Analyses of WSN/UAV network configuration influences on 2.4 GHz IEEE 802.15.4 signal strength

The presence of wireless sensor networks and their appliance in monitoring the different types of systems is growing in recent years. Considering the importance of a variety of monitoring systems in the open outdoor environments, such as agriculture, traffic monitoring, etc., the application of Wireless Sensor Networks (WSNs) with the integration of Unmanned Aerial Vehicles (UAVs) is important as well. Those networks can be used as support for monitoring the target systems, with the extensive data exchange between UAVs and clusters of fixed wireless sensors deployed in the wide area. In such systems, the planning of the deployment of sensor nodes gives a good starting point for ensuring the effectiveness of the data communications, good area coverage, and cost-effective solutions. When planning the interaction of UAVs and wireless sensor nodes, the mobility of the UAVs, as well as the network configuration and their influence on the signal quality, should be taken into concern. The good planning of wireless sensor nodes can increase the coverage of the system and it can decrease implementation costs as well. This paper has investigated the influence of UAV mobility as well as the network configuration on IEEE 802.15.4 network performance and signal quality. Presented analyses show that there is a clear difference in the influence of various wireless sensor network parameters on the received signal strength (RSSI) at the receiver side. In all four scenarios, the distance between the sensor nodes and UAV has the highest influence on RSSI, with the values ranging from 0.50 to 0.57 in scenarios 1, 3, and 4, and a value of 0.37 for scenario 2. The correlation of two parameters (drone height and elevation) is the same for both scenarios when the real distance is between 400 and 500m, while the drone height influence is slightly higher compared to elevation for scenarios with real distances up to 400m, 0.24 and 0.34 compared to 0.16 and 0.22.