# Force-Based Self-Organizing MANET/FANET with a UAV Swarm
## 1 Introduction
### Using Drones to Deploy MANETs  
With advancements in technology, drones are increasingly being recognized for their potential in supporting MANETs [1]. They present a viable solution for enhancing connectivity, particularly in hard-to-reach or infrastructure-less environments, such as wilderness areas or in the aftermath of a disaster [19] (see Figure 1).  
Given their airborne nature and inherent mobility [20], drones are not hindered by ground obstacles. In addition, they can be equipped with wireless communication devices  
Figure 1: Four screenshots showing a deployed MANET servicing all the clients (the stress is indicated by color, with the continuous spectrum ranging from bright green (where the Link Quality Metric (LQM)\(\rightarrow\)1), over yellow (for a LQM value of \(\approx\)0.5) to red (when LQM\(\rightarrow\)0)). This sequence of screenshots shows the response of a single swarm to successive relocations of the clients.  
and employed as mobile nodes or access points within a MANET. This allows them to adapt and reconfigure the network's topology dynamically, and intentionally and to do so in direct response to changes in user demand or in environmental conditions. The use of drones in MANETs offers several key operational advantages:  
* Flexibility of resource sourcing and maintenance: since the collective of drones (the swarm) is comprised of physically distinct and independently operating devices, the deployment of such a swarm (including the addition and removal of drones during operation) can be very flexible. The operations are the sum of the actions of independent units, which allows for different stakeholders and operators to pool their resources while each maintaining separate responsibility and ownership for the resources they contributed. Especially in cases where large-scale infrastructure, beyond the financial or operational resources of any one party, has been rendered inoperable, this enables smaller parties to come together and collectively solve a problem/provide a service.
* Adaptive network topology [7; 16]: when drones are launched with the express goal of becoming members in a MANET, their movement can be designed to contribute to this goal. Due to this, drones that have no other objective can collaborate with those that do by optimizing their position to improve the overall performance of the MANET. This strengthens the ability of the MANET to respond to changing demand profiles and to client terminal movement.
* Exploiting advantages of aerial positions: purely through their ability to move in 3D space, drones can assume positions that offer advantages due to (a) not being restricted by obstacles on the ground (regarding signal transmission), (b) not being affected by conditions on the ground (with regard to the safety of the device). This does come at the price of increased operational cost (as the flight operations require continuous investment of resources) but a sufficiently large number of drones can offset this at least regarding node availability (by retiring drones that are low on battery and sending them home to re-charge).
* Reactivity and resilience: not only can drones position themselves to optimize the topology, but they can dynamically amend their positioning to ensure desired levels of redundancy. This allows them to establish a topology not only suitable for the current state of affairs but also for potential future conditions.  
It is not all sunshine and rainbows, though. As already hinted at above, there are operational challenges and drawbacks to the use of drones as node-carrying platforms.