Final Report of BeJamDetect Project 
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Pre-whitening (i.e. pre-correlation null-steering) diagram is computed which allows 
to see If spatial nulls are produced and estimate the direction(s) of arrival of the RFI 
signal(s); 
Proprietary messages of uBlox Neo F10T receiver in binary form: 
o  C/NO values of the satellites in track; 
PVT information; 
Jamming and spoofing detection flags. 
An example of the Demonstrator 3 GUI in the case of a strong RFl-event on L1 is in Figure 5-1: 
The PSD-plot and the spectrogram for the L1 band in the tab in the middle bottom part of 
the GUI clearly show the presence of a man-made broad-band interference. In the PSD- 
plot, the difference between the estimated nominal PSD-curve in blue and the current PSD- 
zurve In yellow can be observed. Large parts of the frequency spectrum between 1560 MHz 
and 1580 MHz are distorted by the interference. 
The interference signal is wideband and continuous-time as plotted in the spectrogram. 
The L5/E5a band (the ”L5 band spectrum” tab, in the bottom right part) looks to be not 
affected by the interference. 
The C/NO-plot (top right corner) indicates unusually low values for L1-band GPS (deep blue 
pars) and Galileo (yellow bars) signals. 
The interference detection flags (in the middle, on left side) show that both the DLR 
techniques as well as the uBlox receiver detected the jJamming. The interpretation of the 
spoofing flags is not so clear. The DLR technique based on the correlation of the steering 
vectors finds a strong spatial correlation between the individual satellites. This is due to the 
fact that a strong jamming signal appears on all outputs of the PRN-code correlators of L1- 
pand signals. The processing gain of the PRN-code correlation is not sufficient in this case 
to fully mitigate the interference. The mechanism behind the yellow warning flag for 
spoofing raised by the uBlox receiver is not clear. 
The direction of arrival of the jamming signal can be estimated by examining the pre- 
whitening diagram in the ”Interference direction-of-arrival estimation” tab in the left 
oottom corner. The most likely estimation of the jammer DoA is marked on the diagram. 
The presence of a strong side-lobe in the diagram may be due to the multipath propagation 
or reflections of the Jamming signal. 
An example of GUI in case of an RFl-event on L5 is shown in Figure 5-2. The DLR technique for 
jJamming detection was still able to detect even such weak interference. The uBlox receiver looks 
to be less sensitive or more conservative in ralsing the corresponding detection flag. 
An example of GUI in case of RFI-free, nominal GNSS signal conditions is shown in Figure 5-3. 
Title: Final Report 
Version: 1.0 
ade: 76