{"results":[{"id":"arxiv_2602.15207","title":"Near-Infrared and Telecommunication-Wavelength Photon-Pair Source in Optical Fiber","authors":[{"name":"Keshav Kapoor"},{"name":"Dong Beom Kim"},{"name":"Kriti Shetty"},{"name":"Virginia O. Lorenz"}],"abstract":"We present a photon-pair source in commercially available optical fiber that produces paired photons at telecommunication and near-infrared (NIR) wavelengths. The highly nondegenerate pairs are 700 nm apart: one in the 1500 nm E- and S-band telecommunication range and the other in the 830 nm NIR range. The high non-degeneracy means the photon pairs are far-detuned from Raman noise, resulting in a high coincidence-to-accidental ratio even while operating at room temperature. The source produces two spectrally and spatially distinct phase-matched processes with low spectral cross-talk, distinct transverse spatial modes in the NIR, and a single fundamental spatial mode in the telecommunication range. The source's room-temperature operation, off-the-shelf materials, and multiplexing potential make it promising for deployment in quantum networks.","source":"arXiv","year":2026,"language":"en","subjects":["quant-ph","physics.optics"],"url":"https://arxiv.org/abs/2602.15207","pdf_url":"https://arxiv.org/pdf/2602.15207","is_open_access":true,"published_at":"2026-02-16T21:36:46Z","score":70},{"id":"arxiv_2501.04356","title":"Sustainability in Telecommunication Networks and Key Value Indicators: a Survey","authors":[{"name":"Lucia Pintor"},{"name":"Luigi Atzori"},{"name":"Antonio Iera"}],"abstract":"Telecommunication technologies are important enablers for both digital and ecological transitions. By offering digital alternatives to traditional modes of transportation and communication, they help reduce carbon footprints while improving access to fundamental services. Particularly in rural and remote areas, telecommunications facilitate access to education, healthcare, and employment, helping to bridge the digital divide. Additionally, telecommunications can promote sustainability by supporting renewable energy usage, gender equality, and circular economies. However, defining the role of telecommunications in sustainability remains complex due to the historical focus on performance rather than long-term societal goals. Given the significance of this theme, this paper aims to provide the reader with a deeper look at the concept of sustainability within the telecommunications sector by examining relevant initiatives and projects. It reviews the major approaches for measuring sustainability and outlines practical approaches for implementing these assessments. Furthermore, the paper explores the proposed network architectures that incorporate Key Value Indicators and discusses major technologies in this area, such as Network Digital Twins and Intent-Based Networking. Through this analysis, the paper aims to contribute to creating sustainable telecommunication networks and broader industries.","source":"arXiv","year":2025,"language":"en","subjects":["cs.NI"],"doi":"10.1016/j.comnet.2025.111466","url":"https://arxiv.org/abs/2501.04356","pdf_url":"https://arxiv.org/pdf/2501.04356","is_open_access":true,"published_at":"2025-01-08T08:54:22Z","score":69},{"id":"doaj_10.1049/mia2.70071","title":"Slow‐Wave HMSIW‐SSPP Leaky‐Wave Antenna With Phase‐Shift Asymmetric Coupling for Continuous Beam Scanning","authors":[{"name":"Yiming Zhang"},{"name":"Yuxi Liu"},{"name":"Sailing He"}],"abstract":"ABSTRACT A compact leaky‐wave antenna (LWA) with innovative phase‐shift asymmetric coupling for continuous beam scanning is presented. The antenna utilises a slow‐wave half‐mode substrate integrated waveguide with spoof surface plasmon polaritons (SW‐HMSIW‐SSPP) transmission line structure to achieve ultra‐compact dimensions in both longitudinal and lateral directions. The radiation characteristic is achieved using sinusoidal modulation on the SSPP structure. To enable continuous beam scanning through broadside, a novel and simple phase‐shift asymmetric coupling method is developed by placing sinusoidally modulated patches with π/2 phase shift on the