Download or read book From 5g To 6g And Beyond The 7 Cs Of Future Communications written by Kiat Seng Yeo and published by World Scientific. This book was released on 2023-04-14 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt: With speeds of up to 20 gigabits per second and the ability to support up to one million devices per square kilometer, 5G — the current generation of mobile communications technology — may seem impressive, but 6G is set to take these capabilities even further. Envisioned to deliver a peak data rate of 1 terabit per second and latency of 100 microseconds or less, 6G must be able to seamlessly and securely deliver data in an ever increasingly saturated network of wireless connections without exceeding the energy requirements of 5G.This book covers every aspect of future communications, from key technologies, to design challenges, network requirements, and users experiences; to standardization, chip design, and industry applications from 5G to 6G. It presents the requirements and use cases of 6G, RF transceivers roadmap for 2030 and beyond, and modeling of RF devices for 5G/6G applications. In here, a modified Shannon's capacity formula that is critical for future advanced wireless communications such as 6G is discussed for the first time. It also presents the standardization of 6G wireless communication systems with emphasis on Standard Development Organizations (SDOs), regulatory bodies and administrations, ITU, industry forums, and 6G standard timeline. The book presents an RF/mm-wave integrated circuit design for future communications to provides readers with an easy-to-understand overview of voltage-controlled oscillators, power amplifiers, low-noise amplifiers, frequency synthesizers, high-frequency dividers, and chip-to-chip communications isolation technology.This book is an excellent reference for readers specializing in electrical and electronic engineering, wireless communication, integrated circuit design, circuits and systems, to learn more about 5G and even 6G communication standards and RF/mm-wave IC design. In particular, professionals working in the foundry, fabless semiconductor companies, original equipment manufacturers, and integrated device manufacturers will also benefit from this book.

Download or read book From 5G to 6G and Beyond written by Kiat Seng Yeo and published by . This book was released on 2023 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: "With speeds of up to 20-gigabits per second and the ability to support up to one million devices per square kilometer, 5G - the current generation of mobile communications technology - may seem impressive, but 6G is set to take these capabilities even further. Envisioned to deliver a peak data rate of 1 Terabit per second and latency of 100 microseconds or less, 6G must be able to seamlessly and securely deliver data in an ever increasingly saturated network of wireless connections without exceeding the energy requirements of 5G. This book covers every aspect of future communication from key technologies, to design challenges, network requirements and users' experiences to standardization, chip design, and industry applications from 5G to 6G. It presents the requirements and use cases of 6G, RF transceivers roadmap for 2030 and beyond, and modelling of RF devices for 5G/6G applications. In here, a modified Shannon's capacity formula that is critical for future advanced wireless communication such as 6G is discussed for the first time. It also presents the standardization of 6G wireless communication systems with emphasis on Standard Development Organizations (SDOs), regulatory bodies and administrations, ITU, industry forums, and 6G standard timeline. The book presents RF/mm-wave integrated circuit design for future communications to provides readers with an easy-to-understand overview of voltage-controlled oscillators, power amplifiers, low-noise amplifiers, frequency synthesizers, high-frequency dividers, and chip-to-chip communications isolation technology. This book is an excellent reference for readers specializing in electrical & electronic engineering, wireless communication, integrated circuit design, circuits and systems, to learn more about the 5G and even 6G communication standards, and RF/mm-wave IC design. In particularly, professionals working in the foundry, fabless semiconductor company, original equipment manufacturer and integrated device manufacturer will also benefit from this book"--

