The Communication Subsection designs and develops all the systems needed to communicate with and on the CubeSat. Current projects include the construction of our own ground station and a fail-safe bus system that will be used on our satellite. In our hardware-related projects, we mainly work with the programming languages MicroPython and C(++); Python is also used in many projects.

System design

When designing a communication system, it is important to focus on the reliability of the system in order to maintain constant control over the satellite. To ensure this, we decided to use CCSDS standards for radio transmission and for command and data processing, which are used in commercial spaceflight, at ESA and NASA.

The communication system comprises the ground station, the communication board in the satellite, the on-board bus developed in-house and the forwarding of data from the ground station to the mission control centre. We work closely with the On-Board Computer Subsection to define requirements and standardize interfaces.

On-Board Bus

The various subsystems of a CubeSat need a reliable and fail-safe way to communicate with each other and exchange commands. Since there is currently no common solution for this, we have developed the SpaceCAN together with LibreCube. This is based on the CAN bus, which is widely used in automation and the automotive sector. By adding a redundant line and mechanisms to restore operational capability in the event of a failure, a critical „single point of failure“ is eliminated and the probability of success of the entire mission of the satellite is increased.

Groundstation

In order to be able to receive satellites, a so-called ground station is required. A ground station is able to continuously angle one or more antennas towards the satellite during an pass and thus maximize the signal reception.

In the course of a bachelor thesis at the IAT, such a ground station was developed and the components were designed in such a way that both satellites and rockets can be tracked with it.

For the ongoing test operations, the ground station was equipped with an L-band antenna and is thus able to receive high-resolution images of the weather satellites NOAA 18 and NOAA 19. To share this achievement with the open source community, the station is connected to the SatNOGS network.

Got interested?

No matter whether you come from electrical engineering, physics or a completely different course of study, you are always welcome here, as the tasks are varied and we can learn, tinker and create something great together. Are you interested or do you have any further questions? Then just email the team leader Alexander Klingeberg or Leo Göttlicher. Our meetings take place regularly on Wednesdays at 17:30 on our Discord server in the voice channel #cs_communication.