Interference-aware convergecast scheduling in wireless sensor/actuator networks for active airflow control applications

Emerging wireless sensor/actuator network (WSAN) technology has the potential to enable semiautonomous air-flow control to improve the aerodynamic performance of aircraft. In this paper, a WSAN comprising of multiple linear sensor clusters terminated by actuators is proposed for active airflow control with the objective of minimizing convergecast latency. Here the convergecast delay is defined as the time required from the beginning of a sampling period to all all sensor’s data of this sampling period is received by the actuator. The objective is achieved by minimizing the separation distance of concurrent data transmission so that the number of nodes sending data in the same time slot is maximized. The problem turns into a scheduling problem with a proper selection of interference separation. However, most existing work on the scheduling in linear networks use the minimum separation of 2 hops to avoid collisions. This paper examines the relationship between the hop separation, signal-noise-ratio and the latency to make a selection of interference separation. A new interference aware hybrid line scheduling (HLS) algorithm is proposed and its energy consumption is analyzed. Compared with other line scheduling policies. the analysis and simulation results show that, at moderately high node densities, the proposed HLS with carefully selected hop separation is able to reduce both the delay by up to 15 % and the energy consumption somehow.