# Drone Deployment Algorithms for Effective Communication Establishment in Disaster Affected Areas
## 1 Introduction  
The human race has always shown immense potential to manage and cope with natural disasters. As humans, we have developed various techniques to prevent and mitigate these life-threatening disasters. Setting up a communication infrastructure is widely discussed among such techniques, as normal means of communication might be devastated during disasters [1]. One of the most critical parts of disaster response is effective information exchange between information sources, emergency managers, and those impacted by the disaster event. During disaster events, the terrestrial communications infrastructure, such as mobile phone networks, TV networks, and radio networks, are frequently affected by the disaster impacts. This situation has a considerable impact on all preparedness, response, and recovery processes in disaster conditions [2]. Hence, there is always a need to maintain the entire disaster affected region under communication coverage throughout the rescue operations. The communication between disaster management organizations, the general public, and other actors is a critical and fundamental factor in providing a quick and opportune response to all aspects of the disaster event. Many practical experiences show the importance of communication during a disaster [3]. One such case is the _Pettimudi Landslide_[4] that occurred in India on 6 August 2020. The disaster resulted in the swapping of communication lines and blockage of roads due to the uprooting of trees. This made it challenging for the local search groups to contact the base station. It was reported in the leading dailies that rescue groups had to stay near dead bodies for nearly three hours [5]. They needed to wait for other teams to arrive with avehicle or wireless device before they were able to share messages. The rescue operations were effective only after the restoration of mobile towers. Another case is the _Sichuan Earthquake_[6] that occurred in China on 12 May 2008. During the disaster, telecommunication systems were affected. The Chinese government activated the use of the national communications satellite network to recover communication services in all affected areas and support other solution implementations for different types of data exchange between the entities in charge of disaster management. The importance of communication during a disaster can be seen in other events as well. Recent examples include Typhoon Faxai in 2019 in Chiba, Japan [7] and bush fires of New South Wales in 2019-2020 [8]. In the former case, the damage mainly happened to the roofs of buildings, and prompt damage assessment was able to quickly facilitate disaster insurance relief. The latter case required aerial monitoring of areas in order to understand the status and severity of the bush fires. Drones are increasingly becoming a viable alternative to conventional cellular infrastructure in disaster-struck regions thanks to their low cost and availability [9]. Their easy availability and low weight make them potential candidates as communication support in any terrain [10]. An example of such a communication network establishment is shown in Figure 1. Drones can easily be deployed to the affected region from one or more base stations, although performance in terms of flight time due to battery power restrictions, the number of drones required, and terrain constraints all remain matters of concern [11]. This paper considers the idea of deploying drones to restore the communication system in a post-disaster area. As proposed here, a swarm of drones carrying network receptors is deployed in the disaster struck location. The drones can be deployed quickly and conveniently for temporary coverage until more permanent solutions are deployed, allowing recovery operations to continue smoothly. Using this method, the mobile phone network is restored and people can use their mobile phones to notify the concerned authorities. This enables fast establishment of reliable communications in any environment.