| S-Net | |
| Manufacturer: | Technische Universität Berlin |
| Country: | Germany |
| Applications: | inter-satellite communications |
| Orbits: | Low Earth Orbit |
| Operator: | Technische Universität Berlin |
| Lifetime: | 1 year |
| Status: | In Service |
| Built: | 4 |
| Launched: | 4 |
| Operational: | 4 |
| Autoconvert: | off |
| Power: | solar cells, batteries |
| Equipment: | S-Band transceiver |
S-Net is a worldwide inter-satellite communications network consisting of four satellites and being operated by Technische Universität Berlin.[1]
The project has the goal to investigate and demonstrate inter-satellite communication technology within a distributed and autonomously operating nanosatellite network. All satellites are equipped with a S-Band radio emitter and receiver, which not only enables communication with the ground-based control center but also allows for communication between the individual satellites.[2] The number of satellites in the network was set to four as this number represents the best cost-benefit-ratio. With four satellites, a total of six independent communication links are possible, while only three are possible with three satellites. Moreover, four is the lowest number that enables multi-hop communication.[3] The satellites are powered by solar cells and batteries and have a planned lifetime of one year.[3] Future applications of the technology may be more effective monitoring of global issues like climate change, disaster management, maritime systems monitoring and even enable satellite constellations for high-bandwidth internet access.[1] [3]
The four satellites were successfully launched on a Soyuz-2.1A rocket from Vostochny Site 1S in Russia on 1 February 2018. The launch was originally scheduled for 22 December 2017, however due to the failure of a Soyuz-2.1B rocket, Roscosmos decided to delay the mission.[2] The spacecraft were released into orbit at an altitude of approximately 580 kilometers at an interval of 10 seconds. The launch represents the tenth mission of the TU Berlin, sending a total of 16 satellites to space.[1]