'The Future Inter-connected Network' and Timing, Frequency & Phase requirements

I had the pleasure of doing a keynote at PhaseReady 2015 in London today. My presentation is embedded below along with some comments, followed by tweets some of which I think are important to think about. Finally, I have embedded a video by EE and Light Reading which was quoted and maybe its important in the context of this event.

The Future Inter-connected Network from Zahid Ghadialy

My main focus during this presentation has been on how the networks have evolved from 3G days with the main focus (unconsciously) on speeds. While the networks are evolving, they are also getting more complex. The future ecosystem will consist of many Inter-connected (and in many cases inter-operable) networks that will work out the requirements in different situations and adapt to the necessary network(technology) accordingly.

An example of today's networks are like driving a manual car where we have to change gears depending on the traffic, speed required and fuel efficiency. Automatic cars are supposed to optimise this and achieve the best in all different cases. The future inter-connected networks should achieve the best based on the requirements in all different scenarios.

While it is easy to say this in theory, the practical networks will have many challenges to solve, including business and/or technical. The theme of the conference was timing, frequency and phase synchronisation. There are already challenges around them today, with the advanced LTE-A features. These challenges are only going to get bigger.

The following are the tweets from the day:

Finally, here is the link to video referred to in the last tweet. Its from last year but well worth listening.

'5G' talks from Johannesburg Summit 2015

The annual Johannesburg Summit took place May 10th-12th 2015. While it seems like there is a 5G related event every week, most of the events focus on different themes, use cases, applications and possibilities.

While there were some quite futuristic grand visions, there were a few technical presentations that would be a treat to the audience of this blog. I would especially recommend the presentations from Qualcomm and Samsung. Here is a video of all the presentations:


Some of the presentations from this summit, in PDF format are available here.

The path from 4.5G to 5G

In the WiFi Global Congress last week, I heard this interesting talk from an ex-colleague who now works with Huawei. While there were a few interesting things, the one I want to highlight is 4.5G. The readers of this blog will remember that I introduced 4.5G back in June last year and followed it with another post in October when everyone else started using that term and making it complicated.

According to this presentation, 3GPP is looking to create a new brand from Release-13 that will supersede LTE-Advanced (LTE-A). Some of you may remember that the vendor/operator community tried this in the past by introducing LTE-B, LTE-C, etc. for the upcoming releases but they were slapped down by 3GPP. Huawei is calling this Release-13 as 4.5G but it would be re-branded based on what 3GPP comes up with.

Another interesting point are the data rates achieved in the labs, probably more than others. 10.32Gbps in sub-6GHz in a 200MHz bandwidth and 115.20Gbps using a 9.6GHz bandwidth in above 6GHz spectrum. The complete presentation as follows:

Huawei: Paving the Way to 5G from Zahid Ghadialy

Another Huawei presentation that merits inclusion is the one from the last Cambridge Wireless Small Cells SIG event back in February by Egon Schulz. The presentation is embedded below but I want to highlight the different waveforms that being being looked at for 5G. In fact if someone has a list of the waveforms, please feel free to add it in comments

Research challenges in #5G #IEEE #Bangalore #5GTechnologyWorkshop pic.twitter.com/CQhwGfVb8T

— Amod Anandkumar (@amodjaiga) May 22, 2015

The above tweet from a recent IEEE event in Bangalore is another example of showing the research challenges in 5G, including the waveforms. The ones that I can obviously see from above is: FBMC, UFMC, GFDM, NOMA, SCMA, OFDM-opt, f-OFDM.

The presentation as follows:

Huawei: Forward 2020 -> 5G from Zahid Ghadialy

3GPP Release-13 work started in earnest

The 3GPP news from some months back listed the main RAN features that have been approved for Release-13 and the work has already started on them. The following are the main features (links contain .zip files):

• LTE in unlicensed spectrum (aka Licensed-Assisted Access) - RP-150055
• Carrier Aggregation enhancements - RP-142286
• LTE enhancements for Machine-Type Communications (MTC) - RP-141865
• Enhancements for D2D - RP-142311
• Study Item Elevation Beamforming / Full-Dimension MIMO - RP-141831
• Study Item Enhanced multi-user transmission techniques - RP-142315
• Study Item Indoor positioning - RP-141102
• Study Item Single-cell Point-to-Multipoint (SC-PTM) - RP-142205

Another 3GPP presentation from late last year showed the system features that were being planned for Rel-13 as shown above.