Download or read book Future Hype written by Robert B. Seidensticker and published by ReadHowYouWant.com. This book was released on 2006 with total page 382 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Tactile Internet written by Frank H. P. Fitzek and published by Academic Press. This book was released on 2021-03-06 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt: Tactile Internet with Human-in-the-Loop describes the change from the current Internet, which focuses on the democratization of information independent of location or time, to the Tactile Internet, which democratizes skills to promote equity that is independent of age, gender, sociocultural background or physical limitations. The book promotes the concept of the Tactile Internet for remote closed-loop human-machine interaction and describes the main challenges and key technologies. Current standardization activities in the field for IEEE and IETF are also described, making this book an ideal resource for researchers, graduate students, and industry R&D engineers in communications engineering, electronic engineering, and computer engineering. - Provides a comprehensive reference that addresses all aspects of the Tactile Internet – technologies, engineering challenges, use cases and standards - Written by leading researchers in the field - Presents current standardizations surrounding the IETF and the IEEE - Contains use cases that illustrate practical applications

Download or read book Massive MIMO Systems written by Kazuki Maruta and published by MDPI. This book was released on 2020-07-03 with total page 330 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multiple-input, multiple-output (MIMO), which transmits multiple data streams via multiple antenna elements, is one of the most attractive technologies in the wireless communication field. Its extension, called ‘massive MIMO’ or ‘large-scale MIMO’, in which base station has over one hundred of the antenna elements, is now seen as a promising candidate to realize 5G and beyond, as well as 6G mobile communications. It has been the first decade since its fundamental concept emerged. This Special Issue consists of 19 papers and each of them focuses on a popular topic related to massive MIMO systems, e.g. analog/digital hybrid signal processing, antenna fabrication, and machine learning incorporation. These achievements could boost its realization and deepen the academic and industrial knowledge of this field.

Download or read book THz Communications written by Thomas Kürner and published by Springer Nature. This book was released on 2021-12-07 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book describes the fundamentals of THz communications, spanning the whole range of applications, propagation and channel models, RF transceiver technology, antennas, baseband techniques, and networking interfaces. The requested data rate in wireless communications will soon reach from 100 Gbit/s up to 1 Tbps necessitating systems with ultra-high bandwidths of several 10s of GHz which are available only above 200 GHz. In the last decade, research at these frequency bands has made significant progress, enabling mature experimental demonstrations of so-called THz communications, which are thus expected to play a vital role in future wireless networks. In addition to chapters by leading experts on the theory, modeling, and implementation of THz communication technology, the book also features the latest experimental results and addresses standardization and regulatory aspects. This book will be of interest to both academic researchers and engineers in the telecommunications industry.

Download or read book Multiple Access Techniques for 5G Wireless Networks and Beyond written by Mojtaba Vaezi and published by Springer. This book was released on 2018-08-23 with total page 692 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents comprehensive coverage of current and emerging multiple access, random access, and waveform design techniques for 5G wireless networks and beyond. A definitive reference for researchers in these fields, the book describes recent research from academia, industry, and standardization bodies. The book is an all-encompassing treatment of these areas addressing orthogonal multiple access and waveform design, non-orthogonal multiple access (NOMA) via power, code, and other domains, and orthogonal, non-orthogonal, and grant-free random access. The book builds its foundations on state of the art research papers, measurements, and experimental results from a variety of sources.

Download or read book Integrated Sensing and Communications for Future Wireless Networks written by Aryan Kaushik and published by Elsevier. This book was released on 2024-12-02 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt: Integrated Sensing and Communications for Future Wireless Networks: Principles, Advances and Key Enabling Technologies presents the principles, methods, and algorithms of ISAC, an overview of the essential enabling technologies, as well as the latest research and future directions. Suitable for academic researchers and post graduate students as well as industry R&D engineers, this book is the definitive reference in this interdisciplinary field that is being seen as a technology to enable emerging applications such as vehicular networks, environmental monitoring, remote sensing, IoT, smart cities. Importantly, ISAC has been identified as an enabling technology for B5G/6G, and the next-generation Wi-Fi system. ISAC brings together a range of technologies: radar sensing, reconfigurable intelligent surfaces, holographic surfaces through to high frequency terahertz, PHY security, channel signaling, multiple access, and machine learning. - Gives an overview of ISAC technology – its potential, the challenges and future research trajectory - Presents the future directions of ISAC - Includes discussion of the following technologies: i. Intelligent Metasurfaces for ISAC; ii. Machine Learning and AI for ISAC; iii. ISAC Waveform Design and Full-Duplex; iv. Millimeter Wave, Terahertz, and Beamforming for ISAC; v. Network Architectural Aspects of Integrating Sensing

