Research On Energy-Efficient Multi-Chain Routing Algorithm Based On Hybrid Antennas

Wireless sensor network?WSN?is a distributed sensor network.It is composed of a large number of wireless sensor network which can perceive the external world in a self-organized and multi hop mode.Using different type of sensors,WSN can detect all kinds of information including temperature,humidity,light intensity,magnetic field,soil composition,and so on.Thus,WSN can be widely used in many fields,such as military applications,health,environment and agriculture,smart home,etc.The agriculture of our country has been develop ing rapidly since the reform and opening up.However,China's agricultural economy is still far behind western modern agriculture no matter in speed,scale,or benefits.Under this situation,the government has been committed to promoting the construction of agricultural modernization.Farmland area is generally large,so it is not convenient by means of artificial monitoring,and the use of emerging wireless sensor network technology in farmland monitoring is of great significance for the realization of agricultural modernization.The routing protocol is one of the key and difficult points in the research of wireless sensor networks.It is responsible for determining the transmission path of the data from the source node to the destination node.A suitable routing algorithm can balance the network energy consumption,improve the data transmission efficiency and prolong the network lifetime.Due to the limited energy of sensor nodes,the routing algorithm in WSN has its own characteristics compared with traditional routing algorithms.Most of the traditional wireless sensor networks are equipped with omnidirectional antennas.Although the price of omnidirectional antennas is cheap and they are easy to install,their communication range is small and energy consumption is big,which limit the network scale and cause extra energy consumption in the useless direction.In this paper,the use of directional antennas in WSN reduced the energy consumption and expanded the network size.In addition,the multi-chain structure was used to avoid long link and reduce the delay.This design of energy efficient algorithm in WSN is researched in this paper.Considering the energy of nodes in large-area wireless sensor networks drain rapidly for long-distance wireless communications,we propose EEMC?Energy-Efficient Multi-Chain Routing?in this paper,a protocol that is based on hybrid networks which contain directional antennas and omnidirectional antennas.In EEMC,a threshold of distance is defined to avoid forming long link a nd sensors are grouped into several short chains.O ne sensor is elected as a leader based on the residual energy and position in every chain and this node sends data to Base-Station?BS?after collecting the information of nodes in the chain.Sensors can send data to each other through omnidirectional antennas while they communicate with BS through directional antennas.Simulation results show that EEMC can save and balance the network energy consumption and its performance is better than other algorithms especially in large WSN.In scene 3 whose WSN scale is larger?400 nodes are randomly distributed in the area of 400m×400m?,compared to PEGASIS,LEACH,COSEN and CCS,the lifetime of EEMC increase by 104.6%,70.6%and 31.6%.Meanwhile,the lifetime of LEACH is only 33 round.When it comes to stable period,EEMC reaches 674 rounds while other algorithms are less than 26 rounds.When the network run to the 600^{t h} round,the total residual energy of EEMC is 294.0%,165.6%and80.2%higher than that of PEGASIS,COSEN and CCS respectively.All the nodes die at the414^th round in LEAC H,however the last node die at the 1232^nd round in EEMC.In terms of network delay,EEMC is about 50%of PEGASIS.The network delay of LEAC H,COSEN and CCS is about 23%of PEGASIS.