The 1st International Conference on Computational Engineering and Intelligent Systems

Computational engineering, artificial intelligence and smart systems constitute a hot multidisciplinary topic contrasting computer science, engineering and applied mathematics that created a variety of fascinating intelligent systems. Computational engineering encloses fundamental engineering and science blended with the advanced knowledge of mathematics, algorithms and computer languages. It is concerned with the modeling and simulation of complex systems and data processing methods. Computing and artificial intelligence lead to smart systems that are advanced machines designed to fulfill certain specifications. This proceedings book is a collection of papers presented at the first International Conference on Computational Engineering and Intelligent Systems (ICCEIS2021), held online in the period December 10-12, 2021. The collection offers a wide scope of engineering topics, including smart grids, intelligent control, artificial intelligence, optimization, microelectronics and telecommunication systems. The contributions included in this book are of high quality, present details concerning the topics in a succinct way, and can be used as excellent reference and support for readers regarding the field of computational engineering, artificial intelligence and smart system

Journal of Telecommunications and Information Technology, 2007, nr 1

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Integrated Filters and Couplers for Next Generation Wireless Tranceivers

The main focus of this thesis is to investigate the critical nonlinear distortion issues affecting RF/Microwave components such as power amplifiers (PA) and develop new and improved solutions that will improve efficiency and linearity of next generation RF/Microwave mobile wireless communication systems. This research involves evaluating the nonlinear distortions in PA for different analog and digital signals which have been a major concern. The second harmonic injection technique is explored and used to effectively suppress nonlinear distortions. This method consists of simultaneously feeding back the second harmonics at the output of the power amplifier (PA) into the input of the PA. Simulated and measured results show improved linearity results. However, for increasing frequency bandwidth, the suppression abilities reduced which is a limitation for 4G LTE and 5G networks that require larger bandwidth (above 5 MHz). This thesis explores creative ways to deal with this major drawback. The injection technique was modified with the aid of a well-designed band-stop filter. The compact narrowband notch filter designed was able to suppress nonlinear distortions very effectively when used before the PA. The notch filter is also integrated in the injection technique for LTE carrier aggregation (CA) with multiple carriers and significant improvement in nonlinear distortion performance was observed. This thesis also considers maximizing efficiency alongside with improved linearity performance. To improve on the efficiency performance of the PA, the balanced PA configuration was investigated. However, another major challenge was that the couplers used in this configuration are very large in size at the desired operating frequency. In this thesis, this problem was solved by designing a compact branch line coupler. The novel coupler was simulated, fabricated and measured with performance comparable to its conventional equivalent and the coupler achieved substantial size reduction over others. The coupler is implemented in the balanced PA configuration giving improved input and output matching abilities. The proposed balanced PA is also implemented in 4G LTE and 5G wireless transmitters. This thesis provides simulation and measured results for all balanced PA cases with substantial efficiency and linearity improvements observed even for higher bandwidths (above 5 MHz). Additionally, the coupler is successfully integrated with rectifiers for improved energy harvesting performance and gave improved RF-dc conversion efficienc

Rectenna circuits for RF energy harvesting in miniature DBS devices.

 Development of an optimum rectenna for radio frequency energy harvesting in miniature head-mountable deep brain stimulation (DBS) devices. The designed miniature rectenna can operate a DBS device without battery for murine preclinical research. The battery-less operation of the device eliminates battery related difficulties

Détection de changement par fusion d'images de télédétection de résolutions et modalités différentes

