Q2. What have the authors stated for future works in "Uav assistance paradigm: state-of-the-art in applications and challenges" ?
Indeed, there are many challenging issues and shortcomings in each UAVassisted proposal, which are in need of further investigation and most of the time they are left as future works or barely looked at by the authors. This allows us to outline future opportunities for researchers who want to embark on a deep study in the UAV assistance paradigm. As future work, the authors are currently planning to investigate deeply the concept of visible light communication and its deployment in UAV networks.
Q3. Why do UAVs require the shortest paths to perform their given missions?
Due to the time flight restriction and movement constraint, UAVs require the smoothest and shortest paths to perform their given missions.
Q4. Why are UAVs considered as the solution to provide emergency connectivity?
due to their flexibility and adjustable mobility, UAVs are considered as the best solution to provide emergency connectivity to rescue teams, to victims, and to control servers.
Q5. What are the main challenges during the design of a routing protocol?
The specific mobility models and the different areas of movements of UAVs and terrestrial nodes constitute the major challenges during the design of a routing protocol.
Q6. Why are UAVs deployed to collect information about the area of interest?
Due to the complexity of surrounding obstructions and bad weathers that permanently prevent the LoS between UAVs and the monitored targets, ground sensors are deployed to collect information about the area of interest and transmit them to the closest UAV.
Q7. What are the challenges that need to be solved when UAVs act as relays on top?
when UAVs act as relays on top of VANETs, many challenges, such as reducing the induced overhead, regulating the energy consumption among UAVs, and defining the appropriate mobility models, need to be solved.
Q8. What is the importance of synchronizing the wake-up and sleep schedule of ground sensors?
The wake-up and sleep schedule of ground sensors needs to be synchronized according to the positions of the UAVcollector and not with exchanging messages in order to reduce the overhead.
Q9. What are the main issues that have to be considered when deploying multiple BSs?
in the case when UAV-BSs are deployed, other important issues have to be considered, such as the high mobility of both GUs and UAVs, the energy constraint of UAVs and GUs, the vulnerable frequency when UAV-BSs, GUs, and BSs communicate at the same time, the scalability of the network when new UAVs or GUs join it.
Q10. What are the problems that hinder the transition of data packets between communicating nodes?
Among the problems that hinder the transition of data packets between communicating nodes are the introduced additional delays, the extra overhead, the energy constraints of UAVs and ground nodes, and a lot of exchange of messages in the case when a global knowledge of the topology is required.
Q11. What are the main issues that may be raised when using one of these techniques?
When adopting one of these techniques, various issues may be raised, such as the degradation of network throughput, the high aerial interference, the restricted coverage, and the negligence of surrounding environments and physical constraints.
Q12. What constraints have to be considered before defining a planned trajectory?
Several constraints have to be considered before defining a planned trajectory, such as the continuous connectivity, the collisions, the energy restriction, and the air corridors [86].
Q13. How can you use a UAV to help a ground network?
embedded with wireless interfaces and navigation equipment, it is very easy to organize UAVs in an ad hoc network or multiUAV network communicating with each other and assisting ground networks.
Q14. How can the problem of interference be mitigated?
As a result, the problem of interference can be mitigated by diversifying frequency spectrum or by enabling efficient coordination among UAVs, thus requiring a deep study to be put on the field.
Q15. What are the used techniques to perform UAV-WSN monitoring?
a number of lessons are learned during their study of this kind of applications, which can be summarized as follows: • Remote sensing using communications and surveillance using a camera are the most used techniques to perform UAV-WSN monitoring.
Q16. What are the three categories of flying entities that can serve terrestrial networks?
As depicted in Fig. 2, there are three different categories of flying entities that can serve terrestrial networks: (i) LowAltitude UAVs (LAUs), (ii) High-Altitude UAVs (HAUs), and (iii) Satellites.
Q17. What are the tasks that are used to plan a path for a UGV?
The low-level control includes several tasks, such as mapping, path planning for both UGVs and UAVs, landing UAVs onto UGVs, and picking up lightweight UGVs using UAVs.
Q18. What is the way to reduce the time and cost to develop applications using distributed UAVs?
Multiple UAVs/Mobile Multiple groundnodes Urban area Reducing the time and cost to develop applications using distributed UAVs Demonstrated high performance with the broker layer.