IEEE ComSoc Emerging Technology InitiativeBackhaul/fronthaul Networking & Communications

(ETI-BNC) Blog

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 1

Contents

1 Chair’s Message 2

2 Editor Biographies - Feature Topic 4

3 Introduction to the Feature Topic 5

4 Review Paper 1: IEEE Comm Mag 7

5 Review Paper 2: IEEE TWC 9

6 IEEE ETI-BNC Online Panel 2019 11

7 Call for Papers: IEEE JSAC 12

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 2

Chair’s Message

Muhammad Zeeshan Shakir

University of the West of Scotland, Scotland, Email: muhammad.shakir@uws.ac.uk

Dear Members:

I am glad to distribute third issue of IEEE ETI-BNC Blog. In this issue, I would like to present ourETIs progress from past 4 years to demonstrate thecontribution of our ETI to the technical areas. Thisissue also includes feature topic self-backhaulingedited by Dr. Omid Semiari from Georgia SouthernUniversity, Dr. Syed Ali Raza Zaidi from Universityof Leeds and Dr. Abdellah Chehri from Universityof Quebec much thanks for their continued supportto our ETI and members. You will also find call forparticipation to our ETIs Online meeting to be heldon July 1, 2019 where we will present panel discus-sions on the use of flying platforms for future accessand backhaul networks. Please find more detail here.You are also invited to contribute to JSAC SpecialIssue on Industry 4.0 with deadline currently set asJuly 1, 2019. For more future activities visit our web-site.

You know that our ETI-BNC has been a forumfor industrial and academic researchers and prac-titioners to identify and discuss the wireless back-haul/fronthaul requirements for emerging technolo-gies and smart cities, associated challenges, recentdevelopment and smart end-to-end solutions per-taining to fifth-generation (5G) and beyond of mo-

bile communication networks and ad hoc networks.ETI-BNC has provided a prolific opportunity to ed-ucate about, promote and accelerate the evolutionof next generation of backhaul/fronthaul networkingand communications by fostering a variety of techni-cal activities in the related area.

I am glad to say that with over 120 active mem-bers (doubled since early 2017 and mostly indus-trial members) ETI-BNC community has grown verymuch since recently. ETI has been organizing techni-cal activities with consistency. So far, our membershave organized 12 workshops/conference with IEEEBackNets alone published over 40 articles in IEEEGCC/ICC workshop proceedings over past 4 years;7 Special Issues (JSAC, Communications Magazine,Access and Wireless Communications and Trans.Cognitive Communications); 3 Online newsletters;and 5 tutorials with very much active participationfrom industry to bridge the research and develop-ment of cross-cutting technologies for future smartbackhaul and fronthaul networking, communicationsand signal processing. Recently, our ETI has pub-lished IEEE ComSoc Best Reading List: Backhauland Fronthaul: Communications, Networking andSignal Processing, edited by myself, Prof Muham-mad Imran from University of Glasgow and Prof

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 3

Walid Saad from VTech which is expected to provideseveral archival papers and other online resourceson the backhaul/fronthaul and related networking,communication, and signal processing issues that areuseful if you are doing research in this area or ex-pected to build interest in this area. Stay tuned toour News and Activity sections for future events andactivities and continue to participate in the ETIs ac-tivities in future.

Recently, our ETI-BNC has been evaluated by ETIChair and members as part of IEEE ComSoc rulesand policies. Our ETI has received positive feedbackfrom the review panel. Some of the important feed-back includes improvement of our members in fol-lowing aspects of our organization and participationin ComSoc-wide activities:

• To broaden the participation from our membersacross academia and industry to our ongoingprograms and activities

• To make effective measures for interaction withrelevant standardization bodies.

For now, ETI-BNC will continue as ETI until nextreview cycle. As always, I welcome your sugges-tions and comments to improve involvement and par-ticipation from ETI-BNC members and also wouldlike to invite you all to attend our next Online meet-ing to be held on July 1, 2019.

