# Preparations for Galileo PRS in Poland
## 5 Polish Contribution for the PRS
### GNSS Jamming Tests in a Controlled Laboratory Environment
INT4 (Narrowband modulated carrier 4 MHz), one of the sophisticated jamming signals, had a significant impact on all of the tested smartphones. As the interference level was increased, the corresponding degradation of the decoded signal quality in the receiver (denoted as the SNR level) could be observed. The degradation rate was equal for GPS and Galileo. Further, the DOPs values were adversely affected. The most harmful impact was noticed for the Sony smartphone in both the Galileo and GPS scenarios, where the DOPs degradation was visible from the beginning of the jamming signal occurrence. On the other hand, for Samsung in the GPS mode, the increase of the DOPs values was much slower and smoother than in other smartphones, and after reaching the C/I cut-off value, they just dropped down to zero, denoting no fix. All the smartphones eventually lost their positioning capabilities, but the Huawei (in the Galileo mode) recovered this ability later, despite even higher interference levels. INT5 (Pulse), one of the sophisticated jamming signals, had a minor impact on the Huawei and Samsung smartphones, a moderate impact on the Google smartphone and a significant impact on the Sony smartphone. In some scenarios, the presence of the interference caused the degradation of the decoded signal quality in the receiver for each satellite (denoted as the SNR level), which was particularly noticeable for the 2 \(\upmu\)s pulse repetition period; for the Sony, the \"no fix\" state was even observed. The pulse jamming signal also caused the disturbances and increased the DOPs values. The most harmful impact was noticed for the Sony in both the Galileo and GPS scenarios, causing DOPs degradation for pulse repetition periods lower than 2 ms. In the presence of INT5, Sony lost positioning capability on several occasions, but in the Galileo mode, it happened more frequently than for the GPS mode. On the other hand, the Huawei and Samsung were mostly unaffected by INT5 in the Galileo mode, and for the GPS, their accuracy degradation was only observed for a few pulse signal repetition period cases. INT6 (Sweep), also one of the complex jamming signals, had a severe impact on all the tested smartphones in both the static and dynamic tests. In the case of the static tests, the presence of the interference caused a significant degradation of the quality of the signal decoded in the receiver for each satellite (denoted as the SNR level). On some occasions, after the application of the INT6 interferer, the useful signals were completely lost, and the DOPs values dropped down to zero, denoting no fix. The most harmful impact was noticed for all the smartphones in the GPS mode, where the positioning capability was lost for most swept signal configurations. In the Galileo mode, Google and Sony lost their positioning capability in most of the INT6 jamming cases. On the other hand, Samsung and Huawei in the Galileo mode were still able to determine their position, despite the presence of interference, and the accuracy degradation was noticeable only for Samsung. In the case of the dynamic test, the results were different than in the static one. Huawei almost completely lost its positioning ability in both the Galileo and GPS scenarios, and for Sony, the observed degradation of the positioning accuracy was rather moderate. Summing up, the simplest possible interfering signals, INT1 (Continuous Wave) and INT2 (Three Continuous Waves), had a minor to moderate impact on all of the tested smartphones. More sophisticated jamming signals, INT3 (Wideband AWGN noise L1/E1 60 MHz) and INT4 (Narrowband modulated carrier 4 MHz), had a significant impact on all of the tested smartphones. The complex jamming signals, INT5 (Pulse), had a wide range of impact levels on various smartphones, from minor to significant, and INT6 (Sweep) had a severe impact on all tested smartphones. In most cases, the Sony smartphone was the most vulnerable to the jamming signals, and in many cases, the DOPs degradation was visible from the beginning of the jamming signal occurrence.