New results in stable switching congestion control for satellite TCP/AQM networks

In this paper, a stable congestion controller using data-driven, safe switching control theory is proposed to improve the dynamic performance of the satellite TCP/AQM networks. First, the stable region of the Proportional-Integral (PI) parameters for a nominal model is explored. Then, a PI controller, whose parameters are adaptively tuned by switching among members of a given candidate set using observed plant data, is presented and compared with some classical AQM policy examples, such as Random Early Detection (RED) and fixed PI control. A new cost detectable switching law with the interval cost function switching algorithm is developed, which improves the performance and saves the computational cost; it is then compared with a law commonly used in the switching control literature. Finite-gain stability of the system is proven. Fuzzy logic PI controller is incorporated as a special candidate to achieve good performance at all nominal points with the available set of candidate controllers. Simulations are presented to validate the theory.