At the end as usual, a final reminder - the blogaims to highlight key achievements of commu-nity members. Consequently, if you would liketo share your recent achievements or highlightsuccessful proposal which are of relevance to thecommunity, please get in touch with the editors.I would like to take this opportunity to welcomeany suggestions from the community membersto make ETI-BNC blog more informative andinteresting. You are welcome to either write to me atmuhamamd.shakir@uws.ac.uk or approach any of

the editors.

Best regards,Muhammad Zeeshan ShakirChair IEEE ComSoc ETI-BNC

Muhammad Zeeshan Shakir isReader at the University of theWest of Scotland (UWS), UK.At UWS, he has been investigat-ing commercial / non-commercialresearch projects in the areasof wireless communications ofworth more than 900k funded by

bodies such as Innovate UK, EU programmes suchas ERASMUS and matched by UK industries. Re-cently, he has been awarded with UWS STARS(Staff Appreciation and Recognition Scheme) award2018 for Outstanding Research and Enterprise per-formance at UWS. Before joining UWS, he hasworked at Carleton University, Canada, Texas AMUniversity, Qatar and KAUST, Saudi Arabia on var-ious RD projects. He has published more than 100technical journal and conference papers and has con-tributed to 12 books, all in reputable venues. Hehas been/is serving as a Chair of several sympo-siums/workshops in IEEE flagship conferences, in-cluding Globecom, ICC and VTC. He is an Editorof PHYCOM, IEEE Communications, IEEE Com-munications Letters, IEEE Wireless Communica-tions and IEEE Access. He is a founding Chairof IEEE ComSoc emerging technical committee onbackhaul/fronthaul. He is a Senior Member of IEEEand an active member of IEEE ComSoc.

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 4

Feature Topic Editors: Self-Backhauling in 5Gand Beyond Cellular Networks

Omid Semiari and Syed Ali Raza Zaidi

osemiari@georgiasouthern.edu, s.a.zaidi@leeds.ac.uk

This issue presents self-backhauling as featuretopic for future backhaul and fronthaul networks. Wethank Dr. Abdellah Chehri form University of Que-bec, Canada for presenting two interesting reviewson recently publsihed articles for ETI members tohighlight key challenges for MIMO and mm-wavebased self-backhauling systems. We would like towelcome any suggestions for our future issues. Wealso welcome reviews for future articles.

Omid Semiari is an AssistantProfessor at the Department ofElectrical and Computer Engi-neering at Georgia Southern Uni-versity. He received the BS andMS degrees in electrical engineer-ing from the University of Tehran,in 2010 and 2012, respectively,and the PhD degree from Vir-ginia Tech, in 2017. His re-

search interests include wireless networks, millime-ter wave communications, ultra-reliable and low-latency communications, context-aware networks,matching theory, and applied machine learning. In2014, Dr. Semiari has worked as a research internat Bell Labs, in Stuttgart, on anticipatory, context-aware resource management in cellular networks. In

2016, he has joined Qualcomm CDMA Technologiesfor a summer internship, working on LTE-Advancedmodem design. Dr. Semiari is the recipient of severalresearch fellowship awards, including DAAD (Ger-man Academic Exchange Service) scholarship andNSF student travel grant. He has actively served as areviewer for flagship IEEE Transactions and confer-ences and participated as the technical program com-mittee (TPC) member for a variety of workshops atIEEE conferences.

Syed Ali Raza Zaidi Dr SyedAli Raza Zaidi is currently a Uni-versity Academic Fellow (Assis-tant Professor) in the broad areaof Communication and Sensingfor RAS. He was awarded J. W.and F. W. Carter Prize, was alsoawarded with COST IC0902, EP-

SRC, DAAD and Royal Academy of Engineeringgrants. He has published more than 95 technicalpapers in various top-tier IEEE Journals and confer-ences. His research interests include design and im-plementation of communication protocols for wire-less networking specifically in the area of M2M.

