Fault detection and eigenstructure optimization in IEEE 802.11 wireless sensor actuator networks for building automation

There are signs that wireless sensor actuator networks can be used in time-sensitive industrial processes to reduce cable deployment and increase flexibility. This paper investigates the time-sensitive fault detector design in wireless sensor actuator networks subject to random packet delays and packet losses. The impacts of wireless packet delays and losses are modeled as external unknown disturbances and a memory block is introduced to deal with the packet losses and long delays. A frequency component estimation method is proved to estimate the frequency of these unknown disturbances. An eigenstructure optimization method is proposed to enhance the fault detector's sensitivity to the fault and the robustness against the delays and packet losses. The fault detection performance in a wireless building automation system is demonstrated by hybrid MATLAB/NS2 simulation.