Channel Title: Wireless Future Channel Description: Wireless Future is a channel by Emil Björnson (Professor at KTH Royal Institute of Technology) and Erik G. Larsson (Professor at Linköping University), both IEEE Fellows and Clarivate Highly Cited Researchers. The channel focuses on wireless communications and its applications. It contains a combination of podcast episodes, popular science material, tutorial videos, lecture material from university courses, and technical presentations related to recent research. Some recurring themes are Cellular and Cell-free Massive MIMO, reconfigurable intelligent surfaces (a.k.a. intelligent reflecting surfaces), 5G, and 6G. <video> Introduction to Multiple Antenna Communications and Reconfigurable Surfaces Description: Professor Emil Björnson explains why he wrote the open-science book "Introduction to Multiple Antenna Communications and Reconfigurable Surfaces" together with Özlem Tuğfe Demir. In particular, he answers the questions: What is covered by the book? Who is the book written for? Where can I get the book? You can download the PDF for free from: https://www.nowpublishers.com/article/BookDetails/9781638283140 The simulation code is available at https://github.com/emilbjornson/mimobook Book description: Wireless communication is the backbone of the digitized society, where everything is connected and intelligent. Access points and devices are nowadays equipped with multiple antennas to achieve higher data rates, better reliability, and support more users than in the past. This book gives a gentle introduction to multiple antenna communications with a focus on system modeling, channel capacity theory, algorithms, and practical implications. The basics of wireless localization, radar sensing, and controllable reflection through reconfigurable surfaces are also covered. The goal is to provide the reader with a solid understanding of this transformative technology that changes how wireless networks are designed and operated, today and in the future. The first three chapters cover the fundamentals of wireless channels, and the main benefits of using multiple antennas are identified: beamforming, diversity, and spatial multiplexing. The theory and signal processing algorithms for multiple-input multiple-output (MIMO) communications with antenna arrays at the transmitter and receiver are progressively developed. The next two chapters utilize these results to study point-to-point MIMO channels under line-of-sight (LOS) and non-LOS conditions, covering the shape of signal beams, impact of array geometry, polarization, and ways to achieve reliable communication over fading channels. The book then shifts focus to multi-user MIMO channels, where interference between devices is managed by spatial processing. The next chapter extends the theory to multicarrier channels and explains practical digital, analog, and hybrid hardware implementations. The last two chapters cover the role of multiple antennas in localization and sensing, and how reconfigurable surfaces can improve both communication and sensing systems. The text was developed as the textbook for a university course and builds on the reader's previous knowledge of signals and systems, linear algebra, probability theory, and digital communications. Each chapter contains numerous examples, exercises, and simulation results that can be reproduced using accompanying code. The accompanying code and material is available at https://github.com/emilbjornson/mimobook </video> <video> 6G: What, why, and how? Description: Professor Emil Björnson (KTH Royal Institute of Technology) overviews the 6G technology development. He begins by explaining what cellular/mobile communication networks are and how their characteristics and services have evolved over the last five generations. He then describes why we need 6G and what it might be used for during the next decade. Next, he explains how the 6G standard is developed through an interplay between the research community, 3GPP, and ITU. Finally, he describes the anticipated IMT-2020 scenarios and requirements and what frequency spectrum will be utilized in 6G networks. The slides are available here: https://github.com/emilbjornson/presentation_slides/blob/master/6G_when_why_how.pdf </video> <video> Ep 39. Radio Stripes at Terahertz (With Parisa Aghdam) [Wireless Future Podcast] Description: Massive bandwidths are available in the