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Gdańsk University of Technology

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Publications from the year 2022

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  • Deep Eutectic Solvents or Eutectic Mixtures? Characterization of Tetrabutylammonium Bromide and Nonanoic Acid Mixtures
    • Andrey Shishov
    • Patrycja Makoś-Chełstowska
    • Andrey Bulatov
    • Vasil Andruch
    2022 Full text JOURNAL OF PHYSICAL CHEMISTRY B

    Deep eutectic solvents have quickly attracted the attention of researchers because they better meet the requirements of green chemistry and thus have the potential to replace conventional hazardous organic solvents in some areas. To better understand the nature of these mixtures, as well as expand the possibilities of their use in different industries, a detailed examination of their physical properties, such as density, viscosity, the nature of the interactions between their constituents, the phase diagrams, depression of their melting point, and interpretation of these results is necessary. In this work, the mixtures of tetrabutylammonium bromide (TBAB) and nonanoic acid (NA) in different molar ratios are theoretically and experimentally investigated by applying a phase diagram constructed on the basis of differential scanning calorimetry measurements and COSMO-RS model. Spectral properties are investigated based on Fourier transform infrared spectroscopy and density functional theory. The observed eutectic point indicates the formation of a DES in the TBAB−NA system in a 1:2 molar ratio. This is due to the presence of hydrogen bonds between the carboxyl group from the NA molecule and the bromine atom from the TBAB molecule. Other eutectic mixtures are most likely the solutions of TBAB in NA, in which hydrogen bonds predominate between acid molecules.

  • Deep learning approach on surface EEG based Brain Computer Interface
    • Łukasz Radzinski
    • Tomasz Kocejko
    2022

    In this work we analysed the application of con-volutional neural networks in motor imagery classification for the Brain Computer Interface (BCI) purposes. To increase the accuracy of classification we proposed the solution that combines the Common Spatial Pattern (CSP) with convolutional network (ConvNet). The electroencephalography (EEG) is one of the modalities we try to use for controlling the prosthetic arm. Therefor in this paper we exploited the subject dependent approach and show results for models trained individually for a particular subject. Although the ConvNets are design to work directly with EEG data, presented approach of joining CSP with ConvNet shows increase in accuracy of movement classification. In average, our approach resulted in ∼80% accuracy.

  • DEEP LEARNING BASED ON X-RAY IMAGING IMPROVES COXARTHROSIS DETECTION
    • Michał Maj
    • Jakub Borkowski
    • Jan Wasilewski
    • Sylwia Hrynowiecka
    • Adrian Kastrau
    • Mariusz Liksza
    • Patryk Jasik
    • Mariusz Treder
    2022

    Objective: The purpose of the study was to create an Artificial Neural Network (ANN) based on X-ray images of the pelvis, as an additional tool to automate and improve the diagnosis of coxarthrosis. The research is focused on joint space narrowing, which is a radiological symptom showing the thinning of the articular cartilage layer, which is translucent to X-rays. It is the first and the most important of the radiological signs of degenerative changes. Material and Methods: As part of the study, 13374 pelvis cases with 26748 X-ray images of the hip joints were collected. All images were cropped and added to the database with the associated annotations created by the team of three orthopaedists. For the test dataset, 20% of random cases were chosen to correspond to statistical degenerative changes types distribution. The classification task was performed in a two-stage process using Convolutional Neural Networks (CNNs). First, the localization model was trained to locate the bounding boxes (width, height, center coordinates) containing the hip joint with its immediate surroundings, which reduced the size of data and hence the computational power needed for classification. Then, cropped images were classified using another CNN, loosely based on CheXNet architecture. Results: The accuracy of the localization model, measured by the intersection over union metric, was more than 94%. Trained ANN correctly classified 87.4% of cases with a 95% confidence interval (95CI) equals 85.6-89.1%. Results of precision of 91.7% (95CI 90.6-92.7%), sensitivity of 93.5% (95CI 92.0-94.8%), and F1 score of 92.6% (95CI 91.5-93.6%) were achieved. Conclusions: Created ANN reached promising accuracy. Combined with the good automated detection of the hip joints, it could potentially aid the fast differentiation of stable and urgently required medical intervention patients. Acknowledgments: We acknowledge partial support from UE within the NCBiR Epionier program (WG-POPC.03.03.00-00-0008/16-00).

