## 3 Results and Discussion  
The measurement campaign, conducted in October-November 2023, focuses on both impulsive and stationary signals, aiming to detect the various types of signals propagating in the air. To differentiate between them, the spectrum analyzer was configured by appropriately setting the resolution bandwidth (RBW) of the instrument. Specifically, for continuous signals, the RBW was set to a few hundred kHz (e.g., 300 kHz), which is why this is referred to as the \"narrow-band campaign\". In contrast, detecting impulsive signals requires a wider RBW, typically a few MHz (e.g., 3 MHz), which is why the measurement of impulsive signals is called the \"wideband campaign\". The mechanical measurement procedure involves several slow 360-degree rotations of the mobile laboratory's mast, where the antenna is mounted. The entire process lasts approximately 15 min, which is considered sufficient to map the general RFI scenario in the area of interest. During these antenna rotations, the spectrum analyzer is set to \"max hold\" mode, and the data are recorded. This process is repeated for each linear polarization of the antenna (i.e., horizontal and vertical), and the data are then combined. This approach ensures that all azimuthal directions are considered, allowing for an accurate mapping of the surrounding RFI environment. The amplitude level of the measured signals, since it does not cause compression of the components in the mobile laboratory's receiving chain, is not relevant to this study. In fact, the C-low receiver of the SRT is a more robust system than the mobile laboratory's front end, and there is no risk of it being saturated. The purpose of this study is to assess the frequency band occupancy of the unwanted signals detectable by the telescope. The results of the narrowband and wideband campaigns are presented in Figures 3 and 4, respectively. Regarding the narrowband campaign, Figure 3 shows a high presence of in-band signals in the 4.03-4.08 GHz, 4.23-4.37 GHz, 4.95-4.97 GHz, and 5.1-5.8 GHz frequency ranges. These signals are generally detected in all three measurement areas. However, in area number 2, signals were detected at 5.05 GHz that were not present in the other two areas. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Channel of the** & **Component of the Receiving Chain** & **Frequency** & **Gain at 5 GHz** \\
**Front End** & & **[GHz]** & **[dB]** \\ \hline
**Common for** & & & \\
**all channels** & Dual-ridge horn antenna, model DRG-118-A from A.R.A. Technologies & 1–18 & 11.6 \\ \hline \multirow{4}{*}{D} & Input switch, model RLC SR-6C-H from RLC Electronics & 0–18 & \(-\)0.3 \\  & Band-pass cavity filter, model 8 IZ5-4400/R2200-S from Lorch & 3.3–5.5 & \(-\)0.6 \\  & Output switch, model RLC SR-7C-H from RLC Electronics & 0–18 & \(-\)0.3 \\  & Amplifier, model AMF-6D-00101800-35-20P from Miteq & 0.1–18 & 42 \\ \hline \multirow{4}{*}{E} & Input switch, model RLC SR-6C-H from RLC Electronics & 0–18 & \(-\)0.3 \\  & Band-pass cavity filter, 8 IZ6-7200/R3600-S from Lorch & 5.4–9 & \(-\)0.4 \\ \cline{1-1}  & Output switch, model RLC SR-7C-H from RLC Electronics & 0–18 & \(-\)0.3 \\ \cline{1-1}  & Amplifier, model AMF-6D-00101800-35–20P from Miteq & 0.1–18 & 42 \\ \hline \multirow{4}{*}{**Common for** **all channels**} & External spiral coaxial cable & 0–18 & \(-\)15 \\ \cline{1-1}  & & & \\ \cline{1-1} \cline{2-4} \cline{1-1}  & & & \\ \hline \end{tabular}
\end{table} 
Table 1: Summary of the technical specifications for each component of the receiving chain. The most notable finding is that the 4.37-4.95 GHz window has the least RFI, and this frequency window is the most suitable for scientific applications. As for the results of the wideband campaign, shown in Figure 4, the same band occupancy is observed, except for the signals in the 4.23-4.37 GHz frequency range. These signals are evidently not detectable with the spectrum analyzer set to an RBW of 3 MHz and therefore are not attributable to the signals targeted by this campaign.