A satellite bus (or spacecraft bus) is the main body and structural component of a satellite or spacecraft, in which the payload and all scientific instruments are held.
Bus-derived satellites are less customized than specially-produced satellites, but have specific equipment added to meet customer requirements, for example with specialized sensors or transponders, in order to achieve a specific mission.
The Integrated Truss Structure (ITS) of the International Space Station (ISS) consists of a linear arranged sequence of connected trusses on which various unpressurized components are mounted such as logistics carriers, radiators, solar arrays, and other equipment. It supplies the ISS with a bus architecture. It is approximately 110 meters long and is made from aluminium and stainless steel.
View the full Wikipedia page for Integrated Truss StructureThe space segment of an artificial satellite system is one of its three operational components (the others being the user and ground segments). It comprises the satellite or satellite constellation and the uplink and downlink satellite links.
The overall design of the payload, satellite, ground segment, and end-to-end system is a complex task. Satellite communications payload design must be properly coupled with the capabilities and interaction with the spacecraft bus that provides power, stability and environmental support to the payload.
View the full Wikipedia page for Satellite space segment