  • Deep learning-based waste detection in natural and urban environments
    • Sylwia Majchrowska
    • Agnieszka Mikołajczyk
    • Maria Ferlin
    • Zuzanna Klawikowska
    • Marta A. Plantykow
    • Arkadiusz Kwasigroch
    • Karol Majek
    2022 Full text WASTE MANAGEMENT

    Waste pollution is one of the most significant environmental issues in the modern world. The importance of recycling is well known, both for economic and ecological reasons, and the industry demands high efficiency. Current studies towards automatic waste detection are hardly comparable due to the lack of benchmarks and widely accepted standards regarding the used metrics and data. Those problems are addressed in this article by providing a critical analysis of over ten existing waste datasets and a brief but constructive review of the existing Deep Learning-based waste detection approaches. This article collects and summarizes previous studies and provides the results of authors’ experiments on the presented datasets, all intended to create a first replicable baseline for litter detection. Moreover, new benchmark datasets detect-waste and classify-waste are proposed that are merged collections from the above-mentioned open-source datasets with unified annotations covering all possible waste categories: bio, glass, metal and plastic, non-recyclable, other, paper, and unknown. Finally, a two- stage detector for litter localization and classification is presented. EfficientDet-D2 is used to localize litter, and EfficientNet-B2 to classify the detected waste into seven categories. The classifier is trained in a semi- supervised fashion making the use of unlabeled images. The proposed approach achieves up to 70% of average precision in waste detection and around 75% of classification accuracy on the test dataset. The code and annotations used in the studies are publicly available online1.

  • Defending against Fake VIP in Scant-Transparency Information Systems with QoS Differentiation
    • Jerzy Konorski
    2022 Full text INFORMATION SCIENCES

    In client-server information systems with quality of service (QoS) differentiation, Client may deplete Server’s resources by demanding unduly high QoS level. Such QoS abuse has eluded systematic treatment; known defenses using Client authorization, payments, or service request inspection prior to QoS assignment, are heuristic and environment-specific. We offer a game-theoretic approach on the premise that a service request is occasionally trusted to reduce the inspection cost. We call Fake VIP attack (FVA) a form of QoS abuse that consciously exploits Server’s trust. An FVA strategy instills trust to maximize Client’s utility gained from successful FVAs, whereas a trust strategy maximizes Server’s utility by trading her loss due to successful FVAs against the request inspection cost. We consider a realistic scant-transparency setting where only long-term utilities are observable. Against a probabilistic FVA strategy we design a trust strategy based on double-blind reputation. Assuming a memoryless service request stream we analyze the impact of the request inspection cost and information leakage on the utilities at the Stackelberg equilibrium of the arising game. Experimental comparison with a real-world internally correlated stream is also shown.

  • Deformable model of a butterfly in motion on the example of Attacus atlas
    • Zuzanna Kunicka-kowalska
    • Michał Landowski
    • Krzysztof Sibilski
    2022 Journal of the Mechanical Behavior of Biomedical Materials

    Insect wings can undergo significant chordwise (camber) as well as spanwise (twist) deformation during flapping flight but the effect of these deformations is not well understood. The shape and size of butterfly wings leads to particularly large wing deformations, making them an ideal test case for investigation of these effects. High-speed videogrammetry was used to capture the wing kinematics and deformations. The movements of selected markers on the wings of a living insect was observed. Created characteristics showing the displacement in a three-dimensional coordinate system identified the kinematics and deformations of the butterfly’s wings. These experimental results were then analyzed computationally using a high-fidelity, three-dimensional, unsteady Navier-Stokes flow solver. Computational fluid dynamics (CFD) simulations were carried out on the basis of the wing geometry of the large moth Attacus atlas. Six geometric and structural models of the Attacus atlas butterfly wing with various degrees of simplification were developed. Using these models, Fluid-Structure-Interaction (FSI) simulation studies were performed in the commercial Ansys software environment (Fluent and Mechanical). Computations of the wing beat cycle were carried out, obtaining pressure distributions, streamlines, vortex regions and cumulative force waveforms.

