Telecom最新文献_第6页

Prediction of RF-EMF Exposure by Outdoor Drive Test Measurements 通过室外驱动测试测量预测RF-EMF暴露

Telecom Pub Date : 2022-06-28 DOI: 10.3390/telecom3030021

Shanshan Wang, T. Mazloum, J. Wiart

{"title":"Prediction of RF-EMF Exposure by Outdoor Drive Test Measurements","authors":"Shanshan Wang, T. Mazloum, J. Wiart","doi":"10.3390/telecom3030021","DOIUrl":"https://doi.org/10.3390/telecom3030021","url":null,"abstract":"In this paper, we exploit the artificial neural network (ANN) model for a spatial reconstruction of radio-frequency (RF) electromagnetic field (EMF) exposure in an outdoor urban environment. To this end, we have carried out a drive test measurement campaign covering a large part of Paris, along a route of approximately 65 Km. The electric (E) field strength has been recorded over a wide band ranging from 700 to 2700 MHz. From these measurement data, the E-field strength is extracted and computed for each frequency band of each telecommunication operator. First, the correlation between the E-fields at different frequency bands is computed and analyzed. The results show that a strong correlation of E-field levels is observed for bands belonging to the same operator. Then, we build ANN models with input data encompassing information related to distances to N neighboring base stations (BS), receiver location and time variation. We consider two different models. The first one is a fully connected ANN model, where we take into account the N nearest BSs ignoring the corresponding operator. The second one is a hybrid model, where we consider locally connected blocks with the N nearest BSs for each operator, followed by fully connected layers. The results show that the hybrid model achieves better performance than the fully connected one. Among N∈{3,5,7}, we found out that with N=3, the proposed hybrid model allows a good prediction of the exposure level while the maintaining acceptable complexity of the model.","PeriodicalId":301561,"journal":{"name":"Telecom","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131859073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Design Procedure of a Frequency Reconfigurable Metasurface Antenna at mmWave Band 毫米波波段频率可重构超表面天线的设计过程

Telecom Pub Date : 2022-06-09 DOI: 10.3390/telecom3020020

Bokamoso Kebatho Ledimo, Pako Moaro, Reuben Ramogomana, M. Mosalaosi, Bokamoso Basutli

{"title":"Design Procedure of a Frequency Reconfigurable Metasurface Antenna at mmWave Band","authors":"Bokamoso Kebatho Ledimo, Pako Moaro, Reuben Ramogomana, M. Mosalaosi, Bokamoso Basutli","doi":"10.3390/telecom3020020","DOIUrl":"https://doi.org/10.3390/telecom3020020","url":null,"abstract":"The use of the millimeter wave (mmWave) spectrum and further exploration of sub-mmWave has led to a new era in wireless communication, as the need for higher data rates grows. High frequencies, on the other hand, incur a higher path loss, requiring an increase in antenna gain requirements. Metasurfaces, which emerge as a promising technology for mitigating path loss effects by utilizing two dimensional (2D) arrays of engineered meta-atoms resembling metamaterials that control the surface’s electromagnetic response have been introduced. Currently, metasurfaces are primarily considered as passive reflecting devices in wireless communications, assisting conventional transceivers in shaping propagation environments. This paper presents an alternative application of metasurfaces for wireless communications as active reconfigurable antennas for next generation transceivers. A framework that demonstrates the design process of a metasurface antenna structure was introduced and further used to design a 4 × 4 array and its reconfigurable counterpart. In contrast to conventional phased array antennas, a reconfigurable metasurface (RMS) antenna does not require phase-shifters and amplifiers, which leads to reduced cost. Instead, each individual element achieves reconfigurability by shifting the resonating frequency using semiconductor devices such as PIN diodes. The proposed metasurface antenna is designed to operate at a frequency of 28 GHz and 40 GHz. In addition, an increase in gain and directivity was observed when diodes were added to the metasurface antenna array. However, due to PIN diodes being connected to metallic strips in the metasurface antenna array, loss can occur due to power dissipation, which results in a decrease in radiation efficiency.","PeriodicalId":301561,"journal":{"name":"Telecom","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-06-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125016917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

Stock Market Prediction Using Microblogging Sentiment Analysis and Machine Learning 基于微博情绪分析和机器学习的股市预测