sub-terahertz bands, but the coverage of a cellular network exploiting those frequencies will be spotty. The 6GTandem project tries to circumvent this issue by developing a dual-frequency system architecture that jointly uses the sub-6 GHz and sub-THz bands. In this episode, Erik G. Larsson and Emil Björnson are visited by Dr. Parisa Aghdam, Technical Lead of 6GTandem and Research Manager at Ericsson. The discussion starts with potential use cases, such as extended reality services in stadiums and connected factories. The conversation then focuses on hardware aspects, such as how to build a distributed antenna system using plastic microwave fibers and amplifiers so that sub-THz signals can be transmitted from many different locations. You can read more about the EU-funded project and its partners at https://horizon-6gtandem.eu/ Music: On the Verge by Joseph McDade. Visit Erik’s website https://liu.se/en/employee/erila39 and Emil’s website https://ebjornson.com/ You can listen to the audio-only podcast at the following places: Apple Podcasts: https://podcasts.apple.com/se/podcast/wireless-future/id1536090689 Google Podcasts: https://podcasts.google.com/feed/aHR0cHM6Ly9mZWVkLnBvZGJlYW4uY29tL3dpcmVsZXNzZnV0dXJlL2ZlZWQueG1s Spotify: https://open.spotify.com/show/0RDeni3rDUx5HnZWJGACqO #wireless #wirelessfuture #6g #terahertz #radiostripes #ericsson </video> <video> Ep 40. Synchronization of Massive Antenna Arrays [Wireless Future Podcast] Description: Many textbook models of communication systems assume that the transmitter and receiver are synchronized in time, frequency, and phase. Achieving and maintaining such synchronization is an often-overlooked practical challenge. However, the importance of synchronization grows as we plan to use larger antenna arrays and distributed MIMO in 6G. In this episode, Emil Björnson and Erik G. Larsson discuss some fundamental principles of synchronization, including the underlying physical phenomena, pilot signaling for phase synchronization, and reciprocity calibration. We especially discuss how the seemingly simplest angular beamforming can be among the hardest features to support from a synchronization perspective, with a digital array. More technical details in the papers https://arxiv.org/abs/2304.05144 and https://arxiv.org/abs/2401.11730 Music: On the Verge by Joseph McDade. Visit Erik’s website https://liu.se/en/employee/erila39 and Emil’s website https://ebjornson.com/ You can listen to the audio-only podcast at the following places: Apple Podcasts: https://podcasts.apple.com/se/podcast/wireless-future/id1536090689 Google Podcasts: https://podcasts.google.com/feed/aHR0cHM6Ly9mZWVkLnBvZGJlYW4uY29tL3dpcmVsZXNzZnV0dXJlL2ZlZWQueG1s Spotify: https://open.spotify.com/show/0RDeni3rDUx5HnZWJGACqO #wireless #wirelessfuture #6g #synchronization #mimo #reciprocity </video> <video> Reconfigurable Intelligent Surfaces Through the Lens of Array Signal Processing Description: Recording of the keynote speech that Prof. Emil Björnson delivered at the IEEE CAMSAP 2023 (https://camsap23.ig.umons.ac.be) and IEEE SITB 2024 (https://sites.google.com/view/sitb2024/). Abstract: Wireless communication systems have traditionally been designed to operate under the channel conditions provided by nature, with the Shannon capacity being the ultimate limit. The advent of reconfigurable intelligent surfaces (RIS) changes the status quo by adding the ability to control wave propagation, thereby modifying the capacity. A RIS is an array of reflecting elements with properties that can be tuned to synthesize the reflection behavior of a differently shaped object. The larger the surface is, the greater performance improvements are possible. The gains are achieved by adapting the RIS configuration to the channel coefficients from the transmitter to the receiver via the RIS, which must be estimated in practice. The estimation challenge grows with the number of reflecting elements, in terms of the signal resources required for pilot signaling. The problem differs from the classical estimation problems in multi-antenna communications because the RIS is blind and substantially larger. Hence, the estimation dimensionality might be the showstopper for practical RIS deployments. In this talk, we will look at how array signal processing theory provides suitable tools to describe and analyze RIS-aided communication systems. We will explore how these tools enable