La détection de changements dans une scène est l’un des problèmes les plus complexes en télédétection. Il s’agit de détecter des modifications survenues dans une zone géographique donnée par comparaison d’images de cette zone acquises à différents instants. La comparaison est facilitée lorsque les images sont issues du même type de capteur c’est-à-dire correspondent à la même modalité (le plus souvent optique multi-bandes) et possèdent des résolutions spatiales et spectrales identiques. Les techniques de détection de changements non supervisées sont, pour la plupart, conçues spécifiquement pour ce scénario. Il est, dans ce cas, possible de comparer directement les images en calculant la différence de pixels homologues, c’est-à-dire correspondant au même emplacement au sol. Cependant, dans certains cas spécifiques tels que les situations d’urgence, les missions ponctuelles, la défense et la sécurité, il peut s’avérer nécessaire d’exploiter des images de modalités et de résolutions différentes. Cette hétérogénéité dans les images traitées introduit des problèmes supplémentaires pour la mise en œuvre de la détection de changements. Ces problèmes ne sont pas traités par la plupart des méthodes de l’état de l’art. Lorsque la modalité est identique mais les résolutions différentes, il est possible de se ramener au scénario favorable en appliquant des prétraitements tels que des opérations de rééchantillonnage destinées à atteindre les mêmes résolutions spatiales et spectrales. Néanmoins, ces prétraitements peuvent conduire à une perte d’informations pertinentes pour la détection de changements. En particulier, ils sont appliqués indépendamment sur les deux images et donc ne tiennent pas compte des relations fortes existant entre les deux images. L’objectif de cette thèse est de développer des méthodes de détection de changements qui exploitent au mieux l’information contenue dans une paire d’images observées, sans condition sur leur modalité et leurs résolutions spatiale et spectrale. Les restrictions classiquement imposées dans l’état de l’art sont levées grâce à une approche utilisant la fusion des deux images observées. La première stratégie proposée s’applique au cas d’images de modalités identiques mais de résolutions différentes. Elle se décompose en trois étapes. La première étape consiste à fusionner les deux images observées ce qui conduit à une image de la scène à haute résolution portant l’information des changements éventuels. La deuxième étape réalise la prédiction de deux images non observées possédant des résolutions identiques à celles des images observées par dégradation spatiale et spectrale de l’image fusionnée. Enfin, la troisième étape consiste en une détection de changements classique entre images observées et prédites de mêmes résolutions. Une deuxième stratégie modélise les images observées comme des versions dégradées de deux images non observées caractérisées par des résolutions spectrales et spatiales identiques et élevées. Elle met en œuvre une étape de fusion robuste qui exploite un a priori de parcimonie des changements observés. Enfin, le principe de la fusion est étendu à des images de modalités différentes. Dans ce cas où les pixels ne sont pas directement comparables, car correspondant à des grandeurs physiques différentes, la comparaison est réalisée dans un domaine transformé. Les deux images sont représentées par des combinaisons linéaires parcimonieuses des éléments de deux dictionnaires couplés, appris à partir des données. La détection de changements est réalisée à partir de l’estimation d’un code couplé sous condition de parcimonie spatiale de la différence des codes estimés pour chaque image. L’expérimentation de ces différentes méthodes, conduite sur des changements simulés de manière réaliste ou sur des changements réels, démontre les avantages des méthodes développées et plus généralement de l’apport de la fusion pour la détection de changement

Intelligent Circuits and Systems

ICICS-2020 is the third conference initiated by the School of Electronics and Electrical Engineering at Lovely Professional University that explored recent innovations of researchers working for the development of smart and green technologies in the fields of Energy, Electronics, Communications, Computers, and Control. ICICS provides innovators to identify new opportunities for the social and economic benefits of society.　 This conference bridges the gap between academics and R&D institutions, social visionaries, and experts from all strata of society to present their ongoing research activities and foster research relations between them. It provides opportunities for the exchange of new ideas, applications, and experiences in the field of smart technologies and finding global partners for future collaboration. The ICICS-2020 was conducted in two broad categories, Intelligent Circuits & Intelligent Systems and Emerging Technologies in Electrical Engineering

EM-driven miniaturization of high-frequency structures through constrained optimization

The trends afoot for miniaturization of high-frequency electronic devices require integration of active and passive high-frequency circuit elements within a single system. This high level of accomplishment not only calls for a cutting-edge integration technology but also necessitates accommodation of the corresponding circuit components within a restricted space in applications such as implantable devices, internet of things (IoT), or 5G communication systems. At the same time, size reduction does not remain the only demand. The performance requirements of the abovementioned systems form a conjugate demand to that of the size reduction, yet with a contrasting nature. A compromise can be achieved through constrained numerical optimization, in which two kinds of constrains may exist: equality and inequality ones. Still, the high cost of electromagnetic-based (EM-based) constraint evaluations remains an obstruction. This issue can be partly mitigated by implicit constraint handling using the penalty function approach. Nevertheless, securing its performance requires expensive guess-work-based identification of the optimum setup of the penalty coefficients. An additional challenge lies in allocating the design within or in the vicinity of a thin feasible region corresponding to equality constraints. Furthermore, multimodal nature of constrained miniaturization problems leads to initial design dependency of the optimization results. Regardless of the constraint type and the corresponding treatment techniques, the computational expenses of the optimization-based size reduction persist as a main challenge. This thesis attempts to address the abovementioned issues specifically pertaining to optimization-driven miniaturization of high frequency structures by developing relevant algorithms in a proper sequence. The first proposed approach with automated adjustment of the penalty functions is based on the concept of sufficient constraint violation improvement, thereby eliminating the costly initial trial-and-error stage for the identification of the optimum setup of the penalty factors. Another introduced approach, i.e., correction-based treatment of the equality constraints alleviates the difficulty of allocating the design within a thin feasible region where designs satisfying the equality constraints reside. The next developed technique allows for global size reduction of high-frequency components. This approach not only eliminates the aforementioned multimodality issues, but also accelerates the overall global optimization process by constructing a dimensionality-reduced surrogate model over a pre-identified feasible region as compared to the complete parameter search space. Further to the latter, an optimization framework employing multi-resolution EM-model management has been proposed to address the high cost issue. The said technique provides nearly 50 percent average acceleration of the optimization-based miniaturization process. The proposed technique pivots upon a newly-defined concept of model-fidelity control based on a combination of algorithmic metrics, namely convergence status and constraint violation level. Numerical validation of the abovementioned algorithms has also been provided using an extensive set of high-frequency benchmark structures. To the best of the author´s knowledge, the presented study is the first investigation of this kind in the literature and can be considered a contribution to the state of the art of automated high-frequency design and miniaturization