Telecom Pub Date : 2022-05-27 DOI: 10.3390/telecom3020019

Paraskevas Koukaras, Christina Nousi, Christos Tjortjis

引用次数: 11

LoRaWAN Communication Protocols: A Comprehensive Survey under an Energy Efficiency Perspective LoRaWAN通信协议:能效视角下的综合研究

Telecom Pub Date : 2022-05-25 DOI: 10.3390/telecom3020018

Konstantina Banti, Ioanna Karampelia, Thomas Dimakis, Alexandros-Apostolos A. Boulogeorgos, Thomas S. Kyriakidis, M. Louta

{"title":"LoRaWAN Communication Protocols: A Comprehensive Survey under an Energy Efficiency Perspective","authors":"Konstantina Banti, Ioanna Karampelia, Thomas Dimakis, Alexandros-Apostolos A. Boulogeorgos, Thomas S. Kyriakidis, M. Louta","doi":"10.3390/telecom3020018","DOIUrl":"https://doi.org/10.3390/telecom3020018","url":null,"abstract":"Long range wide area networks (LoRaWANs) have recently received intense scientific, research, and industrial interest. LoRaWANs play a pivotal role in Internet of Things (IoT) applications due to their capability to offer large coverage without sacrificing the energy efficiency and, thus the battery life, of end-devices. Most published contributions assume that LoRaWAN gateways (GWs) are plugged into the energy grid; thus, neglecting the network lifetime constraint due to power storage limitations. However, there are several verticals, including precision agriculture, forest protection, and others, in which it is difficult or even impossible to connect the GW to the power grid or to perform battery replacement at the end-devices. Consequently, maximizing the networks’ energy efficiency is expected to have a crucial impact on maximizing the network lifetime. Motivated by this, as well as the observation that the overall LoRaWAN network energy efficiency is significantly affected by the selected communication protocol, in this paper, we identify and discuss critical aspects and research challenges involved in the design of a LoRaWAN communication protocol, under an energy efficiency perspective. Building upon our findings, research directions towards a novel GreenLoRaWAN communication protocol are given, focusing on achieving energy efficiency, robustness, and scalability.","PeriodicalId":301561,"journal":{"name":"Telecom","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121715185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 4

Monitoring Saffron Crops with UAVs 用无人机监控藏红花作物

Telecom Pub Date : 2022-05-13 DOI: 10.3390/telecom3020017

Konstantinos Kiropoulos, Dimosthenis C. Tsouros, Foteini Dimaraki, Anna Triantafyllou, S. Bibi, P. Sarigiannidis, P. Angelidis

引用次数: 2

A Brief Overview of Energy Efficiency Resources in Emerging Wireless Communication Systems 新兴无线通信系统的能源效率概述

Telecom Pub Date : 2022-04-28 DOI: 10.3390/telecom3020016

A. Ibhaze, A. Imoize, O. Okoyeigbo

{"title":"A Brief Overview of Energy Efficiency Resources in Emerging Wireless Communication Systems","authors":"A. Ibhaze, A. Imoize, O. Okoyeigbo","doi":"10.3390/telecom3020016","DOIUrl":"https://doi.org/10.3390/telecom3020016","url":null,"abstract":"It is crucial to design new communication technologies to surmount the setbacks in RF communication systems. A suitable energy-efficiency scheme helps evade needless energy consumption in wireless communication. Appropriate choice of the most suitable energy-efficiency scheme aids in selecting the most energy-efficient equipment to minimize the expense of energy towards decreasing individual network element energy consumption without affecting their unique features. This review presents the energy efficiency challenges in wireless communication by employing different technologies. The emergence of visible light communication (VLC) provides an energy-efficient wireless communication system despite the various challenges inherent in its adoption that limit its physical realization. This work seeks to harness the potential of the transmission capabilities of VLC while providing an insight into novel practical implementation techniques. The work also addresses the energy consumption problem of low-active components and idle period of active components of base stations by using sleep modes for their systematic turning off and on. The high cost of power supply and the environmental emission of gases from base stations are also addressed by integrating a renewable energy resource into the conventional standalone diesel generators. Overall, the work provides an overview of information necessary for foundational research in energy-efficient resources applied to emerging wireless communication systems.","PeriodicalId":301561,"journal":{"name":"Telecom","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128581229","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 7

