Showing posts with label Interdigital. Show all posts
Showing posts with label Interdigital. Show all posts

Tuesday, October 15, 2019

Summary of #CWTEC 2019 Conference: 5G, Satellites & Magic MIMO

I was involved in helping organise yet another CW TEC conference this year. The topic was quite interesting and we had some brilliant speakers. Some of the excellent presentations were shared too, links below. Here is a very quick summary of the event, linking also to couple of excellent summaries below.

The topic was a bit unusual and it rhymed very well with the attendees which were from many different backgrounds, from 5G, communications, satellites, electronics, T&M companies, etc. Here is the opening video that will show you the motivations behind this



The day started with a breakfast briefing from Cambridge Consultants that looked at how Massive MIMO is the key to unlocking 5G User Experiences. Presentations available here.


Session 1 was titled "What has Massive MIMO ever done for us?". The narrative for the session was as follows:
Clearly the desire for more and more capacity in cellular networks has driven the industry to find more and more novel techniques. The work done over the years and boosted by Tom Marzetta’s article titled “Noncooperative Cellular Wireless with Unlimited Numbers of Base Station Antennas” has set high expectations for this emergent technology, so much so the term Magic MIMO has been coined. However, how significant is it into today’s early 5G rollout and what can we expect over the coming years? Are there still further enhancements we should expect to see?

There were 3 talks as follows:
  • Sync Architectures for 5G NR by Chris Farrow, Technical Manager, Chronos Technology (slides)
  • Three UK’s RAN transformation: Spectrum, RAN architecture strategy, Why? by Dr Erol Hepsaydir, Head of RAN and Devices Strategy and Architecture, Three UK (slides)
  • Active antenna systems in RAN: performance, challenges and evolution by Anvar Tukmanov, Wireless Research Manager, BT (slides)


Session 2 looked at "Non-Terrestrial & Hybrid Networks". The narrative for the session was as follows:
There are different initiatives underway to make satellite and other non-terrestrial networks as part of 5G. In addition, many different mobile operators have demonstrated compelling use-cases with drones, balloons and other aerostats. Other innovative approaches like European Aviation Network uses a hybrid-network using terrestrial network supported by a satellite connection as a backhaul for in-flight Wi-Fi. In addition to latency, what other challenges are stopping mass adoption of Non-terrestrial and Hybrid networks? What about advanced features like slicing, etc.?

There were 3 talks as follows:

  • Opportunities for blending terrestrial and satellite technologies by Dr Jaime Reed, Director, Consulting, Space, Defence and Intelligence, CGI (slides)
  • Non-terrestrial Networks: Standardization in 5G NR by Dr Yinan Qi, Senior 5G Researcher, Samsung R&D Institute UK (slides)
  • Satellites and 5G: A satellite operator’s perspective by Simon Watts, Principal Consultant, Avanti Communications (slides)


Session 3 looked at "5G: A Catalyst for Network Transformation". The narrative was as follows:
5G has set high expectations in the user as well as operator community. While eMBB can be supported with an upgrade of existing 4G infrastructure, URLLC and mMTC may require massive change in the network architecture. Operators have already started the transformation process with backhaul upgrades, new data centers, distributed core and cloud rollouts, etc. How are networks evolving to accommodate these deep changes? What other changes will be required in the network to support the growth until the next new generation arrives?
This session featured 3 talks as well
  • An Introduction to Open RAN Concept by Zahid Ghadialy, Senior Director, Strategic Marketing, Parallel Wireless UK & EMEA (slides)
  • Powering the successful deployment of 5G infrastructure by David George, Vice President of EMEA and APAC, Sitetracker (slides)
  • The 5G transformation: no sweet without sweat by Antonella Faniuolo, Head of Network Strategy, Planning, Digital & Optimisation, Vodafone (slides)


The final session topic was "Getting ready for Beyond-5G Era". The narrative was as follows:
Many technologies like Full duplex, etc. that were originally intended to be part of 5G were not able to make it into the standards. Along with these, what other revolutionary changes are needed to make Beyond-5G technologies not only fulfil the vision, ambition and use-cases that were originally envisaged for 5G but to take it a step further and make it a game changer.
This session featured 3 talks as well, as follows:
  • Thinking Beyond 5G: Projects and Initiatives by Alan Carlton, Vice President, InterDigital Europe (slides not available)
  • 5G Evolution: Progressive enhancement and new features for new markets by Matthew Baker, Head of Radio Physical Layer and Coexistence Standardization, Nokia (slides)
  • Why 6G’s design goals need far more than just radio & core innovation by Dean Bubley, Analyst & Futurist, Disruptive Analysis (slides not available)
And my personal highlight was that I launched World's first coloured 5G tie


Hopefully you found the presentations shared as useful. Please also read the summaries of CWTEC provided below.