Download or read book Handbook of Position Location written by Reza Zekavat and published by John Wiley & Sons. This book was released on 2019-03-06 with total page 1376 pages. Available in PDF, EPUB and Kindle. Book excerpt: A comprehensive review of position location technology — from fundamental theory to advanced practical applications Positioning systems and location technologies have become significant components of modern life, used in a multitude of areas such as law enforcement and security, road safety and navigation, personnel and object tracking, and many more. Position location systems have greatly reduced societal vulnerabilities and enhanced the quality of life for billions of people around the globe — yet limited resources are available to researchers and students in this important field. The Handbook of Position Location: Theory, Practice, and Advances fills this gap, providing a comprehensive overview of both fundamental and cutting-edge techniques and introducing practical methods of advanced localization and positioning. Now in its second edition, this handbook offers broad and in-depth coverage of essential topics including Time of Arrival (TOA) and Direction of Arrival (DOA) based positioning, Received Signal Strength (RSS) based positioning, network localization, and others. Topics such as GPS, autonomous vehicle applications, and visible light localization are examined, while major revisions to chapters such as body area network positioning and digital signal processing for GNSS receivers reflect current and emerging advances in the field. This new edition: Presents new and revised chapters on topics including localization error evaluation, Kalman filtering, positioning in inhomogeneous media, and Global Positioning (GPS) in harsh environments Offers MATLAB examples to demonstrate fundamental algorithms for positioning and provides online access to all MATLAB code Allows practicing engineers and graduate students to keep pace with contemporary research and new technologies Contains numerous application-based examples including the application of localization to drone navigation, capsule endoscopy localization, and satellite navigation and localization Reviews unique applications of position location systems, including GNSS and RFID-based localization systems The Handbook of Position Location: Theory, Practice, and Advances is valuable resource for practicing engineers and researchers seeking to keep pace with current developments in the field, graduate students in need of clear and accurate course material, and university instructors teaching the fundamentals of wireless localization.

Download or read book 5G Outlook Innovations and Applications written by Ramjee Prasad and published by River Publishers. This book was released on 2016-07-01 with total page 260 pages. Available in PDF, EPUB and Kindle. Book excerpt: 5G Outlook - Innovations and Applications is a collection of the recent research and development in the area of the Fifth Generation Mobile Technology (5G), the future of wireless communications. Plenty of novel ideas and knowledge of the 5G are presented in this book as well as divers applications from health science to business modeling. The authors of different chapters contributed from various countries and organizations. The chapters have also been presented at the 5th IEEE 5G Summit held in Aalborg on July 1, 2016. The book starts with a comprehensive introduction on 5G and its need and requirement. Then millimeter waves as a promising spectrum to 5G technology is discussed. The book continues with the novel and inspiring ideas for the future wireless communication usage and network. Further, some technical issues in signal processing and network design for 5G are presented. Finally, the book ends up with different applications of 5G in distinct areas. Topics widely covered in this book are: 5G technology from past to present to the futureMillimeter- waves and their characteristicsSignal processing and network design issues for 5GApplications, business modeling and several novel ideas for the future of 5G

Download or read book Security and Privacy written by Pantelimon Stănică and published by Springer Nature. This book was released on 2021-04-02 with total page 183 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book consists of refereed selected papers from the International Conference on Security & Privacy – ICSP 2020. The book is focused on the state-of-the-art developments of network security, secure cryptographic protocols, post-quantum cryptography, quantum cryptography, block-chain and cryptocurrency, IoT security and privacy, cloud security, machine learning in cybersecurity, and other disciplines related to security and privacy. In this book, a wide variety of basic security primitives are discussed along with recent developments in some advanced topics like functional encryption, two-party/multi-party computation, bitcoin, cryptocurrency, and post-quantum security.