  • Deformacje filtracyjne i ich oddziaływanie na osiadanie podłoża na przykładzie zabytkowego obiektu sakralnego
    • Paweł Popielski
    • Tomasz Majewski
    • Bartosz Bednarz
    • Maciej Niedostatkiewicz
    2022 Full text Materiały Budowlane

    W artykule omówiono studium przypadku wykorzytując dane dotyczzące pęknięć i deformacji w zabytkowym budynku oraz przecieków wody w jego podłozu. Przedstawiono charakterytykę deformacji filyracyjnych gruntu z uwagi na jego rodzaj i przyczynę. Na podstawie danych z monitoringu poziomu wody gruntowej w okolicach obiketu przeanalizowano przecieki i wyznaczono strefy w których przekroczone zostało kryterium inicjacji procesu deformacji filtracyjnych. W pracy przedstawiono również koncepcje rozwiązań projektowych w zakresie zabezpieczenia budynku z uewagi na deformacj filtracyjne gruntu.

  • Degradation of 1,4-dioxane by sono-activated persulfates for water and wastewater treatment applications
    • Shirish H. Sonawane
    • Kirill Fedorov
    • Manoj P Rayaroth
    • Grzegorz Boczkaj
    2022 Full text Water Resources and Industry

    This paper presents a hybrid advanced oxidation process (AOP) based on sonocavitational activation of persulfate (PS) for degradation of 1,4-dioxane during wastewater treatment. Application of sono-cavitation effectively convert PS to radical species demonstrating synergistic effect by increasing the reaction rate and reducing the required energy for activation. It is economically feasible and deployed alternative to the direct thermal activation method. A single and two-stage injection of PS were compared to eliminate self-scavenging effects related to excess of oxidant in system. A GC-MS analysis was used to determine the degradation products of dioxane and to propose the degradation mechanism. The studies revealed that the degradation was significantly enhanced by the addition of PS at molar ratio of oxidant to pollutant 4 with a two-stage injection. Under optimal conditions at US density of 105 W/cm2, dioxane with an initial concentration of 100 mg/L was completely degraded in 120 min.

  • Degradation of tetracycline antibiotic utilizing light driven-activated oxone in the presence of g-C3N4/ZnFe LDH binary heterojunction nanocomposite
    • Reza Darvishi Cheshmeh Soltani
    • Elham Abolhasani
    • Masoumeh Mashayekhi
    • Najla Jorfi
    • Grzegorz Boczkaj
    • Alireza Khataee
    2022 Full text CHEMOSPHERE

    In the present study, a binary heterojunction nanocomposite composed of graphitic carbon nitride (g-C3N4) and Zn/Fe-contained layered double hydroxide (ZnFe LDH) was employed as heterogeneous catalyst for the decomposition of tetracycline (TC) antibiotic utilizing Oxone and UV light irradiation. The sole use of g-C3N4/ZnFe LDH as adsorbent led to the negligible elimination of TC. In addition, the sole use of Oxone or UV (photolysis) and even their combination were not effective enough to degrade the target pollutant, while the combined process of g-C3N4/ZnFe LDH/Oxone/photolysis revealed significantly enhanced (synergistic) degradation of TC (92.4% within 30 min). Indirect detection tests for the identification of free radical species indicated the major role of both hydroxyl (•OH) and sulfate (SO4•−) radicals in the degradation of TC by the g-C3N4/ZnFe LDH/Oxone/photolysis system. The elimination of TC followed a pseudo-first order kinetic model. The complete degradation of TC (degradation efficiency of 100%) was achieved within the reaction time of 25 min when ultrasound (US) was applied as enhancing agent. Furthermore, the results of total organic carbon (TOC) analysis were used to exhibit progress in the mineralization of the pollutant. The bioassay results indicated the decreased toxicity of the process effluent toward microbial population of Escherichia coli after the treatment.

