Flexible satellites: software radio in the sky

Regenerative satellites with on-board processing offer great advantages for multimedia applications as they improve the global budget link and decrease the transfer delay when on-board packet switching is achieved. Meanwhile, they are often considered not flexible enough to follow evolution of services and transparent payload satellites are still used. This paper focuses on the introduction of flexibility at the satellite payload level. Two types of flexibility are considered: parameterization and re-programming. Firstly, the degree of flexibility is examined for the on-board digital and packet processes. Secondly, the support for flexible architectures is pointed out. The adaptation to the satellite environment of the software defined radio concepts and of the recent telecommunication works on the flexibility paradigm are analyzed. The FPGA approach for satellite payload is also detailed.