metallised blind via‐hole arrays. This approach effectively suppresses the open stopband (OSB) and enables continuous beam scanning from backward to forward directions without radiation degradation at broadside. A prototype of the proposed LWA is fabricated and characterised. The measured results demonstrate that the antenna with 12 unit‐cells operates over a wide frequency range from 14.3 to 20.5 GHz with continuous beam scanning from −40° to +30°, while maintaining an ultra‐compact aperture of only 6.67 λ0 × 0.27 λ0.","source":"DOAJ","year":2025,"language":"","subjects":["Telecommunication","Electricity and magnetism"],"doi":"10.1049/mia2.70071","url":"https://doi.org/10.1049/mia2.70071","is_open_access":true,"published_at":"","score":69},{"id":"arxiv_2406.02325","title":"Technical Language Processing for Telecommunications Specifications","authors":[{"name":"Felipe A. Rodriguez Y."}],"abstract":"Large Language Models (LLMs) are continuously being applied in a more diverse set of contexts. At their current state, however, even state-of-the-art LLMs such as Generative Pre-Trained Transformer 4 (GTP-4) have challenges when extracting information from real-world technical documentation without a heavy preprocessing. One such area with real-world technical documentation is telecommunications engineering, which could greatly benefit from domain-specific LLMs. The unique format and overall structure of telecommunications internal specifications differs greatly from standard English and thus it is evident that the application of out-of-the-box Natural Language Processing (NLP) tools is not a viable option. In this article, we outline the limitations of out-of-the-box NLP tools for processing technical information generated by telecommunications experts, and expand the concept of Technical Language Processing (TLP) to the telecommunication domain. Additionally, we explore the effect of domain-specific LLMs in the work of Specification Engineers, emphasizing the potential benefits of adopting domain-specific LLMs to speed up the training of experts in different telecommunications fields.","source":"arXiv","year":2024,"language":"en","subjects":["cs.CL","cs.AI"],"url":"https://arxiv.org/abs/2406.02325","pdf_url":"https://arxiv.org/pdf/2406.02325","is_open_access":true,"published_at":"2024-06-04T13:57:22Z","score":68},{"id":"arxiv_2407.03358","title":"The Radical Pair Mechanism Cannot Explain Telecommunication Frequency Effects on Reactive Oxygen Species","authors":[{"name":"Owaiss Talbi"},{"name":"Hadi Zadeh-Haghighi"},{"name":"Christoph Simon"}],"abstract":"In order to investigate whether the radical pair mechanism (RPM) can explain the effects of telecommunication frequency radiation on reactive oxygen species production, we modelled the effects of oscillating magnetic fields on radical pair systems. Our analysis indicates that the RPM cannot account for the biological effects observed under exposure to telecommunication frequencies due to negligible effects under low-amplitude conditions used in experimental setups. Observable effects on radical pairs at these frequencies would require hyperfine coupling constants that are precisely fine-tuned to large values that far exceed those naturally occurring within biological systems. We conclude that some other mechanism must be responsible for the effects of telecommunication frequency fields in biological systems.","source":"arXiv","year":2024,"language":"en","subjects":["physics.bio-ph","physics.chem-ph","quant-ph"],"url":"https://arxiv.org/abs/2407.03358","pdf_url":"https://arxiv.org/pdf/2407.03358","is_open_access":true,"published_at":"2024-06-23T12:35:57Z","score":68},{"id":"doaj_10.3390/app131910712","title":"The Development of a Secure Internet Protocol (IP) Network Based on Asterisk Private Branch Exchange (PBX)","authors":[{"name":"Mubarak Yakubova"},{"name":"Olga Manankova"},{"name":"Assel Mukasheva"},{"name":"Alimzhan Baikenov"},{"name":"Tansaule Serikov"}],"abstract":"The research problem described in this article is related to the security of an IP network that is set up between two cities using hosting. The network is used