## 3 Simulation Parameters and Scenarios
\begin{table}
\begin{tabular}{c c} \hline \hline
**Parameter** & **Value** \\ \hline \begin{tabular}{c} Orbit height \\ Multibeam pattern \\ Frequency \\ System bandwidth \\ Channel bandwidth \\ \end{tabular} & \begin{tabular}{c} 600 km \\ At least 19 beams of the hexagonal form \\ S-band \\ 30 MHz \\ Space-to-Earth: 30 MHz divided by frequency reuse factor \\ \end{tabular} \\ \
\begin{tabular}{c} Beamwidth \\ EIRP \\ Maximum antenna gain \\ Satellite G/T \\ Traffic model \\ UE antenna height \\ \end{tabular} &
\begin{tabular}{c} 4.41 degrees \\ 34 dBW/MHz \\ 30 dBi \\ 1.1 dB/K \\ Full buffer \\ 1.5 m \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Simulation parameters of NTN satellite. \begin{table}
\begin{tabular}{c c} \hline \hline
**Parameter** & **Value** \\ \hline \
\begin{tabular}{c} Antenna type and configuration \\ Polarization \\ Antenna gain (dBi) \\ Antenna temperature (K) \\ Noise figure (dB) \\ Tx transmit power \\ \end{tabular} &
\begin{tabular}{c} Omni-directional \\ Linear: \(\pm 45^{\circ}\) X-pol \\ 0 \\ 0 \\ 290 \\ 200 \\ 200 mW (23 dBm) \\ \end{tabular} \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Handset characteristics that were used in the simulations. Figure 1: Interference scenario between NTN network operating in the 1980–2010 MHz and Starlink operating in the 1990–1995 MHz. Interference from Starlink to MSSs is expected to be most common in regions where countries using MSS equipment are geographically close to those adopting Starlink's n25 band for direct-to-device connectivity. SpaceX has initially planned to employ the n25 band in collaboration with T-Mobile in North America. However, considering the global reach of the Starlink satellite system and the fact that the n25 band is supported for smartphones worldwide, it is likely that expansion into other regions will be on the horizon. This expansion will be especially significant given the band's global compatibility with smartphones across all regions. Therefore, in our study, we consider interference to MSS user equipment, which is located in the desert area of African continent where satellite services will likely to be used since such remote areas do not have terrestrial networks coverage. Figure 3 illustrates the interference scenario between the MSS system operating in the 1980-2010 MHz band and Starlink Generation 2, which operates in the n25 band. Figure 3: Interference scenario between NTN users and terrestrial users. Figure 2: Illustration of the allocation of the beams of the NTN satellite used in simulations. The characteristics of the MSS system were derived from the ITU-R filings. The MSS system characteristics that were simulated in the study are presented in in Table 3.  
For the Starlink satellite system, we gathered simulation data from the Federal Communications Commission (FCC) records and applications. Specifically, our simulation involved 1694 Starlink satellites. It is worth noting that in practical deployments, the number of satellites could be considerably larger, as Starlink has announced plans for more extensive constellations. The simulation of Starlink satellites closely adhered to the specifications provided to the FCC. Table 4 outlines the simulation parameters employed for modeling the Starlink system. For both Starlink and NTN, each beam of the multibeam antenna used the pattern that was based on Recommendation ITU-R S.1528 [11], which describes typical antenna patterns for NGSO satellites in the frequency ranges below 30 GHz; these antenna patterns are commonly used for compatibility studies in the ITU-R study groups and for frequency coordination between the satellite systems [12]. While it is important to acknowledge that the antenna patterns described in the recommendation are essentially approximations, real-world tests and measurements have consistently demonstrated their validity and applicability. These patterns, despite being theoretical representations, have been proven to closely align with the actual performance of NGSO satellite communication systems in practice.