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Saturday, March 2, 2019

Beyond-5G and 6G at #MWC19


MWC is huge and there is absolutely no way that I even managed to cover 1% of the floor, even though I spend half a day, every day looking at the demos and talking to companies. I came across just a couple of companies looking at post 5G research. One was Mehdi Bennis, from University of Oulu and a good friend of this blog and the other one was Interdigital, which has featured heavily on 3G4G blogs too.

From the standards point of view, I am only aware of ITU 'Network 2030' (FG NET-2030) that is looking at how future network architectures, requirements, use cases, and capabilities of the networks will change by 2030 and beyond. I blogged about it here.

It's too early to call anything as 6G because we don't even realise the ways in which 5G will change the world and the limitations that will feed into the requirements of IMT-2030 (just guessing the probable name).

So here is the first video from Mehdi Bennis.






I also caught up with Interdigital and I got a very detailed video on their vision of what comes beyond 5G



Would love to know what else did I miss on 6G and Beyond-5G at MWC 2019.

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Friday, September 14, 2018

End-to-end Network Slicing in 5G

I recently realised that I have never written a post just on Network slicing. So here is one on the topic. So the first question asked is, why do we even need Network Slicing? Alan Carlton from Interdigital wrote a good article on this topic. Below is what I think is interesting:

Network slicing is a specific form of virtualization that allows multiple logical networks to run on top of a shared physical network infrastructure. The key benefit of the network slicing concept is that it provides an end-to-end virtual network encompassing not just networking but compute and storage functions too. The objective is to allow a physical mobile network operator to partition its network resources to allow for very different users, so-called tenants, to multiplex over a single physical infrastructure. The most commonly cited example in 5G discussions is sharing of a given physical network to simultaneously run Internet of Things (IoT), Mobile Broadband (MBB), and very low-latency (e.g. vehicular communications) applications. These applications obviously have very different transmission characteristics. For example, IoT will typically have a very large number of devices, but each device may have very low throughput. MBB has nearly the opposite properties since it will have a much smaller number of devices, but each one will be transmitting or receiving very high bandwidth content. The intent of network slicing is to be able to partition the physical network at an end-to-end level to allow optimum grouping of traffic, isolation from other tenants, and configuring of resources at a macro level.

Source: ITU presentation, see below

The key differentiator of the network slicing approach is that it provides a holistic end-to-end virtual network for a given tenant. No existing QoS-based solution can offer anything like this. For example, DiffServ, which is the most widely deployed QoS solution, can discriminate VoIP traffic from other types of traffic such as HD video and web browsing. However, DiffServ cannot discriminate and differentially treat the same type of traffic (e.g. VoIP traffic) coming from different tenants.

 Also, DiffServ does not have the ability to perform traffic isolation at all. For example, IoT traffic from a health monitoring network (e.g. connecting hospitals and outpatients) typically have strict privacy and security requirements including where the data can be stored and who can access it. This cannot be accomplished by DiffServ as it does not have any features dealing with the compute and storage aspects of the network. All these identified shortfalls of DiffServ will be handled by the features being developed for network slicing.

I came across this presentation by Peter Ashwood-Smith from Huawei Technologies who presented '5G End to-end network slicing Demo' at ITU-T Focus Group IMT-2020 Workshop and Demo Day on 7 December 2016. Its a great presentation, I wish a video of this was available as well. Anyway, the presentation is embedded below and the PPT can be downloaded from here.



The European Telecommunications Standards Institute (ETSI) has established a new Industry Specification Group (ISG) on Zero touch network and Service Management (ZSM) that is working to produce a set of technical specifications on fully automated network and service management with, ideally, zero human intervention. ZSM is targeted for 5G, particularly in network slice deployment. NTT Technical review article on this is available here.

Finally, here is a presentation by Sridhar Bhaskaran of Cellular Insights blog on this topic. Unfortunately, not available for download.