Download or read book 5G Networks written by Anwer Al-Dulaimi and published by John Wiley & Sons. This book was released on 2018-10-02 with total page 786 pages. Available in PDF, EPUB and Kindle. Book excerpt: A reliable and focused treatment of the emergent technology of fifth generation (5G) networks This book provides an understanding of the most recent developments in 5G, from both theoretical and industrial perspectives. It identifies and discusses technical challenges and recent results related to improving capacity and spectral efficiency on the radio interface side, and operations management on the core network side. It covers both existing network technologies and those currently in development in three major areas of 5G: spectrum extension, spatial spectrum utilization, and core network and network topology management. It explores new spectrum opportunities; the capability of radio access technology; and the operation of network infrastructure and heterogeneous QoE provisioning. 5G Networks: Fundamental Requirements, Enabling Technologies, and Operations Management is split into five sections: Physical Layer for 5G Radio Interface Technologies; Radio Access Technology for 5G Networks; 5G Network Interworking and Core Network Advancements; Vertical 5G Applications; and R&D and 5G Standardization. It starts by introducing emerging technologies in 5G software, hardware, and management aspects before moving on to cover waveform design for 5G and beyond; code design for multi-user MIMO; network slicing for 5G networks; machine type communication in the 5G era; provisioning unlicensed LAA interface for smart grid applications; moving toward all-IT 5G end-to-end infrastructure; and more. This valuable resource: Provides a comprehensive reference for all layers of 5G networks Focuses on fundamental issues in an easy language that is understandable by a wide audience Includes both beginner and advanced examples at the end of each section Features sections on major open research challenges 5G Networks: Fundamental Requirements, Enabling Technologies, and Operations Management is an excellent book for graduate students, academic researchers, and industry professionals, involved in 5G technology.

Download or read book Security and Privacy Vision in 6G written by Pawani Porambage and published by John Wiley & Sons. This book was released on 2023-08-08 with total page 389 pages. Available in PDF, EPUB and Kindle. Book excerpt: SECURITY AND PRIVACY VISION IN 6G Prepare for the future of mobile communication with this comprehensive study 6G is the next frontier in mobile communication, with development of 6G standards slated to begin as early as 2026. As telecommunications networks become faster and more intelligent, security and privacy concerns are critical. In an increasingly connected world, there is an urgent need for user data to be safeguarded and system security enhanced against a new generation of threats. Security and Privacy Vision in 6G provides a comprehensive survey of these threats and the emerging techniques for safeguarding against them. It includes mechanisms for prediction, detection, mitigation, and prevention, such that threats to privacy and security can be forestalled at any stage. Fully engaged with proposed 6G architectures, it is an essential resource for mobile communications professionals looking for a head start on the technology of the future. Security and Privacy Vision in 6G readers will also find: Detailed coverage of topics including edge intelligence and cloudification, industrial automation, collaborative robots, and more Treatment balancing the practical and the theoretical An editorial team with decades of international network technology experience in both industry and academia Security and Privacy Vision in 6G is a vital reference for network security professionals and for postgraduate and advanced undergraduate students in mobile communications and network security-related fields.

Download or read book Micro Electronics and Telecommunication Engineering written by Devendra Kumar Sharma and published by Springer Nature. This book was released on 2022-02-28 with total page 813 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book presents high-quality papers from the Fourth International Conference on Microelectronics and Telecommunication Engineering (ICMETE 2021). It discusses the latest technological trends and advances in major research areas such as microelectronics, wireless communications, optical communication, signal processing, image processing, big data, cloud computing, artificial intelligence and sensor network applications. This book includes the contributions of national and international scientists, researchers, and engineers from both academia and the industry. The contents of this volume will be useful to researchers, professionals, and students alike.

