# TinyGS vs. SatNOGS: A Comparative Analysis of Open-Source Satellite Ground Station Networks
## 5 Discussion
### Comparison of the Block Diagrams  
In the first instance, consider the block diagram of a fixed SatNOGS GS with only one omnidirectional antenna. Compared to a rotator SatNOGS GS, Figure 3, the fixed SatNOGS GS has no rotator, diplexer, or controller and its power supply. Consequently, we would have the LNA connected directly to the antenna. In this way, the main difference between a fixed SatNOGS GS and a TinyGS GS is the presence of an SDR since the LoRa module \"replaces\" the Raspberry. In terms of construction, the difficulty remains practically the same, but in terms of costs, it becomes extra. The cost of the SDR will vary depending on which option one chooses, but, for example, if one opts for a commonly used SDR, the RTL-SDR, then the cost is around EUR 30. Now, comparing the block diagram of a rotator GS, Figure 3, with that of a TinyGS, Figure 5, in addition to the SDR, there is the controller, the rotator, and the diplexer. Unlike the previous case, now both difficulty and cost increase considerably. Concerning the level of difficulty, it varies based on the choice between building a custom rotator or opting for a commercial one. Constructing a custom rotator presents a more complex challenge. For example, assuming that all necessary materials are already available, assembly of a TinyGS ground station can be completed in a single day. On the other hand, building a rotator SatNOGS GS (with SatNOGS rotator v3 and SatNOGS rotator controller v2.4) might take a few days. As for costs, they increase significantly, particularly with the mentioned rotator and controller alone, potentially adding at least EUR 400 to the expenses, depending on the reader's location and component accessibility. Comparison of the Difficulty and Time in Building and Configuring the GS and Uploading and Updating the Software  
During this comparison, certain considerations will be taken, such as already having the LNA, filter, Raspberry or LoRa module, diplexer, SDR and/or the materials to build the remaining components (antenna, rotator, and controller). Obviously, when talking about the SDR, diplexer, rotator and controller, these only refer to SatNOGS. Comparing fixed SatNOGS GSs [17] with TinyGS GSs exclusively in terms of GS construction, without antenna construction, both have low difficulty. Constructing a custom antenna produces a slight increase in difficulty, though the level will depend on the specific type of antenna chosen. For instance, building a turnstile is relatively simpler than building a QHF antenna. However, a rotator SatNOGS GS with a SatNOGS rotator v3 [17; 19] is highly difficult since the construction of the rotator and controller system is more challenging, and this will considerably increase the time needed to build it. Again, this difficulty can vary if one intends to build the antennas and which antenna one chooses. Regarding GS configuration and software upload in SatNOGS, although it is relatively easy compared to TinyGS, it becomes more complex and more susceptible to problems. In the case of SatNOGS, it is necessary to download the latest Raspbian SatNOGS Image (artifacts.zip) from the wiki [17] or GitLab, flash the SatNOGS image (img file) to a micro SD card (using, e.g., Balena) and then into the Raspberry Pi. Then it is time to do the SatNOGS Client setup. To do so, one needs to go to the Raspberry's console and run \"sudoraspi-config\" and then \"sudo satnogs-setup\". Next, one needs to set up, at least, its basic configuration option by setting its API Token (go to SatNOGS Network -> Dashboard -> API key), its RX device (set trlsfar if one is using an RTL-SDR), elevation (in meters), and so on. Furthermore, depending on its GS components and the performance of its GS, some parameters may need to be changed or added in the advanced configuration option. Lastly, remember to click \"Apply\", otherwise the configuration will not be saved. Following this step, the ground station will be ready, and its presence can be observed on the SatNOGS network, as indicated by \"Last seen, 0 min ago\" [17].