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 5

Feature Topic: Self-Backhauling in NextGeneration Wireless Cellular Networks

Author: Abdellah Chehri

University of Quebec in Chicoutimi, Canada, Email: achehri@uqac.ca

Wireless communication has gone throughdecades of thriving advances. Compared to fourth-generation (4G) cellular systems, fifth-generation(5G) wireless communication systems face anever-increasing demand for spectral efficiency andhigh data rates as required by new devices and ap-plications. To meet the growing data traffic volumea number of emerging technologies are currentlyinvestigated. The idea of enhancing the capacity canbe achieved by: 1) a higher frequency spectrum (e.g.,mmWave), or by 2) advanced spectral-efficiencytechniques such as massive MIMO and efficientmodulation schemes or by 3) reducing the cell sizethrough an ultra-dense small cell deployment [1].

This densification involves large numbers of cells,even for LTE, and the numbers will increase in5G because of its increased capacity requirements,higher spectrum bands and support for new servicessuch as smart city applications. Based on researchconducted by the Small Cell Forum, both public andprivate enterprise small cell deployments will see acontinuous growth through 2025 in support of LTEand 5G densification efforts. The industry group seesa peak in LTE small cell deployments around 2020,followed in 2024 by a shift in volume to 5G equip-ment [2].

The typical wired backhaul solution such as op-tical fiber is not always feasible due to the uncon-ventional installation location of small cells and theirincremental unplanned deployment. Therefore vari-ous hybrid backhaul architectures will be needed toaccommodate the cost-efficient, backward compati-ble and dense deployment of network infrastructurewhich is necessary for providing for the broadbandand low latency demands of 5G systems The wirelessschemes employed in these hybrid backhaul solu-tions include self-backhaul [3], multiple-association[4], and millimeter-wave (mmWave) backhaul [5].The wireless backhaul solutions discussed in litera-ture can be categorized as self-backhaul (or in-band)and non-self-backhaul (or out-of-band) [6].

Self-backhaul offers a flexible and cost-efficientsolution as the access and backhaul links share thesame spectrum and have identical radio access tech-nology. These solutions are also referred to as in-band backhaul. The term “in-band” means that theaccess link (BS-MS link) and backhaul link (BS-BSlinks or BS-network links) are multiplexed on thesame frequency band. The capacity and resource al-location between access and backhaul links are ma-jor concerns in self-backhaul solutions, and severalstudies have addressed these issues.

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 6

In this special issue, we focus on self-backhaulingin next generation wireless networks as the featuretopic and overview two key papers in the field.We hope that this effort be useful for our readers,especially to those who are new in this field ofresearch.

References:

[1] T. K. Vu, M. Bennis, S. Samarakoon, M.Debbah, M. Latva-Aho, ”Joint load balanc-ing and interference mitigation in 5G heteroge-neous networks”, IEEE Trans. Wireless Com-mun., vol. 16, no. 9, pp. 6032-6046, Sep. 2017.

[2] Small Cell Forum, [available online]https://www.smallcellforum.org/blog/operator-survey-finds-denser-5g-networks-will-drive-significant-growth-roll-small-cells/

[3] P. Hao, X. Yan, J. Li, Y.N.R. Li, H. Wu,”Flexible resource allocation in 5G ultra densenetwork with self-backhaul, IEEE GlobecomWorkshops, pp. 1-6, San Diego, 2015.

[4] A. Walid, E. Sabir, A. Kobbane, T.Taleb, M.E. Koutbi, ”Exploiting multi-homingin hyper dense LTE small-cells deployments”,IEEE Wireless Communications and Network-ing Conference (WCNC), pp. 1-6 Doha, Qatar,2016.

[5] X. Ge, H. Cheng, M. Guizani, T. Han, ”5Gwireless backhaul networks: challenges andresearch advances”, IEEE Network Magazine,vol. 28, no. 6, pp. 6-11, 2014.