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Sunday, September 3, 2017

5G Core Network, System Architecture & Registration Procedure

The 5G System architecture (based on 3GPP TS 23.501: System Architecture for the 5G System; Stage 2) consists of the following network functions (NF). The functional description of these network functions is specified in clause 6.
- Authentication Server Function (AUSF)
- Core Access and Mobility Management Function (AMF)
- Data network (DN), e.g. operator services, Internet access or 3rd party services
- Structured Data Storage network function (SDSF)
- Unstructured Data Storage network function (UDSF)
- Network Exposure Function (NEF)
- NF Repository Function (NRF)
- Network Slice Selection Function (NSSF)
- Policy Control function (PCF)
- Session Management Function (SMF)
- Unified Data Management (UDM)
- Unified Data Repository (UDR)
- User plane Function (UPF)
- Application Function (AF)
- User Equipment (UE)
- (Radio) Access Network ((R)AN)

As you can see, this is slightly more complex than the 2G/3G/4G Core Network Architecture.

Alan Carlton, Vice President, InterDigital and Head of InterDigital International Labs Organization spanning Europe and Asia provided a concise summary of the changes in 5G core network in ComputerWorld:

Session management is all about the establishment, maintenance and tear down of data connections. In 2G and 3G this manifested as the standalone General Packet Radio Service (GPRS). 4G introduced a fully integrated data only system optimized for mobile broadband inside which basic telephony is supported as just one profile.

 Mobility management as the name suggests deals with everything that needs doing to support the movement of users in a mobile network. This encompasses such functions as system registration, location tracking and handover. The principles of these functions have changed relatively little through the generations beyond optimizations to reduce the heavy signaling load they impose on the system.

 The 4G core network’s main function today is to deliver an efficient data pipe. The existence of the service management function as a dedicated entity has been largely surrendered to the “applications” new world order. Session management and mobility management are now the two main functions that provide the raison d’etre for the core network.

 Session management in 4G is all about enabling data connectivity and opening up a tunnel to the world of applications in the internet as quickly as possible. This is enabled by two core network functions, the Serving Gateway (SGW) and Packet Data Gateway (PGW). Mobility management ensures that these data sessions can be maintained as the user moves about the network. Mobility management functions are centralized within a network node referred to as Mobility Management Entity (MME). Services, including voice, are provided as an “app” running on top of this 4G data pipe. The keyword in this mix, however, is “function”. It is useful to highlight that the distinctive nature of the session and mobility management functions enables modularization of these software functions in a manner that they can be easily deployed on any Commercial-Off-The-Shelf (COTS) hardware.

 The biggest change in 5G is perhaps that services will actually be making a bit of a return...the plan is now to deliver the whole Network as a Service. The approach to this being taken in 3GPP is to re-architect the whole core based on a service-oriented architecture approach. This entails breaking everything down into even more detailed functions and sub-functions. The MME is gone but not forgotten. Its former functionality has been redistributed into precise families of mobility and session management network functions. As such, registration, reachability, mobility management and connection management are all now new services offered by a new general network function dubbed Access and Mobility Management Function (AMF). Session establishment and session management, also formerly part of the MME, will now be new services offered by a new network function called the Session Management Function (SMF). Furthermore, packet routing and forwarding functions, currently performed by the SGW and PGW in 4G, will now be realized as services rendered through a new network function called the User Plane Function (UPF).

 The whole point of this new architectural approach is to enable a flexible Network as a Service solution. By standardizing a modularized set of services, this enables deployment on the fly in centralized, distributed or mixed configurations to enable target network configurations for different users. This very act of dynamically chaining together different services is what lies at the very heart of creating the magical network slices that will be so important in 5G to satisfy the diverse user demands expected. The bottom line in all this is that the emphasis is now entirely on software. The physical boxes where these software services are instantiated could be in the cloud or on any targeted COTS hardware in the system. It is this intangibility of physicality that is behind the notion that the core network might disappear in 5G.


3GPP TS 23.502: Procedures for the 5G System; Stage 2, provides examples of signalling for different scenarios. The MSC above shows the example of registration procedure. If you want a quick refresher of LTE registration procedure, see here.

I dont plan to expand on this procedure here. Checkout section "4.2.2 Registration Management procedures" in 23.502 for details. There are still a lot of FFS (For further studies 😉) in the specs that will get updated in the coming months.


Further Reading:

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Saturday, April 15, 2017

Self-backhauling: Integrated access and backhaul links for 5G


One of the items that was proposed during the 3GPP RAN Plenary #75 held in Dubrovnik, Croatia, was Study on Integrated Access and Backhaul for NR (NR = New Radio). RP-17148 provides more details as follows:

One of the potential technologies targeted to enable future cellular network deployment scenarios and applications is the support for wireless backhaul and relay links enabling flexible and very dense deployment of NR cells without the need for densifying the transport network proportionately. 

