To address the constraints on the efficiency of emergency search and rescue caused by the limited observation of ground emergency communication support vehicles and the insufficient battery life of drones in scenarios such as weak signal coverage areas and no-man's lands, an edge drone search and rescue strategy based on the LoRa wireless sensor network is proposed. A thermal imaging sensing and acquisition node is designed and mounted on the edge drone to form a LoRa star communication network together with the gateway drone. An adaptive dynamic time window node allocation algorithm is designed to effectively allocate the number of edge drones according to the search and rescue area, enabling the efficient transmission of sensing data. The research results show that this method can acquire the life and environmental information in the remote search and rescue area in real time, and the message acquisition ability within the network is improved by 1.14% compared with the previous method, which can provide efficient information support for on-site search and rescue decision-making.