Fog/edge computing has been proposed to be integrated with Internet of Things (IoT) to enable computing services devices deployed at network edge, aiming to improve the user’s experience and resilience of the services in case of failures. With the advantage of distributed architecture and close to end-users, fog/edge computing can provide faster response and greater quality of service for IoT applications. Thus, fog/edge computing-based IoT becomes future infrastructure on IoT development. To develop fog/edge computing-based IoT infrastructure, the architecture, enabling techniques, and issues related to IoT should be investigated first, and then the integration of fog/edge computing and IoT should be explored. To this end, this paper conducts a comprehensive overview of IoT with respect to system architecture, enabling technologies, security and privacy issues, and present the integration of fog/edge computing and IoT, and applications. Particularly, this paper first explores the relationship between cyber-physical systems and IoT, both of which play important roles in realizing an intelligent cyber-physical world. Then, existing architectures, enabling technologies, and security and privacy issues in IoT are presented to enhance the understanding of the state of the art IoT development. To investigate the fog/edge computing-based IoT, this paper also investigate the relationship between IoT and fog/edge computing, and discuss issues in fog/edge computing-based IoT. Finally, several applications, including the smart grid, smart transportation, and smart cities, are presented to demonstrate how fog/edge computing-based IoT to be implemented in real-world applications.

A Survey on Internet of Things: Architecture, Enabling Technologies, Security and Privacy, and Applications

Course Description This is an advanced course in which we explore the field of Statistical Optics. Topics covered include such subjects as the statistical properties of natural (thermal) and laser light, spatial and temporal coherence, effects of partial coherence on optical imaging instruments, effects on imaging due to randomly inhomogeneous media, and a statistical treatment of the detection of light. Development of this more comprehensive model of the behavior of light draws upon the use of tools traditionally available to the electrical engineer, such as linear system theory and the theory of stochastic processes.

http://ieeexplore.ieee.org/iel5/3/23094/01073023.pdf

Statistical optics

Metasurfaces: From microwaves to visible

Optical Waveguide Theory

This letter presents a new metamaterial-based waveguide technology referred to as ridge gap waveguides. The main advantages of the ridge gap waveguides compared to hollow waveguides are that they are planar and much cheaper to manufacture, in particular at high frequencies such as for millimeter and sub- millimeter waves. The latter is due to the fact that there are no mechanical joints across which electric currents must float. The gap waveguides have lower losses than microstrip lines, and they are completely shielded by metal so no additional packaging is needed, in contrast to the severe packaging problems associated with microstrip circuits. The gap waveguides are realized in a narrow gap between two parallel metal plates by using a texture or multilayer structure on one of the surfaces. The waves follow metal ridges in the textured surface. All wave propagation in other directions is prohibited (in cutoff) by realizing a high surface impedance (ideally a perfect magnetic conductor) in the textured surface at both sides of all ridges. Thereby, cavity resonances do not appear either within the band of operation. The present letter introduces the gap waveguide and presents some initial simulated results.

Local Metamaterial-Based Waveguides in Gaps Between Parallel Metal Plates

Recent advances in the development of self-seeded WDM-PON communication systems employing modulation averaging are presented. Optical transmitter containing extended-cavity resonator with modulation-averaging reflector at the remote node improves the link margin and allows for a wider range of bias conditions at the transmitter. The developed modulation-averaging reflector is a passive optical device and therefore the remote nodes in our proposed WDM-PON system remain passive. Optimization of WDM-PON system components, in particular optimization of modulation-averaging reflector, is discussed in the paper.

Self-seeded WDM-PON for next generation broadband access networks

This paper gives a closer insight to novel optical fibers by ap plying specialized numerical analysis approaches. First we have described a newly developed algorithm based on the spectral domain approach, which is employed in the analysis of multilayer optical fibers with circular symm etry. It computes the Green’s functions of the considered fiber and locates the appropriate poles, which correspond to the actual propagating modes of the fiber. Through further analysis of the poles it is possible to obtain inform ation about modal fields, attenuation, bending losses and dispersion properties for all modes present in fibers with ve ry complicated refractive index profile. Furthermore, an approach for the analysis of novel types of fibers belongin g to the so-called Photonic Crystal Fibers family is presented. Since the considered fibers can contain variou s inclusions in the core or the cladding structure, the analysis is in this case based on the modal decomposition of t he electric field in spatial domain. In both analysis cases the obtained results were compared to the previously p b ished or where possible measured results, showing very good agreement.

/pdf/specialty-optical-fibers-analysis-and-characterization-4q6oul15m8.pdf

Specialty Optical Fibers: Analysis and Characterization

Implantable bioelectronic devices predominantly use wireless links for communication and/or power transfer. When considering transmitting implanted antennas, electromagnetic radiation through biological media is highly attenuated, and previous work has shown that the in-body path loss can be separated into three parts: the losses incurred by the propagating fields, the reflections at media interfaces, and the coupling of the antenna reactive near field and the lossy body. The first two are unavoidable, but a careful antenna design should minimize the near-field losses. Thus, quantifying the near-field losses of implanted antennas is useful in selecting the antenna topology for preliminary design. The aim of this paper is to present a simplified model of an implanted antenna that provides closed-form approximate expressions to estimate EM radiation from the implant. In particular, we extend the expressions for the reactive near-field losses to both deep and shallow implants, by taking into account the implantation depth. Additionally, the proposed approximate method is verified by comparing the results obtained with the full-wave simulations in the case of a miniature implanted antenna, and with both simulated and measured results from two practical examples found in the literature.

https://doi.org/10.1109/ojap.2023.3276686

Analytic Approximation of In-Body Path Loss for Implanted Antennas

The use of higher symmetries in periodic structures has made possible the development of new designs of microwave components with enhanced properties. Significant potential of this new way of making periodic structures can also be applied in design of electromagnetic band-gap (EBG) structures. This can simplify the manufacturing of components in gap waveguide technology, but at the same time it is necessary to respect some limitations and challenging design aspects. In this work, we will discuss the properties of EBG glide-symmetrical holey structures and how to apply them in the realization of gap waveguide technology.

Higher symmetries in holey structures applied to gap waveguide technology: fundamentals and considerations

: 1) Formulation of the problem. 2) Modeling single circular stacked-patch antenna on spherical structures. 3) Modeling patch arrays on spherical structures. 4) Development of experimental model.

/pdf/analysis-of-conformal-stacked-patch-arrays-4ud35u2y22.pdf

Zvonimir Sipus

Papers

Self-seeded WDM-PON for next generation broadband access networks

Specialty Optical Fibers: Analysis and Characterization

Analytic Approximation of In-Body Path Loss for Implanted Antennas

Higher symmetries in holey structures applied to gap waveguide technology: fundamentals and considerations

Analysis of Conformal Stacked-Patch Arrays