for transmitting telephone traffic between servers located in Germany and the Netherlands. The concern is that with the increasing adoption of IP telephony worldwide, the network might be vulnerable to hacking and unauthorized access, posing a threat to the privacy and security of the transmitted information. This article proposes a solution to address the security concerns of the IP network. After conducting an experiment and establishing a connection between the two servers using the WireShark sniffer, a dump of real traffic between the servers was obtained. Upon analysis, a vulnerability in the network was identified, which could potentially be exploited by malicious actors. To enhance the security of the network, this article suggests the implementation of the Transport Layer Security (TLS) protocol. TLS is a cryptographic protocol that provides secure communication over a computer network, ensuring data confidentiality and integrity during transmission. Integrating TLS into the network infrastructure, will protect the telephone traffic and prevent unauthorized access and eavesdropping.","source":"DOAJ","year":2023,"language":"","subjects":["Technology","Engineering (General). Civil engineering (General)","Biology (General)","Physics","Chemistry"],"doi":"10.3390/app131910712","url":"https://www.mdpi.com/2076-3417/13/19/10712","is_open_access":true,"published_at":"","score":67},{"id":"arxiv_2206.03276","title":"Oxford-style Debates in Telecommunication and Computer Science Education","authors":[{"name":"Marcin Niemiec"}],"abstract":"Oxford-style debating is a well-known tool in social sciences. Such formal discussions on particular topics are widely used by historians and sociologists. However, when we try to go beyond standard thinking, it turns out that Oxford-style debating can be a great educational tool in telecommunication and computer science. This article presents this unusual method of education at technical universities and in the IT industry, and describes its features and challenges. Best practices and examples of debating are provided, taking into account emerging topics in telecommunications and computer science, such as cybersecurity. The article also contains feedback from IT engineers who participated in Oxford-style debates. All this aims to encourage this form of education in telecommunication and computer science.","source":"arXiv","year":2022,"language":"en","subjects":["cs.CY"],"url":"https://arxiv.org/abs/2206.03276","pdf_url":"https://arxiv.org/pdf/2206.03276","is_open_access":true,"published_at":"2022-06-03T10:42:31Z","score":66},{"id":"arxiv_2204.03736","title":"Generation of Highly Pure Single-Photon State at Telecommunication Wavelength","authors":[{"name":"Akito Kawasaki"},{"name":"Kan Takase"},{"name":"Takefumi Nomura"},{"name":"Sigehito Miki"},{"name":"Hirotaka Terai"},{"name":"Masahiro Yabuno"},{"name":"Fumihiro China"},{"name":"Warit Asavanant"},{"name":"Mamoru Endo"},{"name":"Jun-ichi Yoshikawa"},{"name":"Akira Furusawa"}],"abstract":"Telecommunication wavelength with well-developed optical communication technologies and low losses in the waveguide are advantageous for quantum applications. However, an experimental generation of non-classical states called non-Gaussian states at the telecommunication wavelength is still underdeveloped. Here, we generate highly-pure-single-photon states, one of the most primitive non-Gaussian states, by using a heralding scheme with an optical parametric oscillator and a superconducting nano-strip photon detector. The Wigner negativity, the indicator of non-classicality, of the generated single photon state is $-0.228\\pm0.004$, corresponded to $85.1\\pm0.7\\%$ of single photon and the best record of the minimum value at all wavelengths. The quantum-optics-technology we establish can be easily applied to the generation of various types of quantum states, opening up the possibility of continuous-variable-quantum-information processing at telecommunication