Toward SDM-Based Submarine Optical Networks: A Review of Their Evolution and Upcoming Trends 基于sdm的海底光网络:发展与展望

Telecom Pub Date : 2022-04-11 DOI: 10.3390/telecom3020015

Charalampos Papapavlou, Konstantinos Paximadis, Dimitrios Uzunidis, Ioannis Tomkos

{"title":"Toward SDM-Based Submarine Optical Networks: A Review of Their Evolution and Upcoming Trends","authors":"Charalampos Papapavlou, Konstantinos Paximadis, Dimitrios Uzunidis, Ioannis Tomkos","doi":"10.3390/telecom3020015","DOIUrl":"https://doi.org/10.3390/telecom3020015","url":null,"abstract":"Submarine networks have evolved alongside terrestrial ones over the past several decades. Although there are similarities between these two network categories (e.g., the need to cover ultra-long-haul distances and transport huge amounts of data), there are also important differences that have dictated their different evolutionary paths. Space division multiplexing (SDM) promises to be the ultimate solution to cover future capacity needs and overcome problems of both networks. In this work, we review recent and future submarine technologies, focusing on all critical sectors: cable systems, amplifiers’ technology, submarine network architectures, electrical power- feeding issues, economics, and security. Such an analysis, with the level of detail provided in this manuscript, is not available in the literature so far. We first overview all recently announced SDM-based submarine cable systems, compare their performance (capacity-distance product), and analyze the reasons that led to the first SDM submarine deployment. Also, we report up-to-date experimental results of submarine transmission demonstrations and perform a qualitative categorization that relies on their features. Moreover, based on all latest advances and our study findings, we try to predict the future of SDM submarine optical networks mainly in the fields of fiber types, fiber counts per cable, fiber-coating variants, modulation formats, as well as the type and layout structure of optical amplifiers. More specifically, results show that SDM can offer higher capacities (in order of Pb/s) compared to its counterparts, supported by novel network technologies: pump-farming amplification schemes, high counts up to 50 parallel fiber pairs, thinner fiber coating variants (200 μm), and optimum spectral efficiency (2–3 b/s/Hz). Finally, we conclude that tradeoffs between capacity and implementation complexity and cost will have to be carefully considered for future deployments of submarine cable systems.","PeriodicalId":301561,"journal":{"name":"Telecom","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134171505","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

Experimental Evaluation of Hybrid Fibre–Wireless System for 5G Networks 5G网络混合光纤无线系统的实验评估

Telecom Pub Date : 2022-04-02 DOI: 10.3390/telecom3020014

M. Hadi, Jian Song, Sunish Kumar Orappanpara Soman, A. Rahimian, A. Cheema

{"title":"Experimental Evaluation of Hybrid Fibre–Wireless System for 5G Networks","authors":"M. Hadi, Jian Song, Sunish Kumar Orappanpara Soman, A. Rahimian, A. Cheema","doi":"10.3390/telecom3020014","DOIUrl":"https://doi.org/10.3390/telecom3020014","url":null,"abstract":"This article describes a novel experimental study considering a multiband fibre–wireless system for constructing the transport network for fifth-generation (5G) networks. This study describes the development and testing of a 5G new radio (NR) multi-input multi-output (MIMO) hybrid fibre–wireless (FiWi) system for enhanced mobile broadband (eMBB) using digital pre-distortion (DPD). Analog radio over fibre (A-RoF) technology was used to create the optical fronthaul (OFH) that includes a 3 GHz supercell in a long-range scenario as well as a femtocell scenario using the 20 GHz band. As a proof of concept, a Mach Zehnder modulator with two independent radio frequency waveforms modifies a 1310 nm optical carrier using a distributed feedback laser across 10 km of conventional standard single-mode fibre. It may be inferred that a hybrid FiWi-based MIMO-enabled 5G NR system based on OFH could be a strong competitor for future mobile haul applications. Moreover, a convolutional neural network (CNN)-based DPD is used to improve the performance of the link. The error vector magnitude (EVM) performance for 5G NR bands is predicted to fulfil the Third Generation Partnership Project’s (3GPP) Release 17 standards.","PeriodicalId":301561,"journal":{"name":"Telecom","volume":"17 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125179245","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Analysis and Estimation of Economic Influence of IoT and Telecommunication in Regional Media Based on Evolution and Electronic Markets in Romania 基于罗马尼亚演进和电子市场的物联网和电信在区域媒体中的经济影响分析与估计