[6] S. Saadat, D. Chen, T. Jiang, ”MultipathMultihop mmwave Backhaul in Ultra DenseSmall Cell Network”, Digital Communicationsand Networks, vol. 4, issue. 2, pp. 111-117,April 2018.

Abdellah Chehri is an assis-tant professor at the Universityof Quebec in Chicoutimi. Hereceived his M.A.Sc. Degreein signal and digital communica-tion from the University Sophia-Antipolis at Nice-France. In Sept.

2004, he joined the department of electrical andcomputer engineering of Laval University, Quebec,Canada. He received his Ph.D. in Electrical Engi-neering in June 2009. From 2007 to 2009, he workedas a project member at the Bell-Aliant Research Lab-oratory, Quebec, Canada and served as a lecturer inthe Information Technologies Graduate Program ofUQAT. He joined the University of Ottawa in July2009 as a postdoctoral fellow and then research asso-ciate. From 2012 to 2014, he was with BLiNQ Net-works where he was involved in the development andtesting of dual-carrier sub-6 GHz backhaul. In Feb2014, he Dr. Chehri worked as a manager of Next-Generation Network (NGN) /VoIP & EmergingTechnologies at Bell Canada. He served as guest edi-tor and severed as a technical reviewer for several in-ternational conferences and journals (IEEE, Elsevier,Springer). Dr. Chehri received many prestigiousawards, including, Deans scholarship award, post-doctoral studies (University Ottawa), a scholarshipfund to support success (Laval University), Japan So-ciety for the Promotion of Science, NSERC postdoc-toral fellowship.

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 7

Review of “Point-to-Multipoint In-Band mmWaveBackhaul for 5G Networks”IEEE Communications Magazine, January 2015

Authors: R. Taori and A. Sridharan

The feasibility of in-band backhaul at mmWavefrequencies was investigated in this work. It wasshown that the access link capacity was not signif-icantly affected by the availability of larger band-widths in a mmWave spectrum. The authors startedtheir investigation by providing a persuasive analy-sis to establish that an in-band backhaul solution atmmWave is feasible. As mentioned previously, inthe in-band wireless backhaul system, the resourcesused for backhaul are taken from the access links re-sources regardless of the multiplexing method used.An important task, therefore, is to analyze whetherenough resources are available for backhauling with-out compromising the access needs.

Based on the deployment scenario and using aMonte Carlo simulation, the cumulative distributionfunction (CDFs) of the instantaneous cell capacitywas calculated. The average link capacities tabu-lated in Fig.1 show that the backhaul links capacityis about 2.1 times higher than the access links capac-ity. Based on these capacity numbers, The authorsinvestigated the feasibility of the proposed in-bandmmWave backhaul solution.

Furthermore, the authors provided the link capac-ity results for the best NLoS path on the BL andNLoS path for the AL (Table 1), where “DL/UL”

Figure 4.1: Monte Carlo simulation setup for evaluating wire-less backhaul feasibility and observations: a) Monte Carlo sim-ulation scenario for evaluating feasibility of in-band wirelessbackhaul; b) CDFs of the instantaneous capacities on the BLand ALs (uplink, UL, and downlink, DL); c) parameters usedfor the Monte Carlo simulations; d) average link capacities ob-tained using Monte Carlo simulations.

indicates the downlink-to-uplink ratio for resourceallocation in a time-division duplex (TDD) system.Based on their simulation, the authors observed thatusing only 25 percent of the AL resources for the BLis sufficient to support user data rates as high as 0.8Gb/s.