wavelengths.","source":"arXiv","year":2022,"language":"en","subjects":["quant-ph"],"doi":"10.1364/OE.460583","url":"https://arxiv.org/abs/2204.03736","pdf_url":"https://arxiv.org/pdf/2204.03736","is_open_access":true,"published_at":"2022-04-07T21:11:48Z","score":66},{"id":"doaj_10.1049/mia2.12215","title":"A six‐port network based on substrate integrated waveguide coupler with metal strips","authors":[{"name":"Xiaojun Hu"},{"name":"Feng Xu"}],"abstract":"Abstract In this study, a novel coupling structure based on half‐mode substrate‐integrated waveguide (HMSIW) is proposed with a small size and broad bandwidth. The HMSIW coupler is realised by connecting their equivalent magnetic walls with metal strips, which avoids exposing the semi‐enclosed magnetic walls outside. Hence, it has greater anti‐interference capability than the existing HMSIW couplers. The directional coupling principle is introduced by analysing the proposed single connecting strip coupler. In order to lower return loss and higher isolation, a 3 dB directional coupler working from 10.8 to 16.8 GHz is designed with two connecting strips. Finally, a six‐port circuit is achieved by utilising this compact 3 dB directional coupler. Furthermore, a broadband HMSIW power divider is optimised to satisfy the performance of this six‐port circuit. The proposed coupler with metal strips helps to increase bandwidth and reduce size, which makes it more applicable to demanding systems with complex requirements such as detecting and transceiver systems. The 3 dB coupler and six‐port circuit are fabricated and measured. The measured results are in accordance with the simulated data.","source":"DOAJ","year":2022,"language":"","subjects":["Telecommunication","Electricity and magnetism"],"doi":"10.1049/mia2.12215","url":"https://doi.org/10.1049/mia2.12215","is_open_access":true,"published_at":"","score":66},{"id":"doaj_10.1109/ACCESS.2022.3206009","title":"Context Aware Evapotranspiration (ETs) for Saline Soils Reclamation","authors":[{"name":"Arfat Ahmad Khan"},{"name":"Muhammad Asif Nauman"},{"name":"Rab Nawaz Bashir"},{"name":"Rashid Jahangir"},{"name":"Roobaea Alroobaea"},{"name":"Ahmed Binmahfoudh"},{"name":"Majed Alsafyani"},{"name":"Chitapong Wechtaisong"}],"abstract":"Accurate Evapotranspiration for saline soils (ETs) is important as well as challenging for the reclamation of saline soils through an effective leaching process. Evapotranspiration (ET) by FAO-56 Penman-Monteith standard method is complex, especially for saline soils. Moreover, existing studies focus on the use of the Internet of Things (IoT) and machine learning-enabled smart and precision irrigation water recommendation systems along with the ET estimation by limited parameters. The ETs for saline soils are also equally important for the reclamation of saline soils, which is ignored by the existing literature. The study proposed IoT and machine leaching-based architecture of context-aware monthly ETs estimations for saline soil reclamation with the effective leaching process. The IoT-enabled crop field contexts in terms of crop field temperature, soil salinity, and irrigation water salinity are used as input features to the Long Short-Term Memory (LSTM) and ensembled LSTM models for monthly ETs predictions. The performance of the proposed solution is observed in terms of the accuracy of the machine learning models along with the comparison against the FAO-56 PM-based standard method. The implementation of the proposed solution reveals that the ensembled LSTM-based approach for ETs is more accurate as compared to the LSTM model with accuracies of 92 and 90\u0026#x0025; for the training and validation datasets, respectively. The predictions made by the ensembled LSTM are more in line with the FAO-56 PM-based method with a Pearson correlation of 0.916 as compared to LSTM models. The implementation of the proposed solution in real-time environments reveals that the proposed solution is more effective in reducing the soil salinity as compared to the traditional method.","source":"DOAJ","year":2022,"language":"","subjects":["Electrical engineering. Electronics. Nuclear engineering"],"doi":"10.1109/ACCESS.2022.3206009","url":"https://ieeexplore.ieee.org/document/9887960/","is_open_access":true,"published_at":"","score":66},{"id":"doaj_10.1049/cmu2.12356","title":"Spectrum