Telecom Pub Date : 2022-03-04 DOI: 10.3390/telecom3010013

Andreea Nistor, Eduard Zadobrischi

{"title":"Analysis and Estimation of Economic Influence of IoT and Telecommunication in Regional Media Based on Evolution and Electronic Markets in Romania","authors":"Andreea Nistor, Eduard Zadobrischi","doi":"10.3390/telecom3010013","DOIUrl":"https://doi.org/10.3390/telecom3010013","url":null,"abstract":"The interconnection of devices, intended to collect and transmit data via the Internet, is called the Internet of Things (IoT). This technology has the potential to revolutionize both the economic and industrial sectors, especially in terms of data confidentiality and information security. New media, with a merger between those two, have increasingly replaced traditional media, but many researchers characterize them as two distinct but interconnected types of media. From the traditional media, with its technological evolution, the IoT has supported the development of the media through the emergence of applications, websites, and social networks designed to spread information worldwide. This research focuses on how the IoT has the ability to influence economic growth by trying to determine the impact of the IoT through theories and the evolution of economic growth. Thus, the concept of the IoT is interdependent on information and communications technology and, from an economic point of view, is correlated with productivity. In addition, the processes that have an impact on the media are those of an economic nature, all of which are interconnected with progress, innovation, and the promotion of goods and services. At the same time, this paper aims to determine the correlation between IoT and the economy, with a focus on the media, which has the main result of the development of new businesses. Thus, a bibliometric analysis of the scientific papers on the Web of Science platform regarding the IoT field was performed, in order to identify the current state of knowledge in this field. The results of this analysis highlighted that both the IoT and the economy are shaped by innovation, opportunities, and development.","PeriodicalId":301561,"journal":{"name":"Telecom","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114200317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

3GPP 5G V2X Scenarios: Performance of QoS Parameters Using Turbo Codes 3GPP 5G V2X场景:基于Turbo码的QoS参数性能

Telecom Pub Date : 2022-03-01 DOI: 10.3390/telecom3010012

Dimitrios Kosmanos, C. Chaikalis, I. Savvas

{"title":"3GPP 5G V2X Scenarios: Performance of QoS Parameters Using Turbo Codes","authors":"Dimitrios Kosmanos, C. Chaikalis, I. Savvas","doi":"10.3390/telecom3010012","DOIUrl":"https://doi.org/10.3390/telecom3010012","url":null,"abstract":"Cellular vehicle-to-everything (C-V2X) communication has recently gained attention in industry and academia. Different implementation scenarios have been derived by the 3rd Generation Partnership Project (3GPP) 5th Generation (5G) Vehicle-to-Everything (V2X) standard, Release 16. Quality of service (QoS) is important to achieve reliable communication and parameters which have to be considered are reliability, end-to-end latency, data rate, communication range, throughput and vehicle density for an urban area. However, it would be desirable to design a dynamic selecting system (with emphasis on channel coding parameters selection) so that all QoS parameters are satisfied. Having this idea in mind, in this work we examine nine V2X implementation scenarios using Long Term Evolution (LTE) turbo coding with a geometry−based efficient propagation model for vehicle-to-vehicle communication (GEMV), where we consider the above QoS parameters for SOVA, log-MAP and max-log-MAP decoding algorithms. Our study is suitable for 3GPP cooperative sensing, for the eight scenarios considering medium and large signal-noise-ratio (SNR) values. The proposed model is sustainable despite a doubled data rate, which results in a minimal bit error rate (BER) performance loss up to 1.85 dB. In this case tripling the data rate results in a further 1 dB loss. Moreover, a small loss up to 0.4 dB is seen for a vehicle speed increase from 60 km/h to 100 km/h. Finally, increasing vehicle density has no effect on the implemented 3GPP scenario considering end-to-end latency, irrespectively from the decoding algorithm.","PeriodicalId":301561,"journal":{"name":"Telecom","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2022-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121708716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3