still Competitors, Still Collaborators

From across the great water, a lone American said his country still holds some security-related priorities in common with its allies. An old friend of the conference, Harold “Stormy” Martin is Director of the National Coordination Office (NCO) for Space-Based PNT within the U.S. Government. He assured the audience that while, “the world situation is not beautiful right now, President Trump’s PNT policies make it clear that the U.S. takes GPS jamming and GPS spoofing very seriously. We’re developing interference mitigation and detection measures.”

The event highlighted how NewSpace energy—speed, innovation, SME participation, and flexible architectures—is reshaping Europe’s space model and strengthening its vision for Galileo, LEO PNT and a more resilient space infrastructure designed to support economic growth, service continuity, and greater confidence in critical operations.

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