A Polling Control Protocol with Energy-saving for Wireless Sensor Network

A polling control protocol for wireless sensor network (WSN), namely Sleeping controlled Point Coordination Function (S-PCF) was proposed based on IEEE 802.11 PCF and then the access control method of S-PCF was analyzed. In S-PCF, the center AP decides the sleeping time for every node so that it can synchronize the service with the nodes and maximize the sleeping time of each node to reduce the energy consumption coming from center AP's empty polling and the idle listening of the active nodes in PCF. The single direction transfer mode was introduced to simplify the data transmission for the data acquisition environment and the number of the data frame's subkinds was cut down so that the control can be lighten. Moreover, the transmission of the polling frame and data frame were also described in detail. Finally, the experimental results indicate that S-PCF can greatly save energy of idle nodes and extent the lifetime of wireless sensor nodes and the simulations also show that S-PCF can satisfy the system performance.