# TinyGS vs. SatNOGS: A Comparative Analysis of Open-Source Satellite Ground Station Networks
## 5 Discussion
### Comparison of the Number of GSs That Were Online in the Last 24 h on 29 July 2023
As for SatNOGS, approximately 40% work only in the UHF band, 31% in the VHF, and 25% in the VHF and UHF bands ([VHF, UHF]). As can be seen in both figures, for both projects, the highest percentage of GSs work in the VHF, UHF, and [VHF, UHF] bands. The reasons for this are due to the fact that most satellites work in these bands. Comparison of the Number of Satellites That Were Operational and Managed to Send Data to the GSs Even If That Data Has Not Been Decoded as of 29 July 2023  
In this section, and in the following three sections, satellites will be discussed. For SatNOGS, we took the satellites that were operational according to the SatNOGS Database on 29 July 2023, while for TinyGS, we only took the satellites classified as \"supported\" in the TinyGS web application [23] and that were operational according to the SatNOGS DataBase. Why are the \"supported\" satellites chosen for TinyGS? As previously mentioned, one of the functions of the TinyGS network is to decide with which satellite the GS will communicate. The decision is made only taking into account the satellites classified as \"supported\". \"Inactive\" satellites, as the name implies, are inactive (even if they are still operational and in orbit according to the SatNOGS database), so when the TinyGS network has to decide which satellite the GS will communicate with, it does not count the \"inactive\" satellites, but only the supported ones. That is why, for TinyGS, we only select the \"supported\" satellites. In addition, only currently operational satellites were selected because those that re-entered the atmosphere or are inoperative are no longer of interest. To verify that the satellites were operational, the NORAD of satellites and the SatNOGS DB API [11] were used, and it was verified whether the status of each satellite was equal to \"alive\". Finally, and regarding this topic, it was decided to study the number of satellites that saw their data being received by the GSs, even if those data had not been decoded. Why were these satellites without decoded data chosen? This was because the data were being received  
Figure 9: Bands used by SatNOGS GS in the last 24 h of 29 July 2023.  
correctly, it was just not possible to decode the data because the decoder had not yet been made available or implemented. The numbers are as follows:  
* SatNOGS: 611;
* TinyGS: 25. As we can see, within the operational satellites, the number of satellites with which SatNOGS was able to communicate, even if the data were not decoded, was almost 24 times greater. However, it is also necessary to bear in mind that TinyGS only has the main objective of communicating with LoRa satellites, and therefore, a much lower number was expected. Observation of the Frequencies of the Satellites That Were Operational and Managed to Send Data to the GSs Even If This Data Has Not Been Decoded as of 29 July 2023  
In Figure 10, it is possible to see the frequencies of the satellites that were operational (according to SatNOGS DataBase) and classified as supported (according to the TinyGS web application) on 29 July 2023 and that had at least one data packet received by a TinyGS GS. To see if the satellites were operational, the SatNOGS DB API [11] was used. To see if they were supported, their frequencies, and to check if the TinyGS GSs had received packets from that satellite, the TinyGS web application was used [23]. Additionally, if one counts the number of satellites in Figure 10, one will see that it is not equal to the 25 mentioned above. This is fundamental, as there are satellites, such as SATLLA-2B and ThingSat, capable of communicating with more than one frequency. Although, for example, TinyGS supports the 437.25 and 2401 MHz frequencies in SATLLA-2B, most of the packets received, if not all, are received with a frequency of 437.25 MHz. However, the satellite transmits on that frequency (2401 MHz), and since the TinyGS allows it to receive packets with that frequency, it was decided to place it in the histogram.