  • Demolition of the cereal elevator building located in the conservation protection zone in the aspect of technical, functional-utility and economic conditions
    • Maciej Niedostatkiewicz
    • Tomasz Majewski
    2022 Full text Inżynieria Bezpieczeństwa Obiektów Antropogenicznych

    The paper presents a description of the technical condition of the Grain Elevator building situated on the port quay, which after many years of operation has been decommissioned. The immediate reason for the cessation of operation was the change in the use profile of the port quay, which caused the handling of other goods at the quay than the bulk materials originally stored in Elewator Zbożowy. The work contains a detailed analysis of the technical condition of the building, also taking into account the functional and utility aspect as well as the economics of renovation works. The article showed that despite the location of the building in the conservation protection zone, the optimal solution was the demolition of Grain Elevator and its reconstruction of a new warehouse facility with parameters adapted to the current needs and target handling capacity of the port quay

  • Dependence of Housing Real Estate Prices on Inflation as One of the Most Important Factors: Poland’s Case
    • Oleksandr Melnychenko
    • Tetiana Osadcha
    • Anatoliy Kovalyov
    • Valerii Matskul
    2022 Full text Real Estate Management and Valuation

    The study aimed to examine the impact of inflation on the real estate market using Polish panel data for the last 13 years. It is based on a panel model, where price changes of one square meter of housing are determined as a function in changes of inflation, the central bank's base rate, dwellings built, as well as new mortgage loans. The quarterly dynamics of the average price of 1 square meter of housing in Poland’s eight largest cities in the 2009-2021 period was studied. This price was modeled and predicted using one of the Box-Jenkins time series models: the Holt-Winter model of exponential smoothing with a damped trend. The forecasting results showed a small (up to 4%) relative error in comparison with the actual data. In addition, the moment (2017) of the price trend change was found. Therefore, piecewise linear regressions with high regression coefficients were used when modeling the impact of inflation changes on the real estate market indicators under consideration. The results obtained provide valuable insight into the relationship of real estate market indicators, allowing consumers to predict available options and make decisions in accordance with their preferences.

  • DEPO: A dynamic energy‐performance optimizer tool for automatic power capping for energy efficient high‐performance computing
    • Adam Krzywaniak
    • Paweł Czarnul
    • Jerzy Proficz
    2022 SOFTWARE-PRACTICE & EXPERIENCE

    In the article we propose an automatic power capping software tool DEPO that allows one to perform runtime optimization of performance and energy related metrics. For an assumed application model with an initialization phase followed by a running phase with uniform compute and memory intensity, the tool performs automatic tuning engaging one of the two exploration algorithms—linear search (LS) and golden section search (GSS), finds a power cap optimizing a given metric and sets it for the remaining computations. The considered metrics include energy (E), energy-delay sum, energy-delay product. We present experimental results obtained for a set of benchmarks that differ in compute and memory intensity—parallel custom built OpenMP implementations of: numerical integration, heat distribution simulation (HEAT), fast Fourier transform (FFT), and additionally NAS parallel benchmarks: CG, MG, BT, SP, and LU. Tests were performed using multi-core CPUs that are representatives of modern servers and the desktop family: 2 Intel Xeon E5-2670 v3 CPU (Haswell-EP) and Intel i7-9700K CPU (Coffee Lake). The results show that our approach enabled considerable improvements for the tested metrics, for example, for HEAT and Coffee Lake we minimized energy by 50% at the cost of a 15% increase in execution time (LS), for FFT energy was minimized by 40% at a 25.5% increase in execution time (GSS), for SP and Haswell energy was minimized by 25% at the cost of an 18.5% time increase and for Coffee Lake energy was decreased by 56% with a 12% time increase.

