SMOG-1 is Hungary's next satellite which is made according to the PocketQube standard. Its mission is to monitor the electromagnetic spectrum and measure ionizing radiation dose from low Earth orbit.
My task is to develop the on-board computer and its software for the satellite. In this work I will present how I designed the SMOG―1 on-board computer (OBC) and how it was made. The OBC is the subsystem which connects to all other parts in the satellite and controls, monitors and coordinates them.
The on-board computer hardware consists of an ARM Cortex-M microcontroller, RTCC (clock and calendar), flash memory and sensors that are the ”eyes and ears” of the satellite. All other subsystems connect to the OBC as peripherals: the communication subsystem (COM) and the electrical power subsystems from which the OBC collects telemetry. For high reliability, there are going to be two of each unit on board which will work in cold redundancy without any single point of failure.
The on-board computer software is tasked with controlling the satellite, collecting telemetry and managing the communications with the ground station which is going to receive signals from SMOG―1 using a 4.5 m parabolic antenna on top of BME building ”E”. The software is written using an ”event loop” architecture and runs in real time.