6.2 Subsystem Responsibilities

The communications subsystem is responsible for:

• Sending payload data to ground driven by the mission requirements,
  • Mission dependent
  • Wide range of data rates, bandwidth, criticality, …
• Sending spacecraft data (e.g. health, position, attitude) to the ground for operations, and
  • Attitude and acceleration data: sun sensors, star sensors, gyros, accelerometers, etc.
  • Housekeeping data: temperatures, pressures, voltages, currents, etc
• Receiving commands from the ground for operations

The communications subsystem specialist is responsible for:

• Defining a communication architecture, which includes spacecraft bus, and ground segments
  • Selecting a radio frequency and getting the license for that radiofrequency
  • Juggling the number and position of ground stations available to use

• Selecting and coding the compression, encoding, and modulation of signals to balance loss and bandwidth

• Select communications technology that adheres to mass, volume, power constraints, and regulations and fulfills mission requirements
• Verifying that the communication link budget closes based on the selected technologies and ground station architecture