Final Report of BeJamDetect Project 
accurs only in a single measurement epoch. The interference effect cannot be identified in the plots 
for the receiver performance metrics - the mean C/NO in Figure 4-17b, the number of GNSS 
satellites in track and used for PVT in Figure 4-17c and the height component of the receiver PVT 
solution in Figure 4-17d. All receiver performance metrics show a nominal behaviour. No 
interference effect can also be observed on the extimated poistions produced by the Demonstrator 
2 which are shown in Figure 4-18 for the entire month. 
The analysis results shown for the first month of the measurement campaign - May 2022 — allow 
to conclude that harmful radio frequency interference can only be identified if only a combination 
af RFI detection and receiver performance metrics are used in a combination. Individual spikes or 
suspicious short-time behaviour of a single metric does not necessarily indicate an effect caused by 
GNSS Jamming. 
An example of a systematic interference effect that can be identified by using a combination of 
several metrics can be illustrated by analysing the RFI event occurred between May, 15 and May, 
18: 
In this time the RFI detection metric has permanently increased (see Figure 4-16). 
But also the number of used GNSS satellites and the mean of their C/NO values noticeably 
decreased (see Figure 4-14 and Figure 4-13, correspondingly). 
RFI detection metric 
72 12, 2222, 29:09:36 
7 9.601029 
HL 
20:40:00 20:41:00 20:42:00 20:43:00 20:44:00 20:45:00 
UTC time May 12, 2022 
a) RFI detection metric 
Time evolution of PRNs In PVT and In track 
Aim9 SYDIOD 97 DAN LER 
|=—=@— used for PVT 
Im = ‚tracked, GPS L1-C/A 
— iracked, GAL E1-B 
+ 
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Time evolution of mean CNO value: 
50 
_ CL + ag vn a 
| X May 12, 2022, 20:40:36 Y 
ı Y 48.86 # — GPS | 1-C/A |. 
——GALE1-B | 
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a 
H 
7,40 
235 
ä 
A 
Ay 
OH 
20:40:00 20:41:00 20:42:00 20:43:00 20:44:00 20:45:00 
UTC time May 12, 2022 
b) mean C/NO 
Estimated WGS-84 height —_ 
"—— = height 
. | X May 12, 2022, 20:40:36 
Y 52.6 * 
53 
| 
52.8 
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51.8 
51.6 ! 
, 1.4 
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20:40:00 
Fitle: Final Report 
Version: 1.0 
— — = BL NL, ) 
20:42:00 20:43:00 20:44:00 20:45:00 se 20:41:00 20:42:00 20:43:00 20:44:00 20:45:00 
UTC time May 12, 2022 UTC time May 12, 2022 
c) number of satellites d) estimated WGS-84 height from PVT solution 
:igure 4-17: A close-up view of potential Jamming event on 12-May, 20:40 UTC 
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