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Secure and Efficient Context-Aware Localization of Drones in Urban Scenarios
Sharma, Vishal,Jayakody, Dushantha Nalin K.,You, Ilsun,Kumar, Ravinder,Li, Jun Institute of Electrical and Electronics Engineers 2018 IEEE communications magazine Vol.56 No.4
<P>Drone swarming involves multiple unmanned aerial vehicles (UAVs), which are able to manoeuver autonomously, providing a vast range of surveillance applications such as traffic evaluations, driver monitoring, disaster management, temporary network support, and pedestrian tracking. All these applications are an integral part of urban surveillance. In other words, cooperation between multiple drones can facilitate urban surveillance while being able to provide high-quality 3D visualization of the surroundings. This 3D representation is driven by the initiation of accurate and non-overlapping waypoints. Such efficient localization depends on the type of context and its security validation by the receiving entities. For example, a highly burdened context with negligible security is of limited use. This article presents a novel solution that is capable of securing the context information for sharing 3D waypoints between UAVs. The proposed approach achieves optimal localization through hierarchical context- aware aspect-oriented Petri nets while being powered by a novel drone context-exchange protocol for security validations.</P>
Secure and Energy-Efficient Handover in Fog Networks Using Blockchain-Based DMM
Sharma, Vishal,You, Ilsun,Palmieri, Francesco,Jayakody, Dushantha Nalin K.,Li, Jun IEEE 2018 IEEE communications magazine Vol.56 No.5
<P>Modern fog network architectures, empowered by IoT applications and 5G communications technologies, are characterized by the presence of a huge number of mobile nodes, which undergo frequent handovers, introducing a significant load on the involved network entities. Considering the distributed and flat nature of these architectures, DMM can be the only viable option for efficiently managing handovers in these scenarios. The existing DMM solutions are capable of providing smooth handovers, but lack robustness from the security point of view. Indeed, DMM depends on external mechanisms for handover security and uses a centralized device, which has obvious security and performance implications in flat architectures where hierarchical dependencies can introduce problems. We propose a new DMM schema based on the blockchain, capable of resolving hierarchical security issues without affecting the network layout, and also satisfying fully distributed security requirements with less consumption of energy.</P>
Din Iftikhar Ud,Ullah Waheed,Abbasi Nisar Ahmad,Ullah Sadiq,Shihzad Waleed,Khan Bilawal,Jayakody Dushantha Nalin K. 한국전자파학회 2023 Journal of Electromagnetic Engineering and Science Vol.23 No.2
This article presents a compact ultra-wideband (UWB) circular monopole antenna with a frequency-selective surface (FSS) for gain enhancement. The proposed antenna has a circular patch with circular cuts at the edges and is excited by a microstrip feed. The bottom plane is truncated and further modified by two triangular cuts at the sides and one rectangular cut in the middle to improve the radiation characteristics of the UWB antenna. The antenna is designed on an FR-4 substrate with a thickness of 1.6 mm, a relative permittivity of 4.3, and planner dimensions of 30 mm × 30 mm. To improve the proposed antenna’s gain, an FSS is designed that consists of periodic unit cells of metal printed on the upper layer of an FR-4 substrate with dimensions of 0.11λ × 0.11λ at the lowest operating frequency of 3.3 GHz. The FSS shows a very low transmission coefficient and linearly reducing reflection phase with increasing frequency over a frequency range of 3.3–10.8 GHz. The gain of the proposed antenna is increased from 3 dB to 8.1 dB at 9 GHz by placing the antenna on the FSS. Moreover, the prototype of the proposed antenna is fabricated, and the experimental results are measured, which show close agreements with simulated results. The FSS-based antenna has directional radiation patterns, making it a potential candidate for ground-penetrating radar and UWB applications.