I have also posted a few items earlier relating to Release13, as follows:

• LTE Category-0 low power M2M devices
• Update on Public Safety and Mission Critical communications
• 3GPP Rel-12 and Future Security Work
• Elevation Beamforming / Full-Dimension MIMO
• LA-LTE and LAA
• LTE-Hetnet (LTE-H) a.k.a. LTE Wi-Fi Link Aggregation (LWA)

Ericsson has this week published a whitepaper on release 13, with a vision for 'Networked Society':

The vision of the Networked Society, where everything that benefits from being connected will be connected, places new requirements on connectivity. LTE is a key component in meeting these demands, and LTE release 13 is the next step in the LTE evolution.

Their whitepaper embedded below:

It should be pointed out that 5G work does not start until Release-15 as can be seen from my tweet

Nice picture of "5G Radio Interface development timeline" by @alainmouradUK pic.twitter.com/ANFfujJGS5
— Zahid Ghadialy (@zahidtg) April 4, 2015

xoxoxo Added Later (26/04/2015) xoxoxo
I came across this presentation from Keysight (Agilent) where Moray Rumney has provided information in much more detail.

5G and NFV

In my 5G: A 2020 vision presentation, I argued that some of the technologies that will be necessary for 5G is in fact independent of 5G. One such technology is NFV. Having said that, I also argue that the minimum prototype for 5G would require an NFV based implementation.

Tieto gave an interesting presentation in our last Small Cell SIG event explaining how the network will be implemented based on NFV. The presentation is embedded below:

5G: Building upon ongoing network disruption from Zahid Ghadialy

There is also an interesting paper that expands on this further, available from Slideshare here.

5G: A 2020 Vision

I had the pleasure of speaking at the CW (Cambridge Wireless) event ‘5G: A Practical Approach’. It was a very interesting event with great speakers. Over the next few weeks, I will hopefully add the presentations from some of the other speakers too.

In fact before the presentation (below), I had a few discussions over the twitter to validate if people agree with my assumptions. For those who use twitter, maybe you may want to have a look at some of these below:

5G is coming, maybe much earlier than you expect it to. There is a race to be first. Come... http://t.co/BQUR5p3bpk pic.twitter.com/z3cOD7Xv2O
— eXplanoTech (@eXplanoTech) January 30, 2015

@disruptivedean @ericsson Re 2% only cellular, I was discussing this the other day. Too many competing techs. pic.twitter.com/Z7s6wqxkBM
— Zahid Ghadialy (@zahidtg) January 26, 2015

Spectrum Bands Summary - Can anyone point me to a better picture? (Cc @open_spectrum @StevenJCrowley @elenaneira) pic.twitter.com/IkBhtQubSj
— Zahid Ghadialy (@zahidtg) January 19, 2015

Anyway, here is the presentation.

 

5G: A 2020 Vision from eXplanoTech

IEEE Globecom 2014 Keynote Video: 5G Wireless Goes Beyond Smartphones

Embedded below is a video from the keynote session by Dr. Wen Tong of Huawei. I do not have the latest presentation but an earlier one (6 months old) is also embedded below for reference. It will give you a good idea on the 5G research direction

5G Wireless Goes Beyond Smartphones from Zahid Ghadialy

You may also be interested in this other presentation from Huawei in IEEE Globecom 2014, 5G: From Research to Standardization (what, how, when)

5G Spectrum and challenges

I was looking at the proposed spectrum for 5G last week. Anyone who follows me on Twitter would have seen the tweets from last weekend already. I think there is more to discuss then just tweet them so here it is.