sensing and resource allocation for 5G heterogeneous cloud radio access networks","authors":[{"name":"Hossein Safi"},{"name":"Ali Mohammad Montazeri"},{"name":"Javane Rostampoor"},{"name":"Saeedeh Parsaeefard"}],"abstract":"Abstract In this paper, the problem of opportunistic spectrum sharing for the next generation of wireless systems empowered by the cloud radio access network (C‐RAN) is studied. More precisely, low‐priority users employ cooperative spectrum sensing to detect a vacant portion of the spectrum that is not currently used by high‐priority users. The authors' aim is to maximize the overall throughput of the low‐priority users while guaranteeing the quality of service of the high‐priority users. This objective is attained by optimally adjusting spectrum sensing time, with respect to target probabilities of detection and false alarm, as well as dynamically allocating C‐RAN resources, that is, powers, sub‐carriers, remote radio heads, and base‐band units. To solve this problem, which is non‐convex and NP‐hard, a low‐complex iterative solution is proposed. Numerical results demonstrate the necessity of sensing time adjustment as well as effectiveness of the proposed solution.","source":"DOAJ","year":2022,"language":"","subjects":["Telecommunication"],"doi":"10.1049/cmu2.12356","url":"https://doi.org/10.1049/cmu2.12356","is_open_access":true,"published_at":"","score":66},{"id":"arxiv_2104.03948","title":"On Telecommunication Service Imbalance and Infrastructure Resource Deployment","authors":[{"name":"Chuanting Zhang"},{"name":"Shuping Dang"},{"name":"Basem Shihada"},{"name":"Mohamed-Slim Alouini"}],"abstract":"The digital divide restricting the access of people living in developing areas to the benefits of modern information and communications technologies has become a major challenge and research focus. To well understand and finally bridge the digital divide, we first need to discover a proper measure to characterize and quantify the telecommunication service imbalance. In this regard, we propose a fine-grained and easy-to-compute imbalance index, aiming to quantitatively link the relation among telecommunication service imbalance, telecommunication infrastructure, and demographic distribution. The mathematically elegant and generic form of the imbalance index allows consistent analyses for heterogeneous scenarios and can be easily tailored to incorporate different telecommunication policies and application scenarios. Based on this index, we also propose an infrastructure resource deployment strategy by minimizing the average imbalance index of any geographical segment. Experimental results verify the effectiveness of the proposed imbalance index by showing a high degree of correlation to existing congeneric but coarse-grained measures and the superiority of the infrastructure resource deployment strategy.","source":"arXiv","year":2021,"language":"en","subjects":["cs.CY","cs.IT"],"url":"https://arxiv.org/abs/2104.03948","pdf_url":"https://arxiv.org/pdf/2104.03948","is_open_access":true,"published_at":"2021-04-08T17:45:32Z","score":65},{"id":"arxiv_2108.11820","title":"Large Large deviations for spatial telecommunication systems: The boolean model","authors":[{"name":"A. K. Boahen"},{"name":"T. Katsekpor"},{"name":"K. Doku-Amponsah"}],"abstract":"Spatial telecommunication systems have evolved along the years, leading to some concerns that telecommunication companies are facing today. The main inquietude is the ability to provide quality service to customers or users in a dense regime. Therefore, questions such as : what is the best possible configurations of base stations and users that maximizes quality service? Is it possible to estimate and control the probability of bad service, which may be seen as a rare event? and many more arise. These questions often involve estimating the tail distribution of events, which falls under the scope of large deviation principles. In this article, we associate with the Boolean model, the empirical marked measure which will serve as a statistic for the