Research Of Wireless Wake-up Mechanisms Based On Traffic Adaptation

Recently,with the increasing demand for portable supplies in the application of Internet of Things technologies,Wake-up Radio(WuR)has become a research topic for wireless sensor networks(WSNs).It allows the idle wireless terminal nodes' microcontroller unit(MCU)to go to sleep,and wake up when packets arrived.And it have a dramatic reduction in energy consumption.In this thesis,the WuR protocol is proposed to effectively reduce the WuC loss probability and energy consumption in the star and tree WSNs for the problems that packets loss probability and energy consumption are too high in the traffic changing network.The main contents of this thesis include:1.A dynamic Clear Channel Assessment(DCT-WuR)wake-up protocol is proposed for the problem that the latency and energy consumption are too high during the Clear channel Assessment(CCA).The nodes in this protocol use multiple CCAs when the channel is idle,and only execute once when busy.In this way,the node can enter the sleep state more quickly.2.Aiming at the problem that the DCT-WuR protocol has a high wake-up calls(WuC)loss probability in the traffic changing star WSNs,a dynamic adaptive wake-up protocol(DNAP-WuR)based on the WALB algorithm is proposed.This protocol uses the Quasi-Newton Methods to nonlinearly fit the historical information,and obtains the node quantity comparison table by the Exponentially Weighted Moving-Average method.And the nodes estimate the remaining nodes number according to the actual backoff,CCA execution times and the comparison table,and increase or decrease the backoff time upper limit according to the nodes number and the packet arrival rate.3.Aiming at the problem that the DCT-WuR protocol has a high WuC loss probability in the traffic changing tree WSNs,a packets continuous transmission adaptive selection wake-up protocol(PCT-WuR)is proposed.The wake-up protocol analyzes the two states of light and heavy traffic,and sets the threshold according to the maximum packets processing speed of the second-level node.When the traffic is light,that is,the packet arrival rate is less than the threshold,the requesting nodes are allowed to send two packets after sending a WuC.When the traffic is heavy,that is,the packet arrival rate is greater than the threshold,a single packet transmission mode is adopted.Finally,this thesis improves the node loss probability model to analyze the WuR wake-up protocols above based on the M/G/1/2 queue.Compared with CCA-WuR,the DCT-WuR reduces 54.60% in delay and 28.03% in energy consumption in the star network.Compared with CSMA-WuR,DNAP-WuR increases 9.19% in throughput.Compared with CCA-WuR,the total delay of DCT-WuR is reduced by 23.16% in the tree network.The PCT-WuR has 21.48% reduction in delay,and 23.09% decrease in WuC loss probability.