Metis has the most comprehensive list of all the bands identified from 6GHz, all the way to 86GHz. I am not exactly sure but the slide also identifies who/what is currently occupying these bands in different parts of the world.

The FCC in the USA has opened a Notice of Inquiry (NoI) for using the bands above 24GHz for mobile broadband. The frequency bands above have a potential as there is a big contiguous chunk of spectrum available in each band.

Finally, the slides from ETRI, South Korea show that they want to have 500MHz bandwidth in frequencies above 6GHz.

As I am sure we all know, the higher the frequency, the lower the cell size and penetration indoors. The advantage on the other hand is smaller cell sizes, leading to higher data rates. The antennas also become smaller at higher frequencies thereby making it easier to have higher order MIMO (and massive MIMO). The only way to reliably be able to do mobile broadband is to use beamforming. The tricky part with that is the beam has to track the mobile user which may be an issue at higher speeds.

The ITU working party 5D, recently released a draft report on 'The technical feasibility of IMT in the bands above 6 GHz'. The document is embedded below.

ITU Working Party 5D: The technical feasibility of IMT in the bands above 6 GHz from Zahid Ghadialy

xoxoxo Added Later (13/12/2014) xoxoxo
Here are some links on the related topic:

• IEEE ComSoc: 5G Wireless Demos Use High Frequencies
• HUAWEI, TELE2 disagree on role of spectrum for 5G

xoxoxo Added Later (18/12/2014) xoxoxo
Moray Rumney from Keysight (Agilent) gave a presentation on this topic in the Cambridge Wireless Mobile Broadband SIG event yesterday, his presentation is embedded below.

New Spectrum Usage Paradigms for 5G

Sometime back I wrote a post that talked about Dynamic Spectrum Access (DSA) techniques for Small Cells and WiFi to work together in a fair way. The Small Cells would be using the ISM bands and Wi-Fi AP's would also be contending for the same spectrum. For those who may not know, this is commonly referred to as LTE-U but the correct term that is being used in standards is LA-LTE, see here for details.

IEEE Comsoc has just published a whitepaper that details how the spectrum should be handled in 5G to make sure of efficient utilisation. The whitepaper covers the following:

Chapter 2 – Introduction, the traditional approach of repurposing spectrum and allocating it to Cellular Wireless systems is reaching its limits, at least below the 6GHz threshold. For this reason, novel approaches are required which are detailed in the sequel of this White Paper.

Chapter 3 - Spectrum Scarcity - an Alternate View provides a generic view on the spectrum scarcity issue and discusses key technologies which may help to alleviate the problem, including Dynamic Spectrum Management, Cognitive Radios, Cognitive Networks, Relaying, etc. 

Chapter 4 – mmWave Communications in 5G addresses a first key solution. While spectrum opportunities are running out at below 6 GHz, an abundance of spectrum is available in mmWave bands and the related technology is becoming mature. This chapter addresses in particular the heterogeneous approach in which legacy wireless systems are operated jointly with mmWave systems which allows to combine the advantages of both technologies. 

Chapter 5 – Dynamic Spectrum Access and Cognitive Radio: A Current Snapshot gives a detailed overview on state-of-the-art dynamic spectrum sharing technology and related standards activities. The approach is indeed complementary to the upper mmWave approach, the idea focuses on identifying unused spectrum in time, space and frequency. This technology is expected to substantially improve the usage efficiency of spectrum, in particular below the 6GHz range. 

Chapter 6 – Licensed Shared Access (LSA) enables coordinated sharing of spectrum for a given time period, a given geographic area and a given spectrum band under a license agreement. In contract to sporadic usage of spectrum on a secondary basis, the LSA approach will guarantee Quality-of-Service levels to both Incumbents and Spectrum Licensees. Also, a clear business model is available through a straightforward license transfer from relevant incumbents to licensees operating a Cellular Wireless network in the concerned frequency bands. 