intensity measure of the Marked Poisson Point Process of devices or users and the empirical connectivity measure which will serve as a statistic for coverage probability density of the spatial telecommunication area. For these empirical measures, prove large deviation principle (LDP) for well-defined empirical measures.","source":"arXiv","year":2021,"language":"en","subjects":["math.PR","cs.SI"],"url":"https://arxiv.org/abs/2108.11820","pdf_url":"https://arxiv.org/pdf/2108.11820","is_open_access":true,"published_at":"2021-08-26T14:37:23Z","score":65},{"id":"arxiv_2005.05165","title":"Large Deviation Principle for Empirical SINR Measure of Critical Telecommunication Networks","authors":[{"name":"Enoch Sakyi-Yeboah"},{"name":"Charles Kwofie"},{"name":"Kwabena Doku-Amponsah"}],"abstract":"For a \\emph{ powered Poisson process}, we define \\emph{Signal-to-Interference-plus-Noise Ratio}(SINR) and thesinr network as a Telecommunication Network. We define the Empirical Measures (\\emph{empirical powered measure}, \\emph{empirical link measure} and \\emph{empirical sinr measure}) of a class of Telecommunication Networks. For this class of Telecommunication Network we prove a joint large deviation principle for the empirical measures of the Telecommunication Networks. All our rate functions are expressed in terms of relative entropies.","source":"arXiv","year":2020,"language":"en","subjects":["cs.IT"],"url":"https://arxiv.org/abs/2005.05165","pdf_url":"https://arxiv.org/pdf/2005.05165","is_open_access":true,"published_at":"2020-05-11T14:58:33Z","score":64},{"id":"arxiv_2012.08157","title":"Certifying position-momentum entanglement at telecommunication wavelengths","authors":[{"name":"Lukas Achatz"},{"name":"Evelyn Ortega"},{"name":"Krishna Dovzhik"},{"name":"Rodrigo F. Shiozaki"},{"name":"Jorge Fuenzalida"},{"name":"Sören Wengerowsky"},{"name":"Martin Bohmann"},{"name":"Rupert Ursin"}],"abstract":"TheThe successful employment of high-dimensional quantum correlations and its integration in telecommunication infrastructures is vital in cutting-edge quantum technologies for increasing robustness and key generation rate. Position-momentum Einstein-Podolsky-Rosen (EPR) entanglement of photon pairs are a promising resource of such high-dimensional quantum correlations. Here, we experimentally certify EPR correlations of photon pairs generated by spontaneous parametric down-conversion (SPDC) in a nonlinear crystal with type-0 phase-matching at telecommunication wavelength for the first time. To experimentally observe EPR entanglement, we perform scanning measurements in the near- and far-field planes of the signal and idler modes. We certify EPR correlations with high statistical significance of up to 45 standard deviations. Furthermore, we determine the entanglement of formation of our source to be greater than one, indicating a dimensionality of greater than 2. Operating at telecommunication wavelengths around 1550 nm, our source is compatible with today's deployed telecommunication infrastructure, thus paving the way for integrating sources of high-dimensional entanglement into quantum-communication infrastructures.","source":"arXiv","year":2020,"language":"en","subjects":["quant-ph","physics.optics"],"doi":"10.1088/1402-4896/ac44b5","url":"https://arxiv.org/abs/2012.08157","pdf_url":"https://arxiv.org/pdf/2012.08157","is_open_access":true,"published_at":"2020-12-15T08:57:53Z","score":64},{"id":"doaj_10.5937/telfor2001034A","title":"A New Technique for Understanding Large-Scale Software Systems","authors":[{"name":"T. Al-Rousan"},{"name":"H. Abualese"}],"abstract":"Comprehending a huge execution trace is not a straightforward task due to the size of data to be processed. Detecting and removing utilities are useful to facilitate the understanding of software and decrease the complexity and size of the execution trace. The goal of this study is to develop a novel technique to minimize the complexity and the size of traces by detecting and removing utilities from the execution trace of object-oriented software. Two novel utility detection class metrics were suggested to decide the degree that