| This paper mainly studies several key technologies of industrial real-time communication and the design of embedded gateway.The first chapter is the introduction part,which mainly introduces the research background and significance of this paper,the development of industrial wireless network communication,the research status of wireless embedded gateway technology,the research status of time synchronization technology,the research content of this paper,etc.The second chapter is the introduction of related concepts,focusing on This paper introduces the concepts of time synchronization,embedded system,routing protocol and wireless LAN communication.The third chapter is the design of embedded wireless gateway,which is mainly discussed from three aspects: time synchronization scheme,real-time communication resource allocation design and cluster tree topology model design.The fourth chapter is the function test of wireless gateway,which focuses on the same time of wireless gateway Step function,resource allocation results and routing protocol simulation results are tested;the fifth chapter is the conclusion and prospect,which summarizes the whole paper and draws the experimental conclusion.This paper designs an FTSP algorithm based on WSN target location.Because linear regression needs a certain sample space,the larger the sample space is,the higher the accuracy of linear regression is.But WSN is computing power and storage space are limited,so FTSP algorithm only uses eight reference points for linear regression,so the linear regression algorithm is easy to be affected by abnormal data points,and the regression curve is fitted out More errors may be introduced,resulting in greater precision deviation,resulting in unnecessary calculation.Therefore,an improved scheme is proposed to correct the time drift rate a and improve the accuracy.In this paper,an LRT optimization algorithm is proposed to jointly optimize the cache placement strategy and bandwidth allocation to minimize the outage probability of the system.The network set in this paper is deployed in a square area,with the length of the side For L,sink node is located in the positive center of the network(L/2,L/2),and the location of sink node is fixed.All sensor nodes are randomly distributed in a square area,and the maximum transmission range of each node is R.if the distance between node A and node B is not greater than R,the two nodes can transmit data to each other;if the distance between nodes is greater than R,the transmission of the two nodes can only rely on the intermediate nodes Conduct.The simulation results of the improved algorithm show that:(1)In time synchronization,the average error of two nodes in single hop is 1.68?s for FTSP,1.61?s for improved FTSP,and the difference between the two is 4.2%;however,in the case of seven hops,the average error of two nodes is 11.7?s for FTSP,10.25?s for improved FTSP,and 12.4% for improved FTSP algorithm in multi hop network The average error difference of each hop is smaller and the stability is better.(2)In the aspect of communication resource allocation,only the gateway can broadcast data packets in the first slot,and its sub nodes can not apply the resources in this slot,which leads to no nodes in the second channel can apply.However,for the relatively large-scale industrial wireless network,resource waste is difficult to avoid completely.In addition,there is no scheduling in the 14 th slot and the second channel,which is largely caused by the topology.In addition,node 13 does not have any sibling nodes,and its parent node 9 does not have sibling nodes,which leads to a certain waste of data packet aggregation.(3)In terms of routing protocol,the routing overhead corresponding to WMDSR is much lower than that of the original protocol.The delay of WMDSR protocol is lower than that of DSR protocol.In addition,WMDSR can show ideal time synchronization performance in the actual process.Therefore,WMDSR can be effectively applied in wireless industrial networks. |
PDF Full Text Request