LOCALIZATION SCHEMES FOR UNDERWATER WIRELESS SENSOR NETWORKS: SURVEY

Faiza Al-Salti¹ , N. Alzeidi² and Khaled Day²

¹Department of Computing, Muscat College, Oman

²Department of Computer Science, Sultan Qaboos University, Oman

Abstract 

Underwater Wireless Sensor Networks (UWSNs) enable a variety of applications such as fish farming and water quality monitoring. One of the critical tasks in such networks is localization. Location information can be used in sensor networks for several purposes such as (i) data tagging in which sensed information is not useful for the application unless the location of the sensed information is known, (ii) tracking objects or (iii) multi-hop data transmission in geographic routing protocols. Since GPS does not work well underwater, several localization schemes have been developed for UWSNs. This paper surveys the state-ofthe-art of localization schemes for UWSNs. It describes the existing schemes and classifies them into different categories. Furthermore, the paper discusses some open research issues that need further investigation in this area.

Keywords 

Underwater Wireless Sensor Networks, Localization, Ranging Methods, Positioning, Range-based &Range-free.                  

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SIGNALING PROTOCOLS FOR LOCAL AREA NETWORKS OF DRONES

Prabhu Jyot Singh and Rohan de Silva

School of Engineering and Technology CQ University Sydney, Australia

Abstract 

Unmanned Aerial Vehicles (UAVs) or drones have become extremely popular and are used in various commercial applications. When multiple UAVs communicate and work together, they form a UAV network. A private UAV network or Local Area Network of Drones (LoDs) is a special type of UAV network which has the minimum number of UAVs to carry out a certain task. All UAVs in a LoD use the wireless medium to send and receive the data as well as the control signals. An organization or a single owner will be more interested in this type of network, where they want multiple UAVs to scan an area, communicate with each other, and send all the images and live video streams to a single ground station. The currently available commercial UAVs Can send the video signals to and receive control signals only from their own ground station controllers. However, in an LoD network where UAVs are connected in tandem, the UAVs that are in the middle of the network have to carry the control and video signals of other UAVs. Given the limited processing power and dynamic memory capacity of UAVs, this would increase the queuing delays and performance. In this paper, we study the frame formats of existing control, feedback, and data messages of commercial AR UAVs and propose a new approach to construct the payloads of control and feedback frames that are suitable for an LoDs. We compare the performance of our approach of single control and feedback frame for all UAVs in a LoD branch with that of separate control and feedback frames for each UAV. We calculate and compare the UAV node processing delay in both types of signaling mechanisms and show that the single control and feedback frame signaling has less delay on the average.

Keywords 

UAV communication, Private UAV Network, LANs of Drones, Signaling Frames, Control and feedback singling                     

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ENERGY-EFFICIENT MULTI-HOP ROUTING WITH UNEQUAL CLUSTERING APPROACH FOR WIRELESS SENSOR NETWORKS

Younes El Assari , Samia Al Fallah, Jihane El Aasri, Mounir Arioua and Ahmed El Oualkadi

Laboratory of Information and Communication Technologies, National School of Applied Sciences, Abdelmalek Essaadi University, Tangier, Morocco

Abstract 

The development of an energy-efficient routing protocol, capable of extending the life of the network, is one of the main constraints of wireless sensor networks (WSN). Research studies on WSN routing prove that clustering offers an effective approach to prolong the lifetime of a WSN, particularly when it is combined with multi-hop communication that can reduces energy costs by minimizing the distance between transmitter and receiver. Most clustering algorithms using multi-hop in data transmission encounter the hotspot problem. In this work, an Energy-efficient Multi-hop routing with Unequal Clustering approach (EMUC) is proposed, to create clusters of different sizes, which depend on the distance between the sensor node and the base station. Equilibrate the energy dissipation between the cluster heads is the purpose of this approach by adopting multi-hop communication to relay data to the base station. The implementation of multi-hop mode to transmit data to the base station reduces the energy cost of transmission over long distances. The effectiveness of this approach is validated through performed simulations, which prove that EMUC balances energy consumption between sensor nodes, mitigates the hotspots problem, saves more energy and significantly extends the network lifetime.

Keywords 

Energy-efficient, Hotspot issue, Routing protocols, Unequal clustering, Wireless sensor networks, Multihop communication                      

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