The STRIKE3 project ran for 3 years from February 2016. The main activities included a state-of-the-art review, development of standards for threat reporting and for receiver testing against threats, and validation of the standards through long-term monitoring and testing of selected receivers.
The main objectives of the state-of-the-art review were the identification of potential stakeholders and their challenges, analysis of existing monitoring and testing programmes and initiatives, and the identification of existing standards. A thorough literature review was performed and a questionnaire circulated to stakeholders to gain feedback on standardized interference reporting and testing. The main findings have been published the RIN Journal of Navigation in a paper entitled “GNSS Threat Monitoring and Reporting: Past, Present, and a Proposed Future”.
The standards development work looked at two areas: threat reporting standards and test standards. The reporting standards focused on a standard message format, content and definitions to allow standardised reporting of interference events. The test standards activity has focused on methodologies for identifying and selecting threats for testing, as well as the approach to testing GNSS receivers’ resilience to such threats. These draft standards are freely available from the project website.
The reporting standards have been validated through long-term monitoring from a global network of monitoring sites. This validation demonstrated the improved compatibility of reports from different systems when using the reporting standards, and has also built up an extensive database of interference events and signatures, allowing in-depth analysis to help understand the scale and nature of GNSS interference in the real world. The monitoring shows a significant amount of interference affecting all sites, although there is a wide variation in the level of activity between different sites depending on the type of infrastructure and the local environment, with busy sites (e.g. city centres) suffering most from interference. Despite the very high numbers of detected events, the vast majority were low power and short duration and do not cause any impact on GPS tracking. We also see much more unintentional than intentional interference. However, there are still many hundreds that cause a complete loss of GPS positioning at the monitoring site. In terms of the signals themselves, the work has identified the types of signals that pose most threat, i.e. those that are most common in the real world.
The receiver testing activity has tested a range of receiver types (mass-market, professional, etc.) against interference signals identified from long-term monitoring. The tests show that receivers have some resilience to the threats, i.e. they can continue to track satellites and provide position for some level of interference. However, the level of resilience is dependent on several factors, including receiver type, interference signal type, and GNSS (i.e. GPS vs Galileo). As each type of receiver reacts differently to the interference, and depends on configuration settings, this demonstrates the importance for procurement authorities, application developers, etc. to test their receivers’ in the configuration that will be used for their application.
Activities related to long term monitoring and receiver testing, as well as demonstrations of the reporting and receiver testing, have been presented at two STRIKE3 workshops. In addition, several presentations have been given at various conferences and a public summary of the results (D6.2 and D8.2) are available from the STRIKE3 project website.