us to model the physical channels and discover how to simplify the channel estimation problem by exploiting fundamental properties, such as the array geometry, array responses, and channel geometry. It turns out that, under the right circumstances, array processing methodology can solve the estimation challenge. The talk will end with an outlook on unsolved showstoppers for RIS technology. The slides can be downloaded here: https://github.com/emilbjornson/presentation_slides/blob/master/RIS_array_signal_processing.pdf </video> <video> 6G kräver många fler antenner än idag - så ska det gå till! [English version exists] Description: There is a version with English subtitles: https://youtu.be/kOC0TOZmh4g Beskrivning: För att 6G, framtidens teknik för mobilnäten, ska fungera krävs det många antenner. Det kan till exempel ske genom att sätta upp remsor med små antenner. Emil Björnson och hans forskargrupp på KTH utvecklar tekniken med hjälpa av avancerade beräkningsalgoritmer. Filmen är skapad av Stiftelsen för Strategisk forskning,@ssfstiftelsen </video> <video> Ep 38. Things We Learned at the 6G Symposium [Wireless Future Podcast] Description: Many topics are studied within the 6G research community, from hardware design to algorithms, protocols, and services. Erik G. Larsson and Emil Björnson recently attended the ELLIIT 6G Symposium in Lund, Sweden. In this episode, they discuss ten things that they learned from listening to the keynote speeches. The topics span from integrated sensing, positioning, and localization via machine-learning applications in communications to fundamental communication theory, such as circuits for universal channel decoding and jamming protection. The expected 6G spectrum ranges, energy efficiency in base stations, and new use cases for electromagnetic materials are also covered. You can find slides from the symposium at https://elliit.se/news-and-events/focus-period-lund-2023/ Music: On the Verge by Joseph McDade. Visit Erik’s website https://liu.se/en/employee/erila39 and Emil’s website https://ebjornson.com/ Chapters: 3:22 Integrated sensing and communication 12:45 Positioning using phase-coherent access points 20:42 Experimental work on positioning from ELLIIT Focus period 24:02 Trained activation functions in machine learning 30:25 Learning to operate a reconfigurable intelligent surface 37:15 Guessing Random Additive Noise Decoding (GRAND) 44:30 Protecting digital beamforming against jamming 53:02 6G frequency spectrum 1:01:50 Energy efficiency in base stations 1:08:47 New use cases for electromagnetic materials You can listen to the audio-only podcast at the following places: Apple Podcasts: https://podcasts.apple.com/se/podcast/wireless-future/id1536090689 Google Podcasts: https://podcasts.google.com/feed/aHR0cHM6Ly9mZWVkLnBvZGJlYW4uY29tL3dpcmVsZXNzZnV0dXJlL2ZlZWQueG1s Spotify: https://open.spotify.com/show/0RDeni3rDUx5HnZWJGACqO #wireless #wirelessfuture #6g #GRAND #jamming #energyefficiency #spectrum </video> <video> Three Misconceptions in Near-Field Communications Description: This is a recording of Professor Emil Björnson's invited talk in the "Special Forum: Theory and Technology of 6G Near-Field Communications" at the 17th China Electronics & Information Conference. This hybrid event took place at the Pan Pacific Hotel, Ningbo, on April 27, 2024. Abstract: The attempts to use mmWave bands in cellular networks have largely failed. The latest example is South Korea, which closed its networks in 2023. As we are running out of spectrum suitable for wide-area connectivity, we must search for alternative ways to cater to the exponential traffic growth. Long-range near-field communication is one potential paradigm shift that can be utilized to manage more traffic in next-generation wireless networks without the need for more spectrum. Near-field technology could potentially provide new spatial degrees of freedom and unprecedented beamfocusing capabilities, as well as change how wireless channels behave. After five years of research, I remain a stronger believer in this technology, which challenges how we build, operate, and evaluate communication performance. However, not everything is as different and wonderful as it seems. In this talk, I will describe three fundamental properties of the technology and correct common misconceptions related to them. </video> <video> 6G requires many more antennas than today - this is