a specific class can be counted as a utility class. Dynamic coupling analysis forms the basis for the proposed technique to address object-oriented features. The technique presented in this study has been tested by two case studies to evaluate the effectiveness of the proposed technique. The results from the case studies show the usefulness and effectiveness of our technique.","source":"DOAJ","year":2020,"language":"","subjects":["Telecommunication"],"doi":"10.5937/telfor2001034A","url":"\nhttp://journal.telfor.rs/Published/Vol12No1/Vol12No1_A7.pdf\n","pdf_url":"\nhttp://journal.telfor.rs/Published/Vol12No1/Vol12No1_A7.pdf\n","is_open_access":true,"published_at":"","score":64},{"id":"doaj_10.1186/s13634-020-00692-5","title":"Using the complement of the cosine to compute trigonometric functions","authors":[{"name":"David Guerrero Martos"},{"name":"Alejandro Millán Calderón"},{"name":"Jorge Juan Chico"},{"name":"Julian Viejo Cortés"},{"name":"Manuel J. Bellido Díaz"},{"name":"Paulino Ruiz-de-Clavijo Vazquez"},{"name":"Enrique Ostúa Arangüena"}],"abstract":"Abstract The computation of the sine and cosine functions is required in devices ranging from application-specific signal processors to general purpose floating-point units. Even in the latter case, the required functionality can be reduced to computing the sine and/or cosine of multiples of a constant angle. The latency of a sine/cosine generator can be reduced by using look-up tables. However, a direct implementation with look-up tables may be unfeasible if the input space is huge. In such a case, look-up tables with a number of entries lower than the size of the input space can be used indirectly. In previously published methods, the reduction in the number of table entries is obtained at the expense of increasing the table width and the computational cost. This paper introduces an alternative technique that makes it possible to reduce the size of the look-up tables as well as the required multiplications. The proposed technique can be used to implement sine/cosine generators of huge input space. It has been used to implement several twiddle factor generators in reconfigurable hardware and has enabled the number of look-up tables to be reduced by between 6 and 26% with respect to previous table-based techniques. Also, these implementations are about 50% faster than those based on Volder’s algorithm.","source":"DOAJ","year":2020,"language":"","subjects":["Telecommunication","Electronics"],"doi":"10.1186/s13634-020-00692-5","url":"http://link.springer.com/article/10.1186/s13634-020-00692-5","is_open_access":true,"published_at":"","score":64},{"id":"doaj_https://doi.org/10.24425/ijet.2019.130267","title":"Low Delay Sparse and Mixed Excitation CELP Coders for Wideband Speech Coding","authors":[{"name":"Przemysław Dymarski"}],"abstract":"Code Excited Linear Prediction (CELP) algorithms are proposed for compression of speech in 8 kHz band at switched or variable bit rate and algorithmic delay not exceeding 2 msec. Two structures of Low-Delay CELP coders are analyzed: Low-delay sparse excitation and mixed excitation CELP. Sparse excitation is based on MP-MLQ and multilayer models. Mixed excitation CELP algorithm stems from the narrowband G.728 standard. As opposed to G.728 LD-CELP coder, mixed excitation codebook consists of pseudorandom vectors and sequences obtained with Long-Term Prediction (LTP). Variable rate coding consists in maximizing vector dimension while keeping the required speech quality. Good speech quality (MOS=3.9 according to PESQ algorithm) is obtained at average bit rate 33.5 kbit/sec.","source":"DOAJ","year":2020,"language":"","subjects":["Electrical engineering. Electronics. Nuclear engineering","Telecommunication"],"doi":"https://doi.org/10.24425/ijet.2019.130267","url":"https://journals.pan.pl/Content/113746/PDF/10_2020.pdf","pdf_url":"https://journals.pan.pl/Content/113746/PDF/10_2020.pdf","is_open_access":true,"published_at":"","score":64},{"id":"arxiv_1910.11825","title":"Innovative Telecommunications Training through Flexible Radio Platforms","authors":[{"name":"Ali Fatih Demir"},{"name":"Berker