Recent Advances in Signal Processing

The signal processing task is a very critical issue in the majority of new technological inventions and challenges in a variety of applications in both science and engineering fields. Classical signal processing techniques have largely worked with mathematical models that are linear, local, stationary, and Gaussian. They have always favored closed-form tractability over real-world accuracy. These constraints were imposed by the lack of powerful computing tools. During the last few decades, signal processing theories, developments, and applications have matured rapidly and now include tools from many areas of mathematics, computer science, physics, and engineering. This book is targeted primarily toward both students and researchers who want to be exposed to a wide variety of signal processing techniques and algorithms. It includes 27 chapters that can be categorized into five different areas depending on the application at hand. These five categories are ordered to address image processing, speech processing, communication systems, time-series analysis, and educational packages respectively. The book has the advantage of providing a collection of applications that are completely independent and self-contained; thus, the interested reader can choose any chapter and skip to another without losing continuity

Wireless Links for Telecare and Telemedicine Applications using Compact Body-Worn Antennas.

PhDThis thesis concerns the design of body-centric wireless communications for short-range indoor Telecare/Telemedicine applications. Such communications are starting to be used to convey key, relatively low data-rate body-sensor data wirelessly between on-body sensor node(s) located on potentially mobile clients/patients and fixed off-body Access Point(s). From the outset, key practical considerations/constraints were assumed; in particular that, wherever possible, existing components (including antennas) and established protocols would be employed. This approach should enable existing manufacturers of mobile wireless components to rapidly adapt to the potential Telecare/Telemedicine market segment with minimum R&D capital outlay. In addition, maximum user convenience of the on-body nodes has been taken into account to ensure that they are readily accepted and hence actually used. As anticipated, using existing mobile antennas (designed for nominally free space use) in close proximity to the human body poses several limitations. These are quantified here for a particular candidate commercial device. In the process, however, a novel unanticipated effect of the nearby body was also discovered; namely that the body completely depolarises the (otherwise reasonably polarised) antenna patterns. A potential physical explanation for this effect is identified and evaluated by means of analysis based on a modified Geometric Optics approach. The result of this analysis agrees with those simulated and measured here to remarkable accuracy. The thesis then presents several multi-antenna schemes to overcome these severe limitations and identifies that best suited to the indoor Telecare/Telecommunication application here. Simulations at the Physical Layer are reported with this optimum Wireless Links for Telecare and Telemedicine using Compact Body-Worn Antennas 8 single-input multiple-output (SIMO) antenna scheme for a typical indoor scenario. These quantify the overall system performance when such measures are adopted, demonstrating that it is adequate in this role. Finally, promising techniques are suggested for Future Work which could afford further significant system improvements for future upgrades of the solution presented here. In particular, the use of metamaterial techniques are indicated which could substantially reduce on-body transmit powers currently required. This would give highly desirable increases in battery lifetimes for the mobile battery powered on-body nodes.Engineering and Physical Science Research Council (EPSRC

Performance Analysis For Wireless G (IEEE 802.11 G) And Wireless N (IEEE 802.11 N) In Outdoor Environment

This paper described an analysis the different capabilities and limitation of both IEEE technologies that has been utilized for data transmission directed to mobile device. In this work, we have compared an IEEE 802.11/g/n outdoor environment to know what technology is better. the comparison consider on coverage area (mobility), through put and measuring the interferences. The work presented here is to help the researchers to select the best technology depending of their deploying case, and investigate the best variant for outdoor. The tool used is Iperf software which is to measure the data transmission performance of IEEE 802.11n and IEEE 802.11g