For wireless local area network（ WLAN）

the most popular protocol is IEEE 802. 11

which defines two different channel access mechanisms

i. e. distributed coordination function（ DCF） and point coordination function（ PCF）. Specifically

DCF works based on the mechanism of competition

which may lead to collision and uncontrollable delay for the acquisition data by station connected with sensors while transmitting in channel.Nevertheless

PCF works as a non-competitive access mechanism using round enquiry way

which can control the delay efficiently. Aiming at this case

utilize centralized control protocol to achieve PCF access mechanism

structure of superframe is defined in the protocol and each superframe is divided into a plurality of time slots

so as to realize non-competitive channel access mechanism. Experimental results show that the maximum access delay is controlled within 90 ms.