how it will work! Description: Many antennas are required to get 6G, the future technology for mobile networks, to work properly. This can be done, for example, by setting up strips with small antennas. Emil Björnson and his research group at KTH develop the technology with the help of advanced calculation algorithms. Watch the movie with one of SSF's Future Research Leaders 7! The video is recorded by the Swedish Foundation for Strategic Research @ssfstiftelsen </video> <video> User-Centric Cell-Free Massive MIMO: From Foundations to Scalable Implementation [3h tutorial] Description: This tutorial was recorded for the IEEE PIMRC 2021 conference and was presented by Emil Björnson, Luca Sanguinetti, and Özlem Tugfe Demir. It is based on the open-access textbook "Foundations of User-Centric Cell-Free Massive MIMO", which can be downloaded here: https://github.com/emilbjornson/cell-free-book The slides used in the tutorial can be downloaded here: https://github.com/emilbjornson/presentation_slides/blob/master/cellfree-tutorial-PIMRC2021.pdf Abstract: As the first 5G commercial networks have been launched, it is time to look for new forward-looking research directions that have the potential to revolutionize the future of wireless. Just as the seminal papers on Massive MIMO were published 10 years ago (2010), this is likely the time (2021) when the key technology components for 6G will be identified. Hence, this is the right time for researchers to discover new research directions and potentially find the next big thing. In this tutorial, we will first go through the foundations of the original Cell-Free Massive MIMO, which is a recently proposed alternative infrastructure to overcome the key weaknesses of cellular systems. The first papers in this area are just a few years old and there are still many open problems. One important issue with the original form of Cell-Free Massive MIMO is scalability, which is one of the key topics that we will cover in this tutorial as well as possible solutions such as user-centric dynamic cooperation clustering. We will describe different methods for signal processing and spatial resource allocation, including optimized techniques and scalable heuristics solutions. After providing some implementation constraints, we will discuss open problems related to this research direction. </video> <video> Ep 37. Wireless Future Panel Discussion (Live Podcast) [Wireless Future Podcast] Description: We celebrate the three-year anniversary of the podcast with a live recording from the Wireless Future Symposium that was held in September 2023. A panel of experts answered questions that we received on social media. Liesbet Van der Perre (KU Leuven) discusses the future of wireless Internet-of-Things, Fredrik Tufvesson (Lund University) explains new channel properties at higher frequencies, Jakob Hoydis (NVIDIA) describes differentiable ray-tracing and its connection to machine learning, Deniz Gündüz (Imperial College London) presents his vision for how artificial intelligence will affect future wireless networks, Henk Wymeersch (Chalmers University of Technology) elaborates on the similarities and differences between communication and positioning, and Luca Sanguinetti (University of Pisa) demystifies holographic MIMO and its relation to near-field communications. Music: On the Verge by Joseph McDade. Visit Erik’s website https://liu.se/en/employee/erila39 and Emil’s website https://ebjornson.com/ You can listen to the audio-only podcast at the following places: Apple Podcasts: https://podcasts.apple.com/se/podcast/wireless-future/id1536090689 Google Podcasts: https://podcasts.google.com/feed/aHR0cHM6Ly9mZWVkLnBvZGJlYW4uY29tL3dpcmVsZXNzZnV0dXJlL2ZlZWQueG1s Spotify: https://open.spotify.com/show/0RDeni3rDUx5HnZWJGACqO #wireless #wirelessfuture #6g </video> <video> Bit Error Ratio or Channel Capacity: Which metric should I use? [Frequently Asked Questions] Description: Professor Emil Björnson (KTH, Sweden) answers the question "Bit Error Ratio (BER) or Channel Capacity: Which metric should I use?", which he has received repeatedly in emails, on his blog, and in comments on this YouTube channel. The background to the question is that the BER is often considered in basic communication textbooks, while research papers often consider the capacity metric. The short answer is that practical systems are designed to achieve a very small BER; thus, the