Final Report of BeJamDetect Project 
Distribution of the RFI wrt. the detection triggering 
in 2021 
L400 
L200 
L000 
300 
500 
400 
200 
D 
June 
Julv 
August 
September October November 
{until 11.11) 
a) total number of RFI detections per month 
Distribution of the RFI above weak level wrt. the 
APin in 2021 
300 
250 
200 
L50 
L00 
50 
3 
June 
Julv 
August September October 
& 
November 
{until 11.11) 
3 Weak RFI | 1< APin<3 [dB] #@ı Medium RFI | 3 <= APin<5 [dB] I Strong RFI | 5 < APin [dB] 
b) with respect to the input power variation caused by the RFI event 
Figure 3-30: Distribution of the RFI occurrences in L5 during the 2021 campaign 
The strongest interference events happened mostly in the first two months, accumulating 471 of 
the 507 occurrences that increased the input power above 1 dB. As such, the largest portion of 
strong events also happened in June and July, with the most affected areas by strong interference 
around Heligoland and Rostock. Moreover, the majority of these events were caused by 
DME/TACAN signals [12, 13], which is confirmed by the position of the ship during these events 
and the positions of DME/TACAN stations close by. On Figure 3-31 these positions are plotted on 
a map. From the 40 strong events, 28 are DME/TACAN (possessing the same signal structure of 
these systems), 4 were wideband noise-like RFI and 8 were composite RFI cases made of 
DME/TACAN and wideband noise. 
Nitle: Final Report 
Version: 1.0 
age: j4