Peköz"},{"name":"Selçuk Köse"},{"name":"Hüseyin Arslan"}],"abstract":"The ever-changing telecommunication industry is in severe need of a highly-skilled workforce to shape and deploy future generation communication systems. This article presents an innovative telecommunication training that is designed to satisfy this need. The training focuses on hardware layers of the open systems interconnection model. It integrates theory, numerical modeling, and hardware implementation to ensure a complete and long-lasting understanding. The key telecommunication concepts that are covered in the fundamental training phase are detailed along with best teaching practices. In addition, the methods that enrich the learning experience, such as gamified micro-tasks and interactive use of daily telecommunication devices, are featured. The project development case studies that cultivate creative thinking and scientific interest are highlighted. Also, a well-established guideline to compose the teaching environment that emphasizes hands-on experience is provided. Therefore, the presented training can be exemplary to other institutions that share the same mission to educate the distinguished engineers of the future.","source":"arXiv","year":2019,"language":"en","subjects":["eess.SP"],"doi":"10.1109/MCOM.001.1900245","url":"https://arxiv.org/abs/1910.11825","pdf_url":"https://arxiv.org/pdf/1910.11825","is_open_access":true,"published_at":"2019-10-25T16:09:58Z","score":63},{"id":"doaj_10.20535/RADAP.2019.77.30-35","title":"Мікросмужкові тривимірні ємнісні шлейфи","authors":[{"name":"S. H. Pervak"},{"name":"Ya. L. Zinher"},{"name":"Yu. F. Adamenko"},{"name":"V. O. Adamenko"},{"name":"E. A. Nelin"}],"abstract":"Мікросмужкові фільтри широко застосовують в радіоелектронних системах. Фільтри нижніх частот конструюють на основі квазізосереджених індуктивностей та ємностей. Квазізосереджену ємність виконують як мікросмужкову секцію із широким сигнальним провідником або як розімкнутий шлейф, з’єднаний з основною лінією. Традиційні конструкції таких ємностей двовимірні (2D) у вигляді відрізків мікросмужкової лінії. Запропоновані авторами тривимірні (3D) квазізосереджені елементи мають в 1,5…4 рази більші значення реактивних параметрів. Розімкнутий 3D-шлейф являє собою глухий металізований отвір у діелектричній основі, з’єднаний з основною лінією. У статті розглянуто конструктивні відмінності 2D та 3D ємнісних шлейфів. 3D-шлейф як порівняти з 2D-шлейфом має суттєво кращі параметри: його хвильовий імпеданс менший в 1,4…3,5 рази, а ємність більша в 1,6…4,1 рази. Оскільки для фільтра необхідні задані значення ємності, площа 3D-шлейфа відповідно менша. 3D-моделюванням проаналізовано особливості залежностей електричних параметрів 3D-шлейфа від його конструктивних параметрів. Показано, що частота режекції шлейфа дорівнює частоті резонанса шлейфа з паразитною індуктивністю, зумовленою шлейфним Т-з’єднанням. У разі традиційних розмірів контакта шлейфа та основної лінії ця індуктивність від’ємна, що призводить до збільшення значення частоти режекції і, відповідно, погіршення крутості амплітудно-частотних характеристик шлейфа та фільтра. Для зменшення паразитної індуктивності запропоновано конструктивне рішення у вигляді контактного майданчика між лінією та шлейфом. Досліджено залежності цієї індуктивності від конструктивних параметрів шлейфа та майданчика. Оптимізація розмірів контактного майданчика дозволяє оптимізувати значення індуктивності з умови необхідної крутості амплітудно-частотної характеристики. Запропоновано одновимірну модель 3D-шлейфа, що характеризує його еквівалентними хвильовим імпедансом та відносною діелектричною проникністю. Ця модель може використовуватися як модель першого наближення під час проектування та дослідження мікросмужкових фільтрів на основі ємнісних 3D-шлейфів.","source":"DOAJ","year":2019,"language":"","subjects":["Telecommunication"],"doi":"10.20535/RADAP.2019.77.30-35","url":"http://doi.radap.kpi.ua/article/view/185263","is_open_access":true,"published_at":"","score":63}],"total":108630,"page":1,"page_size":20,"sources":["arXiv","DOAJ","CrossRef"],"query":"Telecommunication"}