A Cross-Layer Control Based on Fuzzy Automata for Ad-Hoc WLAN QoS

This paper proposes a new interface model for crosslayer designs using generalized fuzzy automata (GFA) and fuzzy control. When using the proposed model, an upper layer is reduced to an adaptive and cognitive controller and the lower layers act as hierarchical plants. In this paper, we utilize the model in wireless LAN Quality of Service (QoS). The fuzzy controller allocates bandwidths for different traffics, detects saturation of performances, and criticizes satisfaction of traffic specifications (TSPECs). The distributed fuzzy controller adaptively tunes its fuzzy sets according to both the TSPECs and the network states. According to the realization theory and the experiments, the adaptive QoS controller fulfills TSPECs no matter what dynamics of the TSPECs and the network environment are.