Chapter 7 – Radio Environment Map details a technology which allows to gather the relevant (radio) context information which feed related decision making engines in the Network Infrastructure and/or Mobile Equipment. Indeed, tools for acquiring context information is critical for next generation Wireless Communication systems, since they are expected to be highly versatile and to constantly adapt. 

Chapter 8 – D2DWRAN: A 5G Network Proposal based on IEEE 802.22 and TVWS discusses the efficient exploitation of TV White Space spectrum bands building on the available IEEE 802.22 standard. TV White Spaces are indeed located in highly appealing spectrum bands below 1 GHz with propagation characteristics that are perfectly suited to the need of Wireless Communication systems. 

Chapter 9 – Conclusion presents some final thoughts. 

The paper is embedded as follows:

Novel Spectrum Usage Paradigms for 5G from Zahid Ghadialy

What is (pre-5G) 4.5G?

Before we look at what 4.5G is, lets look at what is not 4.5G. First and foremost, Carrier Aggregation is not 4.5G. Its the foundation for real 4G. I keep on showing this picture on Twitter

I am sure some people much be really bored by this picture of mine that I keep showing. LTE, rightly referred to as 3.9G or pre-4G by the South Korean and Japanese operators was the foundation of 'Real' 4G, a.k.a. LTE-Advanced. So who has been referring to LTE-A as 4.5G (and even 5G). Here you go:

Got 4G? Wake up, grandad. We're doing 4.5G LTE-A in London - EE chief: And get a load of our gleaming voice system! … http://t.co/78HSHlyPuA
— The Register (@TheRegister) March 5, 2014

Voda UK PR says: "The new technology, called Carrier Aggregation but also referred to as LTE Advanced or 4.5G" 4.5G?
— Keith Dyer (@keithdyer) October 15, 2014

5G wireless technology LTE-Advanced is now running in the Philippines' largest and strongest network. | http://t.co/g8u3lJ8sLV #Smart5G
— Smart Communications (@SMARTCares) August 14, 2014

So lets look at what 4.5G is.

Back in June, we published a whitepaper where we referred to 4.5G as LTE and WiFi working together. When we refer to LTE, it refers to LTE-A as well. The standards in Release-12 allow simultaneous use of LTE(-A) and WiFi with selected streams on WiFi and others on cellular.

Some people dont realise how much spectrum is available as part of 5GHz, hopefully the above picture will give an idea. This is exactly what has tempted the cellular community to come up with LTE-U (a.k.a LA-LTE, LAA)

In a recent event in London called 5G Huddle, Alcatel-Lucent presented their views on what 4.5G would mean. If you look at the slide above, it is quite a detailed view of what this intermediate step before 5G would be. Some tweets related to this discussion from 5G Huddle as follows:

Good points: 4.5G as necessary step: CA, VoLTE & WebRTC, CoMP & coordination, NFV & cloud. But that can do everything we need #5GHuddle
— Real Wireless (@real_wireless) September 23, 2014

So 5G will be evolution of 4.5G using DC & CA - but much better signalling, more energy efficient as new air interface for IoT
— Real Wireless (@real_wireless) September 23, 2014

Finally, in a recent GSMA event, Huawei used the term 4.5G to set out their vision and also propose a time-frame as follows:

While in Alcatel-Lucent slide, I could visualise 4.5G as our vision of LTE(-A) + WiFi + some more stuff, I am finding it difficult to visualise all the changes being proposed by Huawei. How are we going to see the peak rate of 10Gbps for example?

I have to mention that I have had companies that have told me that their vision of 5G is M2M and D2D so Huawei is is not very far from reality here.

We should keep in mind that this 4G, 4.5G and 5G are the terms we use to make the end users aware of what new cellular technology could do for them. Most of these people understand simple terms like speeds and latency. We may want to be careful what we tell them as we do not want to make things confusing, complicated and make false promises and not deliver on them.

xoxoxo Added on 2nd January 2015 oxoxox

Chinese vendor ZTE has said it plans to launch a ‘pre-5G’ testing base station in 2015, commercial use of which will be possible in 2016, following tests and adjustment. Here is what they think pre-5G means:

'Real' Full Duplex (or No Division Duplex - NDD?)

