One Year On-Orbit Results of Improved Bus, LoRa Demonstration and Novel Backplane Mission of a 1U CubeSat Constellation*

The BIRDS series from Kyushu Institute of Technology has deployed 1U CubeSat constellations from International Space Station since 2017. BIRDS-3 was deployed in June 2019. Lessons learnt from BIRDS-1 and BIRDS-2 have been used to improve the bus system of BIRDS-3. Improvements have been made in On-Board Computer, Electrical Power and Communication systems. BIRDS-3 has implemented novel Backplane Mission which uses SoftCIB; an in-house designed software defined backplane interface board. The mission has the potential to standardize interface and cut down on development time. BIRDS-3 project has placed a LoRa module to check its performance in space. The module has the potential for future low-cost, low-powered Store and Forward mission and CubeSat communication system. This paper provides detailed information on the improved BIRDS bus system, LoRa Demonstration and Backplane Mission designs, and onorbit results since its deployment in June 2019. The results presented are based on cumulative operation time of three years for three satellites operating each for a year. The satellites are functional and will remain in orbit until summer of 2021.