Download or read book Cell Free Massive MIMO written by Giovanni Interdonato and published by Linköping University Electronic Press. This book was released on 2020-09-09 with total page 75 pages. Available in PDF, EPUB and Kindle. Book excerpt: The fifth generation of mobile communication systems (5G) is nowadays a reality. 5G networks are been deployed all over the world, and the first 5G-capable devices (e.g., smartphones, tablets, wearable, etc.) are already commercially available. 5G systems provide unprecedented levels of connectivity and quality of service (QoS) to cope with the incessant growth in the number of connected devices and the huge increase in data-rate demand. Massive MIMO (multiple-input multiple-output) technology plays a key role in 5G systems. The underlying principle of this technology is the use of a large number of co-located antennas at the base station, which coherently transmit/receive signals to/from multiple users. This signal co-processing at multiple antennas leads to manifold benefits: array gain, spatial diversity and spatial user multiplexing. These elements enable to meet the QoS requirements established for the 5G systems. The major bottleneck of massive MIMO systems as well as of any cellular network is the inter-cell interference, which affects significantly the cell-edge users, whose performance is already degraded by the path attenuation. To overcome these limitations and provide uniformly excellent service to all the users we need a more radical approach: we need to challenge the cellular paradigm. In this regard, cell-free massive MIMO constitutes the paradigm shift. In the cell-free paradigm, it is not the base station surrounded by the users, but rather it is each user being surrounded by smaller, simpler, serving base stations referred to as access points (APs). In such a system, each user experiences being in the cell-center, and it does not experience any cell boundaries. Hence, the terminology cell-free. As a result, users are not affected by inter-cell interference, and the path attenuation is significantly reduced due to the presence of many APs in their proximity. This leads to impressive performance. Although appealing from the performance viewpoint, the designing and implementation of such a distributed massive MIMO system is a challenging task, and it is the object of this thesis. More specifically, in this thesis we study: Paper A) The large potential of this promising technology in realistic indoor/outdoor scenarios while also addressing practical deployment issues, such as clock synchronization among APs, and cost-efficient implementations. We provide an extensive description of a cell-free massive MIMO system, emphasizing strengths and weaknesses, and pointing out differences and similarities with existing distributed multiple antenna systems, such as Coordinated MultiPoint (CoMP). Paper B) How to preserve the scalability of the system, by proposing a solution related to data processing, network topology and power control. We consider a realistic scenario where multiple central processing units serve disjoint subsets of APs, and compare the spectral efficiency provided by the proposed scalable framework with the canonical cell-free massive MIMO and CoMP. Paper C) How to improve the spectral efficiency (SE) in the downlink (DL), by devising two distributed precoding schemes, referred to as local partial zero-forcing (ZF) and local protective partial ZF, that provide an adaptable trade-off between interference cancelation and boosting of the desired signal, with no additional front-haul overhead, and that are implementable by APs with very few antennas. We derive closed-form expressions for the achievable SE under the assumption of independent Rayleigh fading channel, channel estimation error and pilot contamination. These closed-form expressions are then used to devise optimal max-min fairness power control. Paper D) How to further improve the SE by letting the user estimate the DL channel from DL pilots, instead of relying solely on the knowledge of the channel statistics. We derive an approximate closed-form expression of the DL SE for conjugate beamforming (CB), and assuming independent Rayleigh fading. This expression accounts for beamformed DL pilots, estimation errors and pilot contamination at both the AP and the user side. We devise a sequential convex approximation algorithm to globally solve the max-min fairness power control optimization problem, and a greedy algorithm for uplink (UL) and DL pilot assignment. The latter consists in jointly selecting the UL and DL pilot pair, for each user, that maximizes the smallest SE in the network. Paper E) A precoding scheme that is more suitable when only the channel statistics are available at the users, referred to as enhanced normalized CB. It consists in normalizing the precoding vector by its squared norm in order to reduce the fluctuations of the effective channel seen at the user, and