  • Design and Analysis of Artificial Neural Network (ANN) Models for Achieving Self-Sustainability in Sanitation
    • Mahesh Ganesapillai
    • Aritro Sinha
    • Rishabh Mehta
    • Aditya Tiwari
    • Vijayalakshmi Chellappa
    • Jakub Drewnowski
    2022 Full text Applied Sciences-Basel

    The present study investigates the potential of using fecal ash as an adsorbent and demonstrates a self-sustaining, optimized approach for urea recovery from wastewater streams. Fecal ash was prepared by heating synthetic feces to 500 °C and then processing it as an adsorbent for urea adsorption from synthetic urine. Since this adsorption approach based on fecal ash is a promising alternative for wastewater treatment, it increases the process’ self- sustainability. Adsorption experiments with varying fecal ash loadings, initial urine concentrations, and adsorption temperatures were conducted, and the acquired data were applied to determine the adsorption kinetics. These three process parameters and their interactions served as the input vectors for the artificial neural network model, with the percentage urea adsorption onto fecal ash serving as the output. The Levenberg–Marquardt (TRAINLM) and Bayesian regularization (TRAINBR) techniques with mean square error (MSE) were trained and tested for predicting percentage adsorption. TRAINBR was demonstrated in our study to be an ideal match for improving urea adsorption, with an accuracy of R = 0.9982 and a convergence time of seven seconds. The ideal conditions for maximum urea adsorption were determined to be a high starting concentration of 13.5 g.L−1; a low temperature of 30 °C, and a loading of 1.0 g of adsorbent. For urea, the improved settings resulted in maximum adsorption of 92.8%.

  • Design and Characterization of a Planar Structure Wideband Millimeter-Wave Antenna with Wide Beamwidth for Wearable off-body Communication Applications
    • Ullah Ubaid
    • Magdalena Kozieł
    • Anna Pietrenko-Dąbrowska
    2022 IEEE Antennas and Wireless Propagation Letters

    This letter presents the design of a planar single-layer wideband antenna featuring wide beamwidth has well as high and stable in-band gain. The proposed antenna is a planar monopole fed by a bottom-grounded coplanar waveguide to realize wide beamwidth in both the xz- and yz-planes. Simultaneous optimization of all adjustable antenna parameters, carried out at the full-wave electromagnetic simulation level. The constructive interference of the radiated fields resulting in impedance bandwidth of more than 2 GHz, from 27 GHz to 29 GHz. Along with a stable realized gain (>11 dBi) in the operating frequency band. The proposed antenna maintains a directional radiation pattern in the broadside direction. Merging the radiated modes of the slots and the parasitic patch elements also extends the antenna beamwidth to roughly ±35o with respect to the broadside direction. Following a detailed theoretical analysis, the antenna is validated numerically and experimentally, both in the free space and on a human volunteer chest and arm.

  • Design and Implementation of a Dual-band Filtering Wil-kinson Power Divider Using Coupled T-shaped Dual-band Resonators
    • Sobhan Roshani
    • Bartosz Kozieł
    • Saeed Roshani
    • Faeeh Sadat Mehr
    • Stanisław Szczepański
    2022 Full text ENERGIES

    The paper introduces a novel structure of a dual-band filtering Wilkinson power divider (WPD). Its essential component is a dual-band bandpass filter (BPF), implemented using coupling lines and two T-shaped resonators. The BPF is incorporated into the divider structure to suppress the unwanted harmonics within the circuit. The latter is achieved owing to a wide stopband of the filter. The deigned dual-band WPD can suppress third unwanted harmonics in both channels with high levels of attenuation. The designed dual-band WPD operates at 2.6 GHz and 3.3 GHz with the return loss of 22.1 dB and 22.3 dB at the operating frequencies. Furthermore, the inser-tion loss and isolation are 0.3 dB and 20.2 dB at 2.6 GHz, and 0.9 dB and 24.5 dB at 3.3 GHz. The analysis and simulation results are corroborated by the measurements of the fabricated divider prototype. The competitive performance of the proposed circuit is also demonstrated through comparisons with state-of-the-art divider circuits from the literature.