We all know about the two type of transmission schemes which are FDD and TDD. Normally, this FDD and TDD schemes are known as full duplex schemes. Some people will argue that TDD is actually half-duplex but what TDD does is that it emulates a full duplex communication over a half duplex communication link. There is also a half-duplex FDD, which is a very interesting technology and defined for LTE, but not used. See here for details.

One of the technologies being proposed for 5G is referred to as Full Duplex. Here, the transmitter and the receiver both transmit and receive at the same frequency. Due to some very clever signal processing, the interference can be cancelled out. An interesting presentation from Kumu networks is embedded below:

Full Duplex Radios in 5G from Zahid Ghadialy

The biggest challenge is self-interference cancellation because the transmitter and receiver are using the same spectrum and will cause interference to each other. There have been major advances in the self-interference cancellation techniques which could be seen in the Interdigital presentation embedded below:

Potential of Full Duplex for Future Wireless Systems from Zahid Ghadialy

NFV and 5G compatibility issues

There was an interesting discussion on Twitter that has been storified by Keith Dyer. Lets start by having a quick look at the C-RAN architecture that features in the discussion.

There are couple of excellent C-RAN presentations for anyone interested. This one by EE (with 9K+ views) and this from Orange (with 19K+ views).

Anyway, here is the story:

For anyone interested in exploring the discussion further, The Mobile Network has a more detailed comments here.

There are also an interesting article worth reading:

• Clouding the Edge for LTE-A and Beyond
• 5G Will Give Operators Massive Headaches – Bell Labs

Taking 5G from vision to reality

This presentation by Moray Rumney of Agilent (Keysight) in Cambridge Wireless, Future of Wireless International conference takes a different angle at what the targets for different technologies have been and based on that what should be the targets for 5G. In fact he has an opinion on M2M and Public safety as well and tries to combine it with 5G. Unfortunately I wasnt at this presentation but from having heard Moray speak in past, I am sure it was a thought provoking presentation.

Taking 5G from vision to reality from Zahid Ghadialy

All presentations from the Future of Wireless International Conference (FWIC) are available here.

Cell capacity and Opportunistic Use of Unlicensed and Shared Spectrum

One very interesting presentation from the LTE World Summit was about Improving the cell capacity by using unlicensed and shared spectrum opportunistically. Kamran Etemad is a senior advisor to FCC & UCMP and even though he was presenting this in his personal capacity, it reflected some interesting views that are quite prevalent in the USA.

If you don't know about Dynamic Spectrum Access Schemes, I wrote a post on the Small Cells blog here. The slide above is quite interesting as it shows the possibility of a 'Generalized' Carrier Aggregation in 3GPP Release-13. Personally, we believe that LTE + WiFi working together will be far more successful than LTE + LTE-U (unlicensed). As the blog readers would be aware, we have been pushing our vision of LTE + Wi-Fi working together; which we are calling as 4.5G. In case if you have not seen, our whitepaper is here.

The presentation is embedded below for reference:

Improving Cell Capacity of 5G Systems Through Opportunistic Use of Unlicensed and Shared Spectrum from Zahid Ghadialy

5G and the ‘Millimeter-Wave' Radios

There were quite a few interesting talks in the Cambridge Wireless Radio Technology SIG event last week. The ones that caught my attention and I want to highlight here are as follows.

The mobile operator EE and 5GIC centre explained the challenges faced during the Practical deployments. Of particular interest was the considerations during deployments. The outdoor environments can change in no time with things like foliage, signage or even during certain festivals. This can impact the radio path and may knock out certain small cells or backhaul. The presentation is available to view and download here.

Another interesting presentation was from Bluwireless on the 60GHz for backhaul. The slide that was really shocking was the impact of regulation in the US and the EU. This regulation difference means that a backhaul link could be expensive and impractical in certain scenarios in the EU while similar deployments in the US would be considerably cheaper. This presentation is available here.