After this first step of investigation (i.e. the feasi-

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 8

Figure 4.2: . Feasible AL and BL rates assuming non-line-of-sight (NLoS) conditons on the AL and best NLoS conditionson the BL for various downlink to uplink ratios. Best NLoScondition can be assumed on the BL as there is ample time tochoose the best NLoS setting (which does not change very often)compared to the AL.

bility of in-band backhaul at mmWave frequencies),the authors discussed the deployment assumptionsand system design constraints applicable in a practi-cal system. Then, they outlined a BS-to-BS schedul-ing scheme for the BL that can be multiplexed withthe usual BS-to-MS scheduling for in-band backhauland access deployment scenario. Finally, the au-thors open the door for other avenues of interest (e.g.investigations into Spatial division multiple access(SDMA) and full-duplexing capabilities) for furtherspectral efficiency enhancements.

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 9

Review of “Small Cell In-Band Wireless Backhaulin Massive MIMO Systems: A Cooperation of

Next- Generation Techniques”IEEE Transactions on Wireless Communications, December 2015

Authors: B. Li, D. Zhu, and P. Liang

Massive multiple-input-multiple-output (MIMO)systems, dense small-cells (SCs), and full duplexare three candidate techniques for next-generationcommunication systems. The cooperation of next-generation techniques could offer more benefits.

In this work, in-band wireless backhaul usingmassive MIMO systems was studied. In addition,various duplex techniques for improving through-put over in-band backhaul links were investigated.This work mainly focuses on analyzing the averageachievable sum rate for backhaul transmission anddata transmission with the allocated in-band band-width. The authors discussed the potential through-put improvement introduced by SC in-band wirelessbackhaul in massive MIMO systems. After provid-ing an overview of massive MIMO system, threestrategies of dense small-cells (SCs), in-band wire-less backhaul in massive MIMO systems were intro-duced and compared.

The first one is Complete TDD (CTDD), whichfurther divides the communication between the BSand SCs and the data exchanges between SCs andtheir associated User Equipment (UEs) in the timedivision. The second strategy is based on zero-

division duplex (ZDD), which requires that SCsare capable to do self-interference cancellation thuscould transmit and receive signals in the same time-frequency resource. The third one is called ZDDwith interference rejection (ZDD-IR). ZDD-IR is ac-tually an enhanced version of ZDD, which has anadditional requirement that the BS can apply theIR procedure. Then the authors calculated the av-erage achievable sum rate values of downlink anduplink for the three strategies. In their work, un-correlated Rayleigh fading is applied as the channelmodel and perfect channel state information is as-sumed for simulations. To exploit the advantages ofmultiple antennas, the authors use the Non-Line-of-Sight (NLoS) models with shadowing at the carrierfrequency fc = 2 GHz. Based on the simulations,the authors attested that among the three strategies,CTDD is the simplest one and could achieve a decentthroughput gain for an in-band wireless backhaul inmassive MIMO systems.

However, there are various open questions whichstill need to be addressed, such as consideration ofthe interference from macro and the inter-SC in-terference. For interference in co-channel deploy-

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 10

ment, it is usually the macro cells that are interfer-ing with the small cells/backhauls due to the largetransmit power disparity between the macro andsmall cells. Coordinated architecture can be ex-plored through cloud computing for better interfer-ence management. To reduce the inter-SC interfer-ences, a coordinated cell switch off methods mightneed to be investigated. The authors also kept thedoors open for further investigation using more re-alistic assumptions such as realistic channel modelsand channel estimation errors.

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 11

IEEE ETI-BNC Online Panel 2019Networked-Flying Platforms: Paving the Way

Towards Global Wireless Connectivity

Call for Participation

Join us for IEEE ETI-BNC 4th Meeting: OnlinePanel: Networked-Flying Platforms: Paving the WayTowards Global Wireless Connectivity

Monday, 1 Jul, 2019 14:00 — 1 hour —(UTC+00:00) Dublin, Edinburgh, Lisbon, LondonMeeting number: 590 693 294