  • Design and Microwave-Assisted Synthesis of TiO2-Lanthanides Systems and Evaluation of Photocatalytic Activity under UV-LED Light Irradiation
    • Adam Kubiak
    • Anna Grzegórska
    • Joanna Zembrzuska
    • Anna Zielińska-Jurek
    • Katarzyna Siwińska-Ciesielczyk
    • Marcin Janczarek
    • Piotr Krawczyk
    • Teofil Jesionowski
    2022 Full text Catalysts

    The TiO2-Eu and TiO2-La systems were successfully synthesized using the microwave method. Based on the results of X-ray diffraction analysis, it was found that regardless of the analyzed systems, two crystal structures were noted for the obtained samples: anatase and rutile. The analysis, such as XPS and EDS, proved that the doped lanthanum and europium nano-particles are present only on the TiO2 surface without disturbing the crystal lattice. In the synthesized systems, there were no significant changes in the bandgap energy. Moreover, all the obtained systems were characterized by high thermal stability. One of the key objectives of the work, and a scientific novelty, was the introduction of UV-LED lamps into the metronidazole photo-oxidation pathway. The results of the photo-oxidation study showed that the obtained TiO2 systems doped with selected lanthanides (Eu or La) show high efficiency in the removal of metronidazole, and at the same consuming nearly 10 times less electricity compared to conventional UV lamps (high-pressure mercury lamp). Liquid-chromatography mass-spectrometry (LC-MS) analysis of an intermediate solution showed the presence of fragments of the degraded molecule by m/z 114, 83, and 60, prompting the formulation of a plausible photodegradation pathway for metronidazole.

  • Design and Optimization of a Compact Planar Radiator for UWB Applications and Beyond
    • Michał Czyż
    • Jan Olencki
    • Adrian Bekasiewicz
    2022 Full text

    A compact monopole antenna for ultra-wideband (UWB) and beyond applications has been proposed. The radiator is based on the monopole topology. The super-wideband behavior has been achieved using a combination of spline-based modifications applied to the driven element, as well as utilization of a tapered feed and a slot-modified ground plane. The electrical performance of the structure has been tuned using a numerical optimization algorithm. The proposed design features reflection below the level of –10 dB within 2.8 GHz to 30 GHz range, as well as a footprint of only 404 mm2. The proposed structure has been compared in terms of bandwidth and size with the state-of-the-art antennas from the literature. The numerical results are supported by measurements of the fabricated antenna prototype.

  • Design and Optimization of Metamaterial-Based Dual-Band 28/38 GHz 5G MIMO Antenna with Modified Ground for Isolation and Bandwidth Improvement
    • Bashar Esmail
    • Sławomir Kozieł
    2022 IEEE Antennas and Wireless Propagation Letters

    This letter presents a high-isolation dual-band multiple-input multiple-output (MIMO) antenna based on the ground plane modification and optimized metamaterials (MMs) for 5G millimeter-wave applications. The antenna is a monopole providing a dual-band response at 5G 28/38 bands with a small physical size (4.8 × 2.9 × 0.762 mm3, excluding the feeding line). The MIMO consists of two symmetric radiating elements arranged adjacently with the mutual coupling of −19 dB and −17 dB at 28 and 38 GHz, respectively. Reducing the ground length enhances the isolation to 34.6 dB at 28 GHz, whereas embedding the MMs diminishes the coupling to −47 dB at 38 GHz. The trust-region gradient-based search algorithm is employed to optimize the MM structure dimensions and to enhance the isolation at 38 GHz. The MMs also contribute to the enhancement of bandwidth from 1.6 GHz to 1.7 GHz at 28 GHz (27.1–28.8 GHz) and from 2.75 GHz to 3.7 GHz at 38 GHz (35.2–38.9 GHz). The proposed system is capable of covering both 28/38 bands with low profile structure, high isolation, low envelope correlation coefficient (ECC) (< 0.210−4), and high diversity gain (DG) (> 9.99 dB). These properties demonstrate the system applicability for 5G millimeter-wave cellular communications.

