A Cross-Layer Design for Data Collecting of the UAV-Wireless Sensor Network System

There are advantages to retrieve information from the Wireless Sensor Network (WSN) for UAVs (Unmanned Aerial Vehicles). However, the UAV-WSN system has some differences with conventional WSN system. So it is important to design an appropriate scheme to control the transmission in a UAV-WSN system. In this paper we proposed a protocol called A-OAloha (Adaptive-Opportunistic Aloha) for UAV-UAV-WSN system to guarantee its efficiency. This protocol is based on a cross-layer design and is designed with the consideration of the distribution of the successful sensors, energy consumption and the transmission efficiency. For the distribution of the successful sensors, we design a mechanism based on the priority to make the distribution more uniform and the priority could be adaptively changed. For the consideration of energy-efficiency we choose to use the method that make the sensors go into sleep when they do not need to send data until a beacon signal from the UAV is received to transmit data. For the transmission efficiency we added a communication stage in every interval based on the O-Aloha scheme to enlarge the throughput under an acceptable system Bit Error Rate (BER).