ABSTRACT
Optical technologies for the transmission and processing of digital or analogue signals are widely used in terrestrial and underwater networks. Industrially mature for applications on the ground, this technology is now available for utilization on board satellites. Indeed two basic tendencies touch the space world today: • New requirements in terms of the flow of information, the reconfigurability of networks, reliability,
safety and economic constraints mean that the respective roles played by satellites and ground systems are being redefined. From being a simple rf repeater without any real-time data-processing on board, communication satellites in the future will have to ensure more complex functions including, for example, information processing, data routing, circuit switching, collection and diffusion of information towards a great number of individualized users etc. Traditional communication satellites are ‘bent pipe’ devices connecting two fixed points on the ground, managed by an operator. Information processing was carried out on the ground. Future satellites will have new missions such as multicasting-sending high rate data streams to thousands of end-users at an acceptable cost [1]. The significant number of users having simultaneous access to the satellite, the need for traffic management resulting from this and the need to simplify the terminal all shift complex operations towards the satellite.