  • Design of a Coplanar Waveguide-Fed Wideband Compact-Size Circularly Polarized Antenna and polarization-sense alteration
    • Ullah Ubaid
    • Sławomir Kozieł
    • Anna Pietrenko-Dąbrowska
    • Ismail Mabrouk
    2022 WIRELESS NETWORKS

    This paper presents the design and validation of a geometrically simple circularly polarized(CP) structure featuring flat gain in the sub-6 GHz 5th generation spectrum. The proposed structure is based on coplanar-waveguide-fed, modified wide slot etched in the ground plane. For generating CP waves, the coplanar ground planes are designed with slight asymmetry in both the horizontal and vertical directions. Furthermore, the ground plane at the back is modified to create an additional current component. The antenna is realized with a compact footprint of 0.36λo × 0.28λo (or 0.12o ). The operating frequency is from 2.5 to 6 GHz, which covers all the bands in the sub-6 GHz spectrum of the 5th generation technology. The impedance bandwidth of the antenna is in the range of 2.45 to 8 GHz and the axial ratio (AR) bandwidth is from 2.5 to 6 GHz, corresponding to more than 82% of relative bandwidth. The peak realized gain is 4 dBic, which is relatively high for a bidirectional wideband structure, and very stable throughout the entire operating band with a variation of ± 0.35 dBic. Unlike the design available in the literature (with asymmetrical ground planes), the proposed antenna has a consistent radiation pattern with a minor beam tilt. The design is fully optimized before prototyping and experimental validation. From the application viewpoint, the proposed antenna has the potential to be used in integrated systems. Moreover, a simple method for altering the sense of CP from right-hand CP (RHCP) to left-hand CP (LHCP) and vice versa is studied. This technique is useful for implementation of polarization diversity in the multiple-input-multipleoutput (MIMO) environment.

  • Design of Cost-Efficient Optical Fronthaul for 5G/6G Networks: An Optimization Perspective
    • Abdulhalim Fayad
    • Tibor Cinkler
    • Jacek Rak
    • Manish Jha
    2022 Full text SENSORS

    Currently, 5G and the forthcoming 6G mobile communication systems are the most promising cellular generations expected to beat the growing hunger for bandwidth and enable the fully connected world presented by the Internet of Everything (IoE). The cloud radio access network (CRAN) has been proposed as a promising architecture for meeting the needs and goals of 5G/6G (5G and beyond) networks. Nevertheless, the provisioning of cost-efficient connections between a large number of remote radio heads (RRHs) in the cell sites and the baseband unit (BBU) pool in the central location, known as the fronthaul, has emerged as a new challenge. Many wired and wireless solutions have been proposed to address this bottleneck. Specifically, optical technologies presented by passive optical networks (PONs) are introduced as the best suitable solution for 5G and beyond network fronthaul due to their properties of providing high capacity and low latency connections. We considered time and wavelength division multiplexed passive optical networks (TWDM-PONs) as a fronthaul for 5G and beyond. Taking that into consideration, in this paper, we propose an integer linear program (ILP) that results in the optimal optical fronthaul deployment while minimizing the total cost of 5G and beyond instances. However, for larger network instances, solving the ILP problem becomes unscalable and time-consuming. To address that, we developed two heuristic-based algorithms (the K-means clustering algorithm and the one based on the genetic algorithm—GA). We evaluated the suitability of our proposed ILP and heuristic algorithms in simulations by utilizing them to plan different network instances (dense and sparse).