| As the current urban development gradually changes to intensification and informatization,it becomes particularly important to integrate urban resources and improve the modern management capabilities of the city.The urban infrastructure represented by the underground comprehensive pipeline corridor provides an effective solution to the current smart city governance.There are many pipelines in the pipe gallery and the environment is complicated.It is necessary to establish a complete monitoring system to remotely monitor the environmental conditions and equipment operating status.The rapidly development of wireless sensor networks has provided a perfect solution for the operation of the corridor comprehensive monitoring system.Using various energyconstrained miniature sensor nodes,various types of data in the corridor are collected and uploaded to the remote control center in real time.To ensure the stable operation of the system.In wireless sensor networks,there are two key technologies,routing protocol and positioning algorithm,which are particularly important.As the underlying technology,routing protocol provides data support for the upper-layer applications,which is the key to energy saving of the system.Positioning algorithm is the basis for making upper-layer applications meaning.This paper takes the wireless sensor network routing protocol and positioning algorithm as the research object,and combines the actual environment of the corridor to provide a solution for the efficient operation of the corridorc omprehensive monitoring system.The main research contents of this article are as follows:(1)Aiming at the problems of uneven energy consumption and short life cycle in data transmission,a gradient-based unequal clustering routing protocol(GUCRP)for heterogeneous wireless sensor networks is designed.The protocol firstly analyzes and models the environment of the corridor,calculates the optimal number of partitions from the perspective of balancing the whole network energy consumption,and establishes the virtual gradient partitions of the network by using the flooding mechanism.According to the gradient partition,calculates the optimal number of clusters to each gradient,and optimizes the clustering process of nodes.The residual energy of the nodes is introduced into the cluster head competition mechanism,and the cluster head competition radius is controlled according to the energy heterogeneity of the nodes to form non-uniform clustering.In the data transmission stage,the residual energy and distance factor are combined as a cost function to select the next best gradient forwarding node.The simulation results show that the protocol effectively balances the energy consumption,and extends the life cycle of 60.9%,24.8%,and 10.1% compared with other protocols,which can be effectively applied to the corridor network environment.(2)Aiming at the problems of node positioning due to multi-path effects,non-lineof-sight,etc.,leading to large errors of node positioning,an improved RSSI positioning algorithm is disigned.Firstly,the algorithm starts from the network coverage and establishes the beacon nodes rectangular deployment strategy through comparative analysis.Secondly,the error analysis of the RSSI positioning algorithm is performed to determine the optimization parameters.In the ranging stage,real-time path loss parameters are introduced into the wireless signal transmission model to reduce the ranging error,obtain the estimated distance of nodes,and introduce a distance correction factor to correct the RSSI ranging distance.In the positioning stage,the four-sided measurement method is used to calculate the coordinates of unknown nodes.The simulation results show that compared with the traditional methods,the improved RSSI algorithm can effectively reduce the node positioning error,improve the positioning accuracy by 19.4%,and meet the positioning requirements of WSN. |
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