Research On Energy Efficiency And Energy Balance In Wireless Distributed Networks

At present,the popularity of mobile phones and wearable devices has brought about a surge in the demand for large bandwidth for large data services (such as video,etc.).At the same time,there are many problems in the current communication network.For example,although the wired network can guarantee the bandwidth,it is not conducive to the portability of the equipment;and the WiFi network uses the Industrial,Scientific and Medical (ISM) unlicensed frequency band,which causes the channel capacity to be too small and coverage is limited;5G network unsaturated coverage brings communication blind spots and user Quality of Service (QoS) degradation;the existing network structure is complex and bloated,with a wide range of network elements,and network upgrade difficulties caused by incompatibility between different networks;the network structure is rigid,unable to adapt to or introduce new upper-layer applications (such as network slicing services) and so on.The above problems are mainly due to the use of wired and single-hop technologies.The wireless distributed network based on multi-hop communication has the characteristics of flexible deployment,survivability,and high efficiency,which makes up for the shortcomings of the above-mentioned single-hop technology,and has attracted more and more attention from the industry.However,the wireless distributed network itself has many problems.For example,unlike wired multi-hop networks,where the topology is relatively stable,wireless distributed networks have the problem of uncertain topology caused by the uncertain node coverage radius;rapid topology changes and excessive routing overhead (flooding) caused by node movement;Due to the different attributes of the nodes (geographical location,remaining power and signal transmission power),and the differences in the network functions of the nodes in the network (participating in forwarding or not),the energy consumption of each node is different.In addition to the above problems in the network transmission process,there are problems with rigid network structures in wireless distributed networks,such as upgrade and maintenance difficulties,security issues,and so on.Aiming at the problems of low energy efficiency and flooding caused by the uncertainty of node coverage in wireless distributed networks,as well as the uneven energy consumption caused by the location of different nodes in the network,this paper adopts convex optimization theory,graph theory,and penetration theory and other mathematical methods to promote the evolution,deployment and implementation of wireless distributed networks for cutting-edge exploration.The main research results and contributions of this paper are as follows:1.Research on optimal transmission distance based on path lossAiming at the problem of low energy efficiency in routing and data transmission caused by the uncertainty of node coverage in wireless distributed networks,this paper studies the optimal hop distance of nodes in one-dimensional space,and proposes an optimal coverage radius theory based on the hop-by-hop routing protocol.Theoretical analysis and simulation results show that under the path loss model and a given Signal Noise Ratio (SNR),there is an optimal hop distance.When the hop distance of each hop is close to the optimal hop distance,energy consumption the smallest.Second,this article discusses the scenario where nodes are randomly distributed in two-dimensional space.The simulation results show that when the density of nodes in the network is large enough and the coverage radius of the nodes is slightly larger than the optimal hop distance,the total energy consumption of system communication is the lowest.The analysis shows that the greater the density of nodes in the network,the closer the coverage radius of the optimal node is to the optimal hop distance.2.Research on flooding based on Percolation theoryAiming at the flooding problem in the wireless distributed network,this paper proposes and verifies a new ring method of routing and forwarding area limitation.Redefine the proximity zone and relay zone through the Ring algorithm to change the definition of neighbor nodes,avoid the situation where two neighboring nodes forward the same route request message to each other,and solve traditional routing methods such as Ad Hoc On-Demand Distance Vector Routing (AODV),etc.,has the problem of excessive forwarding of routing request messages,which improves routing efficiency.At the same time,through the ring algorithm,the relay area is limited to the optimal transmission distance,so each hop in the data transmission process is close to the optimal hop distance,which improves the data transmission efficiency.Finally,because the ring algorithm can make the network sparser and reduce the routing success rate,this paper uses percolation theory (PT) to evaluate the routing success rate of the ring algorithm and provide a reference for parameter settings.The simulation results show that,compared with the traditional circular coverage method,the Ring algorithm can reduce the number of routing request message forwarding by about 50% while ensuring the routing success rate and improving the energy efficiency of data transmission.3.Research on energy balance and energy hole problemAccording to the network structure,the wireless distributed network can be divided into a homogeneous ad hoc network and a wireless sensor network (WSN) with sink nodes,both of which have the problem of energy holes.Aiming at the energy hole problem in wireless ad hoc networks,this paper proposes and verifies a cross-layer energy balance and control strategy.This strategy combines the optimal coverage radius and location information to solve the energy hole problem and improve network capacity.Simulation results show that the proposed method outperforms existing protocols in terms of the number of surviving nodes,network capacity,routing failure and energy balance.Aiming at the energy hole problem in WSN,this paper uses the optimal hop distance theory to adjust the coverage and transmit power of the sensor according to the distance between the sensor and the sink node to alleviate the energy hole problem,by reducing the energy of the inner node consume and increase the energy consumption of peripheral nodes to achieve the goal of energy consumption balance.Simulation results show that the proposed algorithm can greatly improve the lifetime and energy efficiency of WSN.4.Research on wireless sensor network based on software define networkAiming at the difficulties of configuration,upgrade and maintenance(control) and energy holes caused by the rigid network structure of traditional WSN,this paper proposes an energy hole mitigation algorithm based on SDN+WSN architecture.This algorithm solves the problem of difficult configuration after deployment of traditional WSN,and combines the global view characteristics of SDN.Through the sensor residual energy feedback mechanism and the node coverage and transmit power adjustment algorithm,it solves the energy hole problem in WSN and improves WSN's performance.The simulation results show that the proposed method has good performance in terms of the number of surviving nodes,network capacity and remaining energy.