INSPIRE INSPIRE – Instantaneous High-Accuracy Positioning Based on Hybrid GNSS

The INSPIRE project (Instantaneous High-Accuracy Positioning Based on Hybrid-Meta-Signal Solutions) represents a major leap forward in Hybrid GNSS and meta-signal processing. Leveraging peer-to-peer ranging techniques and sensor fusion, INSPIRE aims to address the persistent challenges of positioning in deep-urban environments and urban canyons. Traditional Global Navigation Satellite Systems (GNSS) often encounter degraded signals in these settings, leading to inaccuracies and reduced availability. By contrast, INSPIRE’s Hybrid GNSS approach is specifically designed to deliver precise, robust, and instantaneous positioning even under severe signal obstruction.

The Role of Hybrid GNSS in INSPIRE

“Hybrid GNSS” refers to a methodology that combines multiple GNSS constellations and integrates advanced signal processing techniques, such as wideband meta-signal processing, into a single, unified framework. Unlike conventional systems that rely heavily on a single GNSS constellation and narrowband signals, INSPIRE’s Hybrid GNSS concept broadens the signal bandwidth to improve code observables and overall resilience. This approach ensures that the receiver can maintain accurate position, velocity, and timing (PVT) solutions even when line-of-sight signals are partially blocked or distorted by tall buildings and other reflective surfaces.

Meta-Signal Processing

A key aspect of INSPIRE’s Hybrid GNSS design is meta-signal processing, which exploits wideband techniques to combine signals from multiple GNSS frequencies. This significantly enhances measurement accuracy and mitigates the effects of multipath interference—one of the biggest hurdles in dense urban settings. By effectively synthesizing these wideband signals, INSPIRE delivers higher signal fidelity, more precise ranging measurements, and faster time-to-fix metrics.

Peer-to-Peer Ranging for Cooperative Positioning

Another innovation that sets INSPIRE apart is its peer-to-peer (P2P) ranging capability. Through P2P modules, receivers in close proximity can communicate directly, sharing position and timing information. This cooperative method reduces reliance on potentially weak or obstructed satellite signals. In deep-urban environments, where visibility to satellites might be severely limited, peer-to-peer ranging can significantly enhance location accuracy and availability by leveraging nearby receivers as supplementary reference points.

Sensor Fusion and Hybrid Positioning Engine

INSPIRE’s hybrid positioning engine merges data from multiple sources, including inertial sensors, GNSS signals, and P2P inputs. This sensor fusion ensures that the final PVT solution is both accurate and robust to sudden signal dropouts or noise spikes. In dynamic scenarios—such as vehicles driving through tunnels or high-rise districts—this multi-sensor integration helps maintain a continuous and reliable navigation solution. Users benefit from reduced position drifts, minimized time to reacquire signals, and overall improved continuity of service.

Real-World Validation and Consortium

To validate the performance of this Hybrid GNSS approach, the INSPIRE consortium conducts rigorous field testing in diverse environments—ranging from open-sky rural regions to densely built-up city centers. Key Figures of Merit (FoMs) include PVT accuracy, service availability, and signal tracking quality. The consortium behind INSPIRE comprises leading researchers and industry experts:

• IGASPIN (Austria): Project coordination and integration of the SX3 software-defined GNSS receiver platform.

• Politecnico di Torino (Italy): Development of advanced meta-signal processing algorithms.

• Universität der Bundeswehr München (Germany): Hybrid positioning engine research and performance assessment.

• Famidat (Hungary): Peer-to-peer ranging module design and field trials.

Conclusion and Future Outlook

By advancing Hybrid GNSS technology through meta-signal processing and cooperative ranging, INSPIRE aims to deliver next-generation navigation capabilities with unprecedented accuracy and reliability. The project’s open, modular architecture allows for flexible integration of future GNSS constellations and emerging sensor technologies. As urban areas continue to grow in complexity, INSPIRE’s robust solutions offer a transformative path forward for precise positioning in even the most demanding conditions. Ultimately, this holistic approach—combining multi-constellation signals, peer-to-peer cooperation, and sensor fusion—represents a critical step toward truly ubiquitous, dependable navigation systems for intelligent transport, autonomous vehicles, and beyond.