The WSN are used for the collection of the data from the environment in the IOT based smart agriculture systems. The WSN constitute a challenging factor in collection and analysis of the data from the drones, due to the resource scarcity. Clustering can aid in managing the nodes in the sensor networks. The clustering process requires a large amount of energy in determining the most efficient node to be selected as a cluster head. The lifetime of the network is dependent on the energy consumption during the cluster head selection and data transmission process. The chapter proposes a cluster head (CH) selection and routing approach using weight-based cost function for the IOT based smart agriculture system. The nodes in the sensor network are clustered into a number of clusters using the k-medoids clustering. The optimal path for the data transmission towards the base station is obtained using the weighted cost function using the parameters trust value, residual energy and hop count. The performance of the existing approach is validated analytically.
Top1. Introduction
Wireless sensor networks are considered to gain more research interest in today’s time due to the significant advancement in the field of wireless communication scenarios, microelectronic technologies and sensing devices. WSN is categorized as a collection of scattered sensor nodes having limited energy, processing and communication capabilities. In combination with internet of things (IOT) technology, the sensor network finds its application in numerous applications such as healthcare, structural monitoring and different surveillance operations. However, the efficiency of the sensor network is usually restricted due to the limited source of energy (Mahmood et al., 2020) (Pal, Yadav, & Karnwal, 2020).
The WSN are also proving helpful in the task of remote sensing which is extensively used in the area of precision agriculture. The precision agriculture system consists of sensors, actuators and unmanned aerial vehicles. The sensors are deployed in the agriculture area to measure the trend and/or variations. The precision agriculture system found the WSN in the tasks of monitoring and tracking applications like environmental parameters monitoring such as temperature, pressure, soil moisture etc.
The efficiency of the network protocol is largely dependent on the extent of coverage of the target region and is often considered as the quality-of-service related parameter. The point/target/area is said to be covered by a sensor node, only if it lies within the sensing range of the sensor node. The sensing range of the sensor nodes is considered as the circular region and the sensor node is generally located at the center of the region. The direct communication between the sensor node and the base station is usually considered as the energy consuming task, so the network is organized into multiple levels using the clustering techniques. At each level, there is a CH, which performs the aggregation on the data collected from the sensor nodes. The data is transmitted using the multiple relay nodes from the CH towards the base station. The remote sensing in the agriculture system is done with the help of drone. The drone communicates directly through the CH at the different levels. The approaches which consider the clustering as well as routing the sensed data towards the base station in an energy efficient manner is considered to be great significance.
1.1 WSN in Precision Agriculture
The precision agriculture systems can be significantly aided by the use of Wireless sensor network. The application areas of usage of the WSN are as shown in Figure 1. WSN may be utilized in the interconnection of sensing units for the real time detection and monitoring of different parameters such as temperature, humidity, soil moisture etc. The IOT based smart agriculture system can assist the farmers in having the proximate knowledge about the environmental parameters, crop health conditions and the resource usage knowledge, thus these systems are gaining huge attention of the research community.
Figure 1. Application areas of IOT and WSN
The IOT based smart agriculture system is considered to be divided into three layers as: user interface layer, IOT layer and the sensing layer. The organization of these layers is as shown in Figure 2. The user interface layer consists of the interface through which the user can interact with the systems and take appropriate decisions. The IOT layer comprises of the interconnection units which can provide data communication between the different layers. The sensing layer consists of the number of sensing units, which can collect the data about the environmental parameters.
Figure 2. Components of IOT based smart agriculture system