Codes and balances: Multibeam satellite load balancing with coded packets

Aiming to exploit the capabilities of next generation terminals to receive and process several, partially overlapping beams of a multibeam satellite, we present a mathematical analysis and propose algorithms to provide enhanced and robust load-balancing to unequal load demands between beams. At the core of our mechanisms is a resource allocation problem that aims to minimize the time to deliver packets taking into account the load (traffic demands) per beam and channel conditions. Network coding is a key enabler of our mechanism, allowing a seamless and efficient exploitation of the multiple, available paths from satellite gateways to end-users and leading to a more efficient allocation of resources in each beam. Advantages over current state-of-the-art for load balancing for multibeam satellites include: i) cooperation amongst neighboring beams to improve system stable throughput, ii) use of random linear network coded packets to enhance reliability and simplify the allocation of packets to the different beams, and iii) adaptation to short-term dynamics of the traffic of each beam, instead of only long term traffic characteristics. We provide numerical results for the case of a multibeam satellite covering Europe with 70 beams showing that our technique can increase the stable throughput by 30% or higher with respect to current techniques.