# An Accurate GNSS Spoofing Detection Method Based on Multiscale Eye Diagrams
## 5 Experimental Results on the TEXBAT Dataset
### Receiver Operating Characteristic Curve Experiment  
Each of the cases (1, 2 and 3) was tested individually for a total duration of 410 seconds. In these cases, spoofing attacks typically occurred between the 90 th and 120 th seconds and persisted until the conclusion of the signal. To assess the efficacy of time-domain transient detection more accurately, we calculated the detection rate at 10-second intervals. We established a false alarm rate \(P_{f}\leq 0.01\) and a predetection integration time \(T_{d}=100\) ms. Case 1 in TEXBAT involves a scenario in which the attacker first blocks the real signal and then quickly switches to a spoofing signal that is weaker than the real signal. The receiver platform is static. Although the power of this spoofing signal is weaker than that of the real signal, it never coexists with the real signal. The results of the detection process are illustrated in Figure 6. During the first 120 s, the spoofing signal is not activated, and the detection rates of all methods are less than the false alarm rate of 0.01 that was established. When the spoofing signal is subsequently activated, the curves of each detection method begin to change. In particular, after the spoofing signal begins, the instantaneous detection rate of the EDDM-MSC-MMP exhibits a pronounced increase, reaching a sustained 100% detection rate after 140 seconds. Interestingly, the curves (e.g., Slope, Delta, ELP) of the detection methods that rely only on the change in correlation peaks in the I-channel lag significantly behind the other curves, with a detection rate of less than 10%; \begin{table}
\begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Detection Method**} & \multicolumn{6}{c}{**Minimum Acceptable Detection Rate**} & \multirow{2}{*}{**30\%**} \\  & & **95\%** & **90\%** & **80\%** & **70\%** & **60\%** & **50\%** & **40\%** & **30\%** \\ \hline Slope & 0.98\% & 0.98\% & 1.02\% & 1.09\% & 1.09\% & 1.29\% & 1.63\% & 2.77\% \\ Delta & 0.00\% & 0.00\% & 0.05\% & 0.11\% & 0.41\% & 0.88\% & 2.34\% & 4.13\% \\ Ratio & 0.00\% & 2.29\% & 10.18\% & 19.50\% & 29.52\% & 38.05\% & 45.49\% & 53.06\% \\ ELP & 0.18\% & 0.45\% & 1.63\% & 2.72\% & 3.72\% & 5.51\% & 7.05\% & 9.82\% \\ Slope+Delta & 1.02\% & 1.07\% & 1.09\% & 1.27\% & 1.84\% & 2.95\% & 4.10\% & 7.35\% \\ Ratio+ELP & 0.86\% & 5.03\% & 18.25\% & 28.16\% & 34.76\% & 42.70\% & 49.43\% & 56.33\% \\ CN0 & 0.75\% & 0.95\% & 1.75\% & 2.34\% & 3.17\% & 6.37\% & 22.93\% & 50.25\% \\ EDDM-MSC-MMP & 95.35\% & 95.94\% & 96.37\% & 96.67\% & 96.96\% & 97.10\% & 97.32\% & 97.57\% \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Coverage of various detection methods. Figure 6: Detection rate of each detection method for Case 1 of the TEXBAT dataset. this is because Case 1 is a spoofing-switching case, where there is no overlap between the spoofing signals and real signals and where the correlation peaks change very little when the spoofing signal arrives. Although the Ratio method also performs detection on the basis of the correlation peak changes, it utilizes both in-phase and quadrature signals for detection, and the detection performance is better than the Slope, Delta, and ELP methods. The combined detection methods are all better than the single-metric detection methods, but their performance improvement is limited. The CN0-based detection method also has a low detection rate because of the small change in CN0 in Case 1. In TEXBAT Case 2, the spoofing signal is 10 dB higher in power than the real signal. Additionally, the phase difference between the carrier of the spoofing signal and the real signal is not maintained at a fixed value, and the receiver platform is stationary. Figure 7 illustrates the efficacy of each detection method in Case 2. In this case, the spoofing signal is superimposed from the 100 th second onward. In contrast to Case 1, the detection methods have distinct detection rates, as well as varying response speeds and detection rate.