thereby to boost the channel hardening. The performance achieved by this scheme is compared with the CB scheme with DL training (described in Paper D). Paper F) A maximum-likelihood-based method to estimate the channel statistics in the UL, along with an accompanying pilot transmission scheme, that is particularly useful in line-of-sight operation and in scenarios with resource constraints. Pilots are structurally phase-rotated over different coherence blocks to create an effective statistical distribution of the received pilot signal that can be efficiently exploited by the AP when performing the proposed estimation method. The overall conclusion is that cell-free massive MIMO is not a utopia, and a practical, distributed, scalable, high-performance system can be implemented. Today it represents a hot research topic, but tomorrow it might represent a key enabler for beyond-5G technology, as massive MIMO has been for 5G. La quinta generazione dei sistemi radiomobili cellulari (5G) è oggi una realtà. Le reti 5G si stanno diffondendo in tutto il mondo e i dispositivi 5G (ad esempio smartphones, tablets, indossabili, ecc.) sono già disponibili sul mercato. I sistemi 5G garantiscono livelli di connettività e di qualità di servizio senza precedenti, per fronteggiare l’incessante crescita del numero di dispositivi connessi alla rete e della domanda di dati ad alta velocità. La tecnologia Massive MIMO (multiple-input multiple-output) riveste un ruolo fondamentale nei sistemi 5G. Il principio alla base di questa tecnologia è l’impiego di un elevato numero di antenne collocate nella base station (stazione radio base) le quali trasmettono/ricevono segnali, in maniere coerente, a/da più terminali utente. Questo co-processamento del segnale da parte di più antenne apporta molteplici benefici: guadagno di array, diversità spaziale e multiplazione degli utenti nel dominio spaziale. Questi elementi consentono di raggiungere i requisiti di servizio stabiliti per i sistemi 5G. Tuttavia, il limite principale dei sistemi massive MIMO, così come di ogni rete cellulare, è rappresentato dalla interferenza inter-cella (ovvero l’interferenza tra aree di copertura gestite da diverse base stations), la quale riduce in modo significativo le performance degli utenti a bordo cella, già degradate dalle attenuazioni del segnale dovute alla considerevole distanza dalla base station. Per superare queste limitazioni e fornire una qualità del servizio uniformemente eccellente a tutti gli utenti, è necessario un approccio più radicale e guardare oltre il classico paradigma cellulare che caratterizza le attuali architetture di rete. A tal proposito, cell-free massive MIMO (massive MIMO senza celle) costituisce un cambio di paradigma: ogni utente è circondato e servito contemporaneamente da numerose, semplici e di dimensioni ridotte base stations, denominate access points (punti di accesso alla rete). Gli access points cooperano per servire tutti gli utenti nella loro area di copertura congiunta, eliminando l’interferenza inter-cella e il concetto stesso di cella. Non risentendo più dell’effetto “bordo-cella”, gli utenti possono usufruire di qualità di servizio e velocità dati eccellenti. Sebbene attraente dal punto di vista delle performance, l’implementazione di un tale sistema distribuito è una operazione impegnativa ed è oggetto di questa tesi. Piu specificatamente, questa tesi di dottorato tratta: Articolo A) L’enorme potenziale di questa promettente tecnologia in scenari realistici sia indoor che outdoor, proponendo anche delle soluzioni di implementazione flessibili ed a basso costo. Articolo B) Come preservare la scalabilità del sistema, proponendo soluzioni distribuite riguardanti il processamento e la condivisione dei dati, l’architettura di rete e l’allocazione di potenza, ovvero come ottimizzare i livelli di potenza trasmessa dagli access points per ridurre l’interferenza tra utenti e migliorare le performance. Articolo C) Come migliorare l’efficienza spettrale in downlink (da access point verso utente) proponendo due schemi di pre-codifica dei dati di trasmissione, denominati local partial zero-forcing (ZF) e local protective partial ZF, che forniscono un perfetto compromesso tra cancellazione dell’interferenza tra utenti ed amplificazione del segnale desiderato. Articolo D) Come migliorare l’efficienza spettrale in downlink permettendo al terminale utente di stimare le informazioni sulle condizioni istantanee del canale da sequenze pilota, piuttosto che basarsi su informazioni statistiche ed a lungo termine, come convenzionalmente previsto. Articolo E) In alternativa alla soluzione precedente, uno schema di pre-codifica che è più adatto al caso in cui gli utenti hanno a disposizione esclusivamente informazioni statistiche sul canale per poter effettuare la decodifica dei dati. Articolo F) Un metodo per permettere agli access points di stimare, in maniera rapida, le condizioni di canale su base statistica, favorito da uno schema di trasmissione delle sequenze pilota basato su rotazione di fase. Realizzare un sistema cell-free massive MIMO pratico, distribuito, scalabile e performante non è una utopia. Oggi questo concept rappresenta un argomento di ricerca interessante, attraente e stimolante ma in futuro potrebbe costituire un fattore chiave per le tecnologie post-5G, proprio come massive MIMO lo è stato per il 5G. Den femte generationens mobilkommunikationssystem (5G) är numera en verklighet. 