# A Software Defined Radio Based Anti-UAV Mobile System with Jamming and Spoofing Capabilities
## 5 Real Environment Tests  
Several tests were accomplished in order to evaluate the performance of the complete anti-UAV mobile system under the influence of real GNSS signals. It is important to note that, in these tests, we focused mostly on the evaluation of the overall system against drones operating in automatic flight mode. Still, in a previous work of some of the authors [30], we had already presented several experimental interference tests using the adopted jamming solution, which showed that it was possible to disrupt the UAV communication link.  
For the tests presented in this paper, the BladeRF was powered by USB 3.0, with gains of TxVGA1 = \(-\)4 dB and TxVGA2 = 25 dB.  
For the operation of the system, it is necessary to select the forced landing site, intended for the forced landing of possible invading drones. We can see the selection adopted for the tests in Figure 11.  
In following figures, we illustrate the real test scenario, which corresponded to a rural environment, wherein it was possible to visualize the roof of a one-story house, bushes, some ground vegetation and a few trees. The tests were carried out in a fully controlled and safe environment.  
The drone used for the real-life tests was a DJI Phantom 3 Standard, illustrated in Figure 12.  
Figure 11: Real test scenario with selected forced landing site.  
Selecting the auto flight mode and with the drone already in flight, whenever the jammer signal transmission was started, the drone's behavior automatically changed, stopping its flight path and gliding in the same place.  
It was observed that the time between starting jammer transmission and drone gliding is almost instantaneous.  
If the jammer is started before the drone takes off, the drone will not even perform any action.  
All tests were performed safely, away from air traffic and outside prohibited areas.  
After the drone halts its operation due to jamming it was then possible to emit spoofing signals so that the drone was deflected and indirectly controlled.  
Figure 13 shows the test scenario. The UAV was pre-configured with an autonomous route marked in red in the image. As soon as the operator started transmitting jamming signals, the drone was hovering in the same place (ball marked in red).  
The remaining pre-configured route was not completed by the UAV.  
The anti-UAV mobile system operator (Figure 14) changed the mode of operation from jamming mode to spoofing mode.  
Figure 12: DJI Phantom 3 Standard.  
Figure 13: Real test scenario using jamming signals.  
With the operator pointing towards the target UAV, using the telescopic sight, if necessary, the geographical determination of the UAV was initiated.  
Through the sensor module, the location of the UAV was determined and, through the processor module, the spoof route to the forced landing site was generated.  
We can observe the whole scenario in Figure 15.  
When the UAV received the spoofing signals, it assumed its new route and moved to the forced landing site as desired. The system's performance was positive, and we managed to divert the drone at the four cardinal points. The UAV behavior was as expected with the theory; the spoofing behaved as shown previously in [21] regarding several well-known GPS receivers.