# Preparations for Galileo PRS in Poland
## 5 Polish Contribution for the PRS
### Galileo PRS Threats Detection  
Over the course of the 3 PfD project, the Galileo E1 and E6 bands were monitored to detect incidents of intentional and unintentional interference that could potentially degrade the Galileo PRS receiver performance. The data were collected from sensor sites (STRIKE-P) in five participating countries: Belgium, Germany, Finland, Poland and Sweden. All detected events were then classified and assigned to different categories (signal types) with different priority, and subsequently, new records were added to the 3 PFD Threat Database. The Polish STRIKE-P station was installed in the headquarters of the future Galileo PRS governmental authorized user in Warsaw (see Figure 3). The monitoring station was composed of two Protector Units for the E1 and E6 bands and a rooftop antenna with a clear sky view. The monitoring station was active for over a year (from 20 August 2020 till 29 September 2021).  
The overall statistical analysis of all the events recorded in Poland in the E1 and E6 bands shows that in the E1 band, the interference was observed for less than 2% of the station work time, but in the E6 band, for almost 5% of that time. The average duration of the interference in the E1 band was evenly spread throughout the entire period of the measurement campaign and amounted to a few seconds. Despite the differences in the number of events over time, no correlation was observed with respect to their average duration, and the longest detected interference incidents lasted about 100 s. The situation was different for the E6 band, where the average interference duration value was much greater than in E1. In this case, high mean values (approx. 50 s) were noticed for several months in a row between December 2020 and April 2021 and in July and August 2021. The three longest interferences in the E6 band, lasting 35, 46 and 49 min, occurred on two consecutive days in September 2021. The histogram of the interference duration time in both the E1 and E6 bands in Poland is presented in Figure 4.  
Figure 3: The Polish STRIKE-P monitoring station.  
It can be easily seen that due to the coexistence of Galileo and amateur services in the E6 band, there is a need to closely monitor this part of the spectrum; some regulatory decisions might also be required, as was mentioned in Section 4.  
It is worth noting that during the measurement conducted in the project, cases of the same interference types were detected at the same time in different parts of Europe, which indicates deliberate jamming activity across Europe, probably coming from the space segment of one of the satellite systems. In the face of a growing number of detected incidents and due to the tense international situation, the NIT introduced the concept of the Polish system for GNSS threats detection. The first major component of this system, i.e., the GNSS Galileo Mobile Measurement Platform (Polish acronym: MSP2G) dedicated to monitoring the quality of satellite navigation services and to detecting the threats to GNSS' integrity and availability, has just been developed in cooperation with the Chancellor of the Prime Minister, which also financed this initiative. Work is currently underway on the development of further components of the national GNSS threats detection system.