important thing is how many bits per second can be transferred while achieving that. The channel capacity is a good predictor of that. Emil explains these basic concepts in an accessible manner. Intro music: Quiet Calculation by Joseph McDade. </video> <video> 6G in the Upper Mid-Band: The Rise of Gigantic MIMO Description: For the last five years, most of the research into wireless communications has been motivated by its potential role in 6G. After this exploratory phase, it is time to identify which new technology components will make it into the standard and eventually into practical networks. It has recently become clear that 6G networks will operate in the upper mid-band from 7 to 25 GHz, which has been called the "golden band" since it offers more spectrum than current 5G networks in the 3.5 GHz band and much better propagation conditions than at mmWave frequencies. The most interesting new frequency range is around 7.8 GHz, where 650-1275 MHz of spectrum might become available, depending on the country. This might seem like a lot, but it is far from enough to reach the ambitious 6G requirements defined by the International Telecommunications Union. For 6G to deliver on its promises, we also need a leap in the antenna technology - from "Massive MIMO" in 5G to "Gigantic MIMO" in 6G. In this video, Professor Emil Björnson explains the anticipated development with a focus on how many antenna elements we need to overcome the pathloss challenge, how to reach the theoretical peak bit rates, how to achieve impressive typical rates using spatial multiplexing, and how to utilize radiative near-field propagation effects for more precise communication, localization, and sensing. He also identifies four open research areas where new contributions have good prospects to affect the actual 6G technology implementation. This talk was first delivered at the NGMA-ETI 2nd QMUL ‘6G’ Workshop, Queen Mary University of London, July 11, 2024. The slides are available here: https://github.com/emilbjornson/presentation_slides/blob/master/6G_gigantic_MIMO.pdf If you want to learn more, we recommend the following article: Emil Björnson, Ferdi Kara, Nikolaos Kolomvakis, Alva Kosasih, Parisa Ramezani, and Murat Babek Salman, “Enabling 6G Performance in the Upper Mid-Band Through Gigantic MIMO,” arXiv:2407.05630. https://arxiv.org/pdf/2407.05630 </video> <video> How many beams can you send from a MIMO array? [Frequently Asked Questions] Description: Professor Emil Björnson (KTH, Sweden) answers the question "How many beams can you send from a MIMO array?", which he has received repeatedly in emails, on his blog, and in comments on this YouTube channel. The answer is not what you think it is, unless we reformulate the question. Emil illustrates and explains the basic concepts in an accessible manner. Intro music: Quiet Calculation by Joseph McDade. </video> <video> What is the Role of AI in 6G Networks? [Frequently Asked Questions] Description: Professor Emil Björnson (KTH, Sweden) answers the question "What is the Role of AI in 6G Networks?", which he has received repeatedly in emails, on his blog, and in comments on this YouTube channel. The background to the question is that artificial intelligence and machine learning tools have become so popular that we tend to assume they will revolutionize all parts of society. Does this also apply to wireless technology, and in which situations can we expect the largest improvements? Emil provides his best answer to these questions, which culminates in three main opportunities and three main challenges. The video was recorded in January 2024 and is based on Emil's introductory speech in a panel discussion at EuCNC 2023. Intro music: Quiet Calculation by Joseph McDade. </video>

Contacts and Links

Description

Wireless Future is a channel by Emil Björnson (Professor at KTH Royal Institute of Technology) and Erik G. Larsson (Professor at Linköping University), both IEEE Fellows and Clarivate Highly Cited Researchers. The channel focuses on wireless communications and its applications. It contains a combination of podcast episodes, popular science material, tutorial videos, lecture material from university courses, and technical presentations related to recent research. Some recurring themes are Cellular and Cell-free Massive MIMO, reconfigurable intelligent surfaces (a.k.a. intelligent reflecting surfaces), 5G, and 6G.

Videos from channel