Agenda: Driven by an emerging use of NetworkedFlying Platforms (NFPs) such as unmanned aerialvehicles (UAVs) and unmanned balloons in futurenetwork applications and the challenges that the 5Gand beyond networks exhibit, the focus of this Paneldiscussions is to demonstrate the evolution of theNFPs as a novel architectural enabler for radio ac-cess network (RAN) and their integration with thefuture cellular access and backhaul/fronthaul net-works. NFPs are networked, flying and a potentialway to offer high data rate, high reliability and ultra-low latent access and backhaul/fronthaul to futurewireless networks. Specifically, this panel will pro-vide answers for the following:

• How NFPs can offer a reliable, high data rateand scalable solution to fronthaul the ultra-dense small cell deployment (NFPs deploymentarchitecture, potential high data rate technolo-gies, and NFP-small cell association)?

• How NFPs can enhance capacity and cover-age for users and access networks (NFP place-ment, resource allocation and network anduser/network centric approaches)?

• What are the economic, regulatory and indus-trial perspectives of deploying NPFs for cellu-lar access and backhaul networks (total cost ofoperation and some latest regulations)?

Panelists

• University of the West of Scotland, UK

• KAUST, SA

• FACEBOOK, USA

• University of Glasgow, UK

• Carleton University, Canada

Join WebexJoin by phone +1 210 606 9466 US Toll +1 866

282 7366 US Toll Free Access code: 590 693 294

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 12

Call for Papers: IEEE JSACDesign and Analysis of Communication Interfaces

for Industry 4.0

Publication DateFirst/Second Quarter 2020Manuscript Submission Deadline July 1, 2019

Call for Papers

The fourth industrial revolution also referred to as In-dustry 4.0 aims to integrate advanced manufacturingtechniques with the Internet-of-Things (IoT) to cre-ate an agile digital manufacturing ecosystem. Thekey idea is to provide a higher level of automationby combining technologies such as Industrial IoT(IIoT), cloud computing, machine learning (ML) andadvanced robotics to enable the creation of intercon-nected, responsive, intelligent and self-optimizingmanufacturing processes and systems. The increasedautomation can:

• Significantly enhance operational efficiencythrough real-time process analytics or even end-to-end process control.

• Significantly enhance overall productivity byrealizing zero-downtime through proactivemaintenance via the implementation of “digitaltwins”.

Implementation of either real-time process analyt-ics or digital twining is geared to generate a huge vol-

ume of heterogeneous data flows. Consequently, thedesign of communication interfaces to support inter-connectivity must be optimized to enable conver-gence between legacy operations technology (OT)and next-generation IIoT.

This special issue solicits original research papersfocused on Design and Analysis of:

• Ultra-reliable Low-Latency Connectivity Inter-faces for IIoT Networks

• Spectrum Management and Coexistence Issuesfor IIoT Networks

• Architecture and Protocols for IIoT Networks

• Novel ML methods for implementing Self-Xcapabilities in IIoT Networks

• Resource Allocation and Management for IIoTNetworks

• Security, Privacy and Trust issues in IIoT de-ployments

• Interoperability and Convergence Issues forlegacy OT and IIoT Networks

• Application and Deployment Specific Issues forIIoT Networks

Issue 3, April 2019

IEEE ComSoc ETI-BNC Blog 13

Submission Guidelines

All submissions have to be prepared according to theInformation for Authors as published in the Journalwebsite and must be submitted via EDAS.

Important Dates

Manuscript Due: 1 July 2019Acceptance Notification: 30 September 2019Final Manuscript Due: 15 November 2019Expected Publication of the Special Issue:First/Second Quarter 2020

Guest Editors

Syed A. R. ZaidiUniversity of Leeds, UK

Muhammad Zeeshan ShakirThe University of West of Scotland, UK

Antonio J. JaraUniversity of Applied Sciences Western Switzerland

Yunchuan SunBeijing Normal University, China

Rohit AilSamsung Technology Research, UK

Houbing SongEmbry-Riddle Aeronautical University, USA

Sid Chi-Kin ChauAustralian National University, Australia

Issue 3, April 2019