Finally, the presentation from Samsung highlighted their vision and showed the test results of their mmWave prototype. The presentation is embedded below and is available here.

Vision and Key Features for 5th Generation (5G) Cellular - Samsung from Zahid Ghadialy

Finally, our 5G presentation summarising our opinion and what 5G may contain is available here. Dont forget to see the interesting discussion in the comments area.

ETSI Summit on Future Mobile and Standards for 5G

Edited from the original in 3GPP News:

The ETSI Future Mobile Summit has heard how the mobile internet will evolve over the next ten to fifteen years, and how 3GPP systems will ensure future stability as the network copes with an explosive growth in complexity and usage.

With 3GPP providing the evolutionary framework for mobility, via its Releases of new functionality and features, the more radical thinking, at the Summit, came in the form of Research projects and some future focused industry initiatives, such as the WWRF, the METIS Project and the DVB Project.

In his keynote address, Mario Campolargo - of the European Commission - introduced a new initiative on research & innovation that will provide momentum to funded work on research. The 5G Public Private Partnership is being launched as a blueprint for the deployment of 5G, in the years after 2020. 

In summing up the Summit’s main themes, the ETSI CTO, Adrian Scrase identified some certainties; “...traffic will continue to increase, connected devices will increase dramatically over time, new device types will significantly contribute to that increase (e.g., probes, sensors, meters, machines etc) and new sectors will bring new priorities (e.g, critical infrastructures).”

On the concept of 5G, Mr. Scrase reported that ultra-reliable 5G networks should, among other things, enable the tactile internet, the perception of infinite capacity and bring in augmented reality.

ETSI Future Mobile Summit: Key Messages from Zahid Ghadialy

Download the presentations:

5G, the way forward! Mario Campolargo, Director, Net Futures, DG Connect, European Commission	A new initiative 5GPPP, to accelerate and structure research & innovation."...Industry to co-create the "vision" and build global convergence by end 2015.
Who needs 5G? Hans D. Schotten, University of Kaiserslautern	Long Term Evolution of LTE (linear evolution) or Something new (5G)?
Why 5G? Rahim Tafazolli, Director of CCSR and 5GIC, The university of Surrey	Perceived infinite capacity, a new communication paradigm for 5G and Beyond
The 5G mobile and wireless communications system  Afif Osseiran, Project Coordinator of METIS	Explanation of 5G scenarios (selected) and examples of 5G technology components
Next generation wireless for a cognitive & energy-efficient future Nigel Jefferies, Wireless World Research Forum Chairman	"New technology challenges: huge number of nodes, latency , energy efficiency, backhaul and over the air signaling design...May require a whole new approach to: physical layer, air interface and spectrum usage, resources management & optimization..."
3GPP Radio Access Network : Rel-12 and beyond Dino Flore, 3GPP RAN Chairman	3GPP RAN has started a new innovation cycle which will be shaping next generation cellular systems
Spectrum for 5G, a big deal? Jens Zander, KTH, Royal Institute of Technology	A World Divided - The coverage world versus the capacity world
Opportunities for TV services over future mobile networks Nick Wells, Chairman Technical Module, DVB	Can broadcasters and mobile industry cooperate to define a new worldwide standard that will benefit both broadcasters and mobile industry?
3GPP core network & services evolution Atle Monrad, 3GPP CT Chairman	Architecture evolution, More new nodes, CS-domain removal?, new ways of design of networks?
The impact of NFV on future mobile Uwe Janssen, Deutsche Telekom, lead delegate to Network Functions Virtualisation ISG	The challenge for Operators, Suppliers and Standards Bodies
The tactile internet - Driving 5G Gerhard Fettweis, Technical University of Dresden	3D Chip-Stacks & High-Rate Inter-Chip Communications, Monitoring / Sensing, Tactile internet - Latency Goals
Summit conclusions Adrian Scrase, ETSI CTO, Head of 3GPP MCC	Includes the 'Standardization Challenges' raised by the Summit.