Performance assessment of a multi-frequency subsystem for a small satellite space communication
Date of Issue2018-09-12
School of Electrical and Electronic Engineering
The successful launch of the six Singapore satellites in December 2015 enables the expansion of the space industry in Singapore via either space based research project or experimental products for commercialization purposes. These satellites are used for remote sensing applications as well as experimenting payloads for space study applications. The communication system on board the satellite plays a pivotal role in establishing contact with the ground station. It performs Telemetry, Tracking and Command (TT&C) which relays critical information such as the satellite’s health status and specific mission related data of the payload. Similarly, it has to achieve ground to space communication for scheduling further missions. For satellite projects with shorter development time, commercial off-the-shelf (COTs) communication system with space heritages are utilized. However, this imposes several issues on the satellite platform design, such as fixed data rates, requirement of higher link margin and restriction on integration to the satellite bus due to physical dimension. Additionally, traditional hardware based radio devices limit cross-functionality and can only be modified through physical intervention. This dissertation analyses the performance assessment of the communication subsystems that have space heritage to cater for Near Equatorial Orbit (NEO) application, which is of high interest to Singapore due to the increase in revisit rates. These subsystems, which are exceptionally important for small satellite development for both local universities and companies, will be reviewed through past satellite projects done in NTU to assess significant parameters such as achievable data rates, transmission power and RF propagation characteristics that are required when deducing the communication subsystem. Additionally, the software defined radio architecture will be examined to determine the feasibility of implementation for small satellites. The software defined radio provides the convenience of using customary computing environment to enhance interoperability and evaluate prevalent modulation schemes across multiple satellite program.
DRNTU::Engineering::Electrical and electronic engineering