5G-nätverk är utplacerade på ett flertal platser världen över och de första 5G-kapabla terminalerna (såsom smarta telefoner, surfplattor, kroppsburna apparater, etc.) är redan kommersiellt tillgängliga. 5G-systemen kan tillhandahålla tidigare oöverträffade nivåer av uppkoppling och servicekvalitet och är designade för en fortsatt oavbruten tillväxt i antalet uppkopplade apparater och ökande datataktskrav. Massiv MIMO-teknologi (eng: multiple-input multiple-output) spelar en nyckelroll i dagens 5G-system. Principen bakom denna teknik är användningen av ett stort antal samlokaliserade antenner vid basstationen, där alla antennerna sänder och tar emot signaler faskoherent till och från flera användare. Gemensam signalbehandling av många antennsignaler ger ett flertal fördelar, såsom hög riktverkan via lobformning, vilket leder till högre datatakter samt möjliggör att flera användare utnyttjar samma radioresurser via rumslig användarmultiplexering. Eftersom en signal kan gå genom flera olika, möjligen oberoende kanaler, så utsätts den för flera olika förändringar samtidigt. Denna mångfald ökar kvaliteten på signalen vid mottagaren och förbättrar radiolänkens robusthet och tillförlitlighet. Detta gör det möjligt att uppfylla de höga kraven på servicekvalitet som fastställts för 5G-systemen. Den största begränsningen för massiva MIMO-system såväl som för alla cellulära mobilnätverk, är störningar från andra celler som påverkar användare på cellkanten väsentligt, vars prestanda redan begränsas av sträckdämpningen på radiokanalen. För att övervinna dessa begränsningar och för att kunna tillhandahålla samma utmärkta servicekvalitet till alla användare behöver vi ett mer radikalt angreppssätt: vi måste utmana cellparadigmet. I detta avseende utgör cellfri massiv-MIMO teknik ett paradigmskifte. I cellfri massive-MIMO är utgångspunkten inte att basstationen är omgiven av användare som den betjänar, utan snarare att varje användare omges av basstationer som de betjänas av. Dessa basstationer, ofta mindre och enklare, kallas accesspunkter (AP). I ett sådant system upplever varje användare att den befinner sig i centrum av systemet och ingen användare upplever några cellgränser. Därav terminologin cellfri. Som ett resultat av detta påverkas inte användarna av inter-cellstörningar och sträckdämpningen reduceras kraftigt på grund av närvaron av många accesspunkter i varje användares närhet. Detta leder till imponerande prestanda. Även om det är tilltalande ur ett prestandaperspektiv så är utformningen och implementeringen av ett sådant distribuerat massivt MIMO-system en utmanande uppgift, och det är syftet med denna avhandling att studera detta. Mer specifikt studerar vi i denna avhandling: A) den mycket stora potentialen med denna teknik i realistiska inomhus- såväl som utomhusscenarier, samt hur man hanterar praktiska implementeringsproblem, såsom klocksynkronisering bland accesspunkter och kostnadseffektiva implementeringar; B) hur man ska uppnå skalbarhet i systemet genom att föreslå lösningar relaterade till databehandling, nätverkstopologi och effektkontroll; C) hur man ökar datahastigheten i nedlänken med hjälp av två nyutvecklade distribuerade överföringsmetoder som tillhandahåller en avvägning mellan störningsundertryckning och förstärkning av önskade signaler, utan att öka mängden intern signalering till de distribuerade accesspunkterna, och som kan implementeras i accesspunkter med mycket få antenner; D) hur man kan förbättra prestandan ytterligare genom att låta användaren estimera nedlänkskanalen med hjälp av nedlänkspiloter, istället för att bara förlita sig på kunskap om kanalstatistik; E) en överföringsmetod för nedlänk som är mer lämpligt när endast kanalstatistiken är tillgänglig för användarna. Prestandan som uppnås genom detta schema jämförs med en utökad variant av den nedlänk-pilotbaserade metoden (beskrivet i föregående punkt); F) en metod för att uppskatta kanalstatistiken i upplänken, samt en åtföljande pilotsändningsmetod, som är särskilt användbart vid direktvägsutbredning (line-of-sight) och i scenarier med resursbegränsningar. Den övergripande slutsatsen är att cellfri massiv MIMO inte är en utopi, och att ett distribuerat, skalbart, samt högpresterande system kan implementeras praktiskt. Idag representerar detta ett hett forskningsämne, men snart kan det visa sig vara en viktig möjliggörare för teknik bortom dagens system, på samma sätt som centraliserad massiv MIMO har varit för de nya 5G-systemen.

