# Cost-Effective Satellite Ground Stations in Real-World Development for Space Classrooms
## 3 Satellite Signals Accessible and Decodable for Educational Purposes
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline  & **Acronym** & **Frequency BW Polarization** & **End of Life** & **Protocol** & **EIRP** & \
\begin{tabular}{c} **Transmission** \\ **Continuous** \\ \end{tabular} &
\begin{tabular}{c} **Longitude/** \\ **Orbit** \\ \end{tabular} \\ \hline
1 & FY-2G [2; 3] & \
\begin{tabular}{c} 1687.5 MHz \\ Linear BW 1 MHz \\ \end{tabular} &
\begin{tabular}{c} 2023 \\ (extended) \\ \end{tabular} & S-VISSR & 57 dBm & Every 30 min & 99.7\({}^{\circ}\) E/GEO \\ \hline
2 & FY-2H [2; 3] & \
\begin{tabular}{c} 1687.5 MHz \\ Linear BW 1 MHz \\ \end{tabular} &
\begin{tabular}{c} 2027 \\ \end{tabular} & S-VISSR & 57 dBm & Every 30 min & 79.2\({}^{\circ}\) E/GEO \\ \hline
3 & GK-2A [4] & \
\begin{tabular}{c} HRIT 1695.4 MHz \\ Linear polarization/ \\ BW \(\leq\)1 MHz \\ \end{tabular} &
\begin{tabular}{c} 2029 \\ \end{tabular} & HRIT, LRIT & 55 dBm & Every 10 min & 128.2\({}^{\circ}\) E/GEO \\ \hline
4 & GOES-R [5] & \begin{tabular}{c} 1694.1 MHz \\ Linear polarization BW 1.2 \\ MHz \\ \end{tabular} & \begin{tabular}{c} 2027 \\ \end{tabular} & \begin{tabular}{c} HRIT/ \\ EMWIN \\ \end{tabular} & \
\begin{tabular}{c} 56.8 dBm \\ \end{tabular} & Every 5 min &
\begin{tabular}{c} 75.2\({}^{\circ}\) W/104 \({}^{\circ}\) \\ W/138\({}^{\circ}\) W GEO \\ \end{tabular} \\ \hline
6 & Electro-L N3 & \begin{tabular}{c} 1691 MHz \\ RHCP \\ \end{tabular} & \
\begin{tabular}{c} 2029 \\ \end{tabular} & xRIT & N/A &
\begin{tabular}{c} Scheduled \\ 9 times/day \\ \end{tabular} & 76\({}^{\circ}\) E/GEO \\ \hline
7 & Electro-L N4 & \begin{tabular}{c} 1691 MHz \\ RHCP \\ \end{tabular} & \
\begin{tabular}{c} 2033 \\ \end{tabular} & xRIT & N/A &
\begin{tabular}{c} Scheduled \\ 3 times/day \\ \end{tabular} & 165.8\({}^{\circ}\) E/GEO \\ \hline
8 & Meteor M2-4 [6] & \begin{tabular}{c} LRPT 137.1 MHz, \\ HRPT 1700 MHz \\ \end{tabular} & \
\begin{tabular}{c} 2029 \\ \end{tabular} &
\begin{tabular}{c} LRPT, \\ HRPT \\ \end{tabular} & N/A & Continuous & LEO \\ \hline
9 & NOAA POES (15/18/19) & \
\begin{tabular}{c} APT 137.1-137925 MHz \\ HRPT 16980-1707.0, 50 MHz \\ \end{tabular} & N/A &
\begin{tabular}{c} APT, \\ HRPT \\ \end{tabular} & 33.5 dBm & Continuous & LEO \\ \hline
11 & ARISS [10] & \begin{tabular}{c} 145.800, 145.825 MHz \\ BW 10 kHz \\ \end{tabular} & \begin{tabular}{c} 2030 \\ \end{tabular} & \begin{tabular}{c} SSTV, voice, \\ APRS \\ digipeater, \\ AX25, NFM \\ \end{tabular} & \
\begin{tabular}{c} 25 W \\ \end{tabular} &
\begin{tabular}{c} Continuous, \\ time schedule \\ \end{tabular} & LEO \\ \hline
12 & LoRa CubeSat &
\begin{tabular}{c} 437 MHz \\ BW 62.5 kHz (SF8) \\ \end{tabular} & - & LoRa & 10 dBm & Depends & LEO \\ \hline
13 & \begin{tabular}{c} Immarsat \\ Aero/STD-C \\ \end{tabular} & \
\begin{tabular}{c} STD-C \\ Aero \(\sim\)1545 MHz \\ RHCP \\ \end{tabular} & - &
\begin{tabular}{c} Aero, \\ STD-C \\ \end{tabular} & N/A & Continuous & GEO \\ \hline
14 & ADS-B & 1090 MHz & - & 1090 ES & 46 dBm [11] &
\begin{tabular}{c} Broadcast \\ coverage in \\ line of sight \\ \end{tabular} & Sky \\ \hline
15 & \begin{tabular}{c} Air band voice \\ communication \\ \end{tabular} & \begin{tabular}{c} 118-135 MHz \\ BW \(<\) 10 kHz \\ \end{tabular} & - & AM & \
\begin{tabular}{c} 40 dBm \\ [12] \\ \end{tabular} &
\begin{tabular}{c} Broadcast \\ coverage in \\ line of sight \\ \end{tabular} & Sky \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Example of accessible signal in space and the sky. Figure 3: Examples of satellites that the satellite ground station in this research can receive and decode signals from. The signals from satellites collected in this research can be categorized into six types:  
* Geostationary Meteorological Satellites: These include Fengyun-2 (FY-2) [2; 3], GEO-KOMPSAT-2A (GK-2A) [4], Electro-L, and GOES satellites [5], which can downlink multispectral images. * LEO Meteorological Satellites: These include Meteor M2-4 [6] and NOAA POES [7; 8; 9]. * Amateur Radio Communication Satellites: These include the Amateur Radio on the International Space Station (ARISS) [10].