The WSN used in power line monitoring is long chain structure, and the bottleneck near the Sink node is more obvious. In view of this, A Sink nodes’ cooperation mechanism is presented. The Sink nodes from different WSNs are adjacently deployed. Adopting multimode and spatial multiplexing network technology, the network is constructed into multi-mode-level to achieve different levels of data streaming. The network loads are shunted and the network resources are rationally utilized. Through the multi-sink nodes cooperation, the bottlenecks at the Sink node and its near several jump nodes are solved and process the competition of communication between nodes by channel adjustment. Finally, the paper analyzed the method and provided simulation experiment results. Simulation results show that the method can solve the funnel effect of the sink node, and get a good QoS.
In our country, power transmission line is all over the land. Overhead lines exposed to the atmosphere are prone to failure, or even lead to disaster, and we need to find a simple method to monitor the line in real-time [
The wireless sensor network (WSN) technology penetrated from the field of military reconnaissance to industrial areas in recent years, which became the most popular areas of wireless networks. At present, the main practical applications of wireless sensor networks are ZigBee [
The distance between adjacent towers is from dozens of meters to hundreds of meters, even across the valley, rivers and other special cases, it is no more than one thousand meters [
WSN based power transmission line monitoring system has characteristics as following: 1) The system needs to manage a long chains tree-like topological structures so that transmission is essentially multi-hop. 2) They all periodically collect data and transfer them to a concentrator station connected to a fixed network. 3) From the mobility point of view, all the systems can be considered to be stable. Sensors are not mobile and the network is stationary during the transmission. 4) Nodes are equipped with GPS. And the node localization, time synchronization can be solved by GPS. Each node has a unique ID number, uniformly distributed in the network initialization. 5) The node energy is not restricted. 6) For real-time data transmission, the system have higher demand to the reliability.
To build Multi-mode layer network, the multiple Sink nodes are set in the network. The data collecting sensor network is divided into several levels [
Network with long chain type as an example, we assume that the node communication coverage 3 units. If the network is not layered, the number of the nodes within a node communication scope is about 20, and the 20 nodes compete wireless channel in the Communication. Through the network Level division, some nodes within the coverage area will be in the level of other bands, and only communicate with the edge nodes. Thus nodes to competition channel will be reduced to eight.
In the distributed coordination of DCF model access control mode [
Sensor network as a graph G = (V, E, SC), among them, the Sink node set, SC said V sensor nodes, the nodes if u and V can direct communication, are contained in the collection of E an edge (u, V). For each node in this paper, the modeling algorithm need the support of four list: NL neighbor node list, the parent node list PL, list of CL and brother child node SL.
In the node deployment, each node set up their own hop count to infinity, the node transmission power control unit is in a jump distance, network connection with probability 1. Then, each node broadcast network news, so that a node can know the existence of all its neighbor nodes, and the information stored in the NL list. Jump and then set the Sink node values, such as network exists in three Sink node, it will Sink node hop count is set to 0, 1, 2 in turn. Then choose the hop of 0 to the Sink node in the network broadcast a hello message, the message contained in the Sink node jump numerical and Sink node number value. When a node u v from the node receives a
hello message, after get jump numerical Nv, then use your own jump numerical Nu compare the following and perform the corresponding operation:
If Nv < Nu − 1, set the Nu = Nv + 1, broadcast hello message and Nu to the neighbor nodes. If Nu ≠ ∞, the node transmission power will be raised to the largest and the node NL list will be empty.
Again after a certain time delay after each node broadcasting notice sending its neighbor nodes report its existence, the purpose is to obtain the node communication coverage expanded new NL list, then each Sink node to send a hello message in networking on a network, with reference to the number of Sink node modulus value [
if Nu/Ns = Nv/Ns,Add the node u’s and v’s id number to the NL list.
if Nu/Ns > Nv/Ns and Nu%Ns = Nv%Ns, Add the node u’s and v’s id number to the PL list.
if Nu /Ns < Nv/Ns and Nu%Ns = Nv%Ns, Add the node u’s and v’s id number to the CL list.
if Nu /Ns= Nv/Ns and Nu%Ns = Nv%Ns, Add the node u’s and v’s id number to the SL list.
The uplink process routing table is shown as
The ω grade in routing table can ensure that there was a fault in the network, the channel adjustment mechanism to fault to connect with the other layer, reach the purpose of rapid, complete data transmission, embodied in the local node transmission data channel adjustment algorithm [
Simulation experiment platform for OMNeT++ of selection will be used in transmission line monitoring wireless sensor network model is defined as shown in
According to the method described in this article, We will use the hierarchical network construction of multimode hierarchical load balance network, which is shown in
In
Combined with the characteristics of the transmission system, the long chain tree network structure is put forward. The recent convergence node of sensor network is easy to form a “funnel”, the multimode hierarchical network is built for load balance. Monitoring sensor network was applied to transmission line which has the advantages, and faces many difficulties, however. There are still some technical problems to be studied, mainly including transmission bandwidth, transmission distance, node power supply and electromagnetic compatibility, network security etc.
This work is supported by National Natural Science Foundation of China (No. 60974125).
LifenLi,HuaiyuZhao, (2015) Power Line Monitoring Data Transmission Using Wireless Sensor Network. Journal of Power and Energy Engineering,03,83-88. doi: 10.4236/jpee.2015.38008