Download or read book Challenges and Risks Involved in Deploying 6G and NextGen Networks written by Bharathy, A.M. Viswa and published by IGI Global. This book was released on 2022-06-24 with total page 258 pages. Available in PDF, EPUB and Kindle. Book excerpt: There is a need to be aware of the challenges awaiting us in next generation (NextGen) networks in order to take the proper steps to either minimize or eliminate issues as they present themselves. Incorporating artificial intelligence in NextGen networks for privacy and security policies will serve this purpose. It is essential to stay current with these emerging technologies and applications in order to maintain safe and secure communications in the future. Challenges and Risks Involved in Deploying 6G and NextGen Networks explores strategies for the design and deployment of more secured and user-centered NextGen networks through artificial intelligence to enrich user experience. It further investigates the political, social, and geographical challenges involved in realizing these 6G networks and explores ways to improve the security of future potential applications as well as protect user data from illegal access. Covering topics such as deep learning algorithms, aerial network communication, and edge computing, this major reference work is an indispensable resource for regulatory and policy groups, associations and technology groups, government and international bodies, technology executives and technical institutions, management consulting and advisory firms, communication engineers, network engineers, students and educators of higher education, researchers, and academicians.

Download or read book Fundamentals of 5G Communications Connectivity for Enhanced Mobile Broadband and Beyond written by Wanshi Chen and published by McGraw Hill Professional. This book was released on 2021-07-23 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt: Explore the foundations and applications of 5G technology This comprehensive guide contains practical information from telecommunications experts working at the forefront of 5G innovation. The authors discuss the foundations of 5G technology―not just the new standards, but the reasons and stories behind them. Fundamentals of 5G Communications features coverage of all major vertical domains with a focus on practical, commercial applications. This book serves both as an essential reference for telecom professionals and as a textbook for students learning about 5G. Coverage includes: 5G versus 4G: What’s new? Deployment scenarios and architecture options The evolution of 5G architecture Numerology and slot structure Initial access and mobility Downlink control and data operation Uplink control and data operation Coexistence of 4G and 5G 5G in unlicensed and shared spectra Vertical expansion: URLLC, MTC, V2X Vertical expansion: broadcast and multicast Typical 5G commercial deployments A look toward the future of 5G