Research And Application On A Frequency Hopping Decision Mechanism For Wireless Sensor Networks

In industrial applications,wireless sensor networks require high stability and reliability of data transmission.When the wireless sensor network is used in industrial field,it is is susceptible to the same frequency interference and environmental noise,resulting in the loss of data.Among them,the same frequency interference has the most serious influence on the communication quality,which may cause the networks disabled,frequency hopping technology is one of the important methods to solve the same frequency interference problem.The paper relies on the development and application of the temperature and humidity monitoring system of the wireless sensor network in the Qianjiang cigarette factory of Chongqing.The traditional single-node detection of frequency hopping mechanism is sensitive to environmental noise and commonly generates false frequency hopping actions,leading to the networks communication burden increase and the reliability of data transmission decreases.This paper is studied to tackle the problems mentioned above.The research contents and achievements are as follows:(1)A channel quality estimation algorithm based on feature change of RSSI value is proposed.Based on the experimental research platform,the receiver signal intensity indicator(RSSI)is used as the channel quality evaluation parameter.By comparing and analyzing the influence of the same frequency interference and environmental noise on the quality of wireless networks channel,the quality of the channel with the change of RSSI is extracted,and then a channel quality evaluation algorithm is proposed,providing a reliable basis for networks frequency hopping technology.(2)A frequency hopping decision mechanism based on distributed detection is proposed.Based on the distributed detection algorithm,this paper uses the node's local frequency hopping decision mechanism to vote on the networks frequency hopping,introduces the node's local decision weights and then weights the node's credibility,uses voting results of decision center fusion node to generate networks frequency hopping decision,make a comparison between the node voting result and the networks frequency hopping decision,dynamically adjust the local decision weights of nodes,and suppresse the influence of environmental noise on traditional frequency hopping mechanism.Simulation experiments show that,compared with the traditional single-node detection frequency hopping mechanism,the proposed method improves the systems interference identification rate and reduces the probability of erroneous frequency hopping.Further,in the SimpliciTI protocol,a distributed frequency hopping decision mechanism is implemented and physical networks verification is performed.The frequency hopping decision mechanism can effectively identify the environment noise interference and the same frequency interference,make effective frequency hopping decision,reduce the blindness of frequency hopping and improve the stability of the networks communication.The distributed frequency hopping decision mechanism provides a guarantee for the stable and reliable data transmission of wireless sensor networks and has certain applicability,possessing great significance to the wireless sensor networks frequency hopping communication technology.