 Due to the expected larger bandwidth available for NR compared to LTE (e.g. mmWave spectrum) along with the native deployment of massive MIMO or multi-beam systems in NR creates an opportunity to develop and deploy integrated access and backhaul links. This may allow easier deployment of a dense network of self-backhauled NR cells in a more integrated manner by building upon many of the control and data channels/procedures defined for providing access to UEs. An example illustration of a network with such integrated access and backhaul links is shown in Figure 1, where relay nodes (rTRPs) can multiplex access and backhaul links in time, frequency, or space (e.g. beam-based operation).

 The operation of the different links may be on the same or different frequencies (also termed ‘in-band’ and ‘out-band’ relays). While efficient support of out-band relays is important for some NR deployment scenarios, it is critically important to understand the requirements of in-band operation which imply tighter interworking with the access links operating on the same frequency to accommodate duplex constraints and avoid/mitigate interference. 

 In addition, operating NR systems in mmWave spectrum presents some unique challenges including experiencing severe short-term blocking that cannot be readily mitigated by present RRC-based handover mechanisms due to the larger time-scales required for completion of the procedures compared to short-term blocking. Overcoming short-term blocking in mmWave systems may require fast L2-based switching between rTRPs, much like dynamic point selection, or modified L3-based solutions. The above described need to mitigate short-term blocking for NR operation in mmWave spectrum along with the desire for easier deployment of self-backhauled NR cells creates a need for the development of an integrated framework that allows fast switching of access and backhaul links. Over-the-air (OTA) coordination between rTRPs can also be considered to mitigate interference and support end-to-end route selection and optimization.

 The benefits of integrated access and backhaul (IAB) are crucial during network rollout and the initial network growth phase. To leverage these benefits, IAB needs to be available when NR rollout occurs. Consequently, postponing IAB-related work to a later stage may have adverse impact on the timely deployment of NR access.


There is also an interesting presentation on this topic from Interdigital on the 5G Crosshaul group here. I found the following points worth noting:

  • This will create a new type of interference (access-backhaul interference) to mitigate and will require sophisticated (complex) scheduling of the channel resources (across two domains, access and backhaul).
  • One of the main drivers is Small cells densification calling for cost-effective and low latency backhauling
  • The goal would be to maximize efficiency through joint optimization/integration of access and backhaul resources
  • The existing approach of Fronthaul using CPRI will not scale for 5G, self-backhaul may be an alternative in the shape of wireless fronthaul

Let me know what you think.

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Saturday, October 29, 2016

M2M vs IoT

This post is for mainly for my engineering colleagues. Over the years I have had many discussions to explain the difference between Machine-to-Machine (M2M) or Machine Type Communication (MTC) as 3GPP refers to them and the Internet of Things (IoT). Even after explaining the differences, I am often told that this is not correct. Hence I am putting this out here. Please feel free to express your views in the comments section.


Lets take an example of an office with 3 floors. Lets assume that each floor has a coffee machine like the one in this picture or something similar. Lets assume different scenarios:

Scenario 1: No connectivity
In this case a facilities person has to manually go to each of the floor and check if there are enough coffee beans, chocolate powder, milk powder, etc. He/She may have to do this say 3-4 times a day.

Scenario 2: Basic connectivity (M2M)
Lets say the coffee machine has basic sensors so it can send some kind of notification (on your phone or email or message, etc.) whenever the coffee beans, chocolate powder, milk powder, etc., falls below a certain level. In some cases you may also be able to check the levels using some kind of a app on your phone or computer. This is an example of M2M

Scenario 3: Advanced connectivity (IoT)
Lets say that the coffee machine is connected to the office system and database. It knows which employees come when and what is their coffee/drinks consumption pattern. This way the machine can optimize when it needs to be topped up. If there is a large meeting/event going on, the coffee machine can even check before the breaks and indicate in advance that it needs topping up with beans/chocolate/milk/etc.

Scenario 4: Intelligent Devices (Advanced IoT)
If we take the coffee machine from scenario 3 and add intelligence to it, it can even know about the inventory. How much of coffee beans, chocolate powder, milk powder, etc is in stock and when would they need ordering again. It can have an employee UI (User Interface) that can be used by employees to give feedback on which coffee beans are more/less popular or what drinks are popular. This info can be used by the machines to order the supplies, taking into account the price, availability, etc.

In many cases, API's would be available for people to build services on top of the basic available services to make life easier. Someone for example can build a service that if a cup is already at the dispenser and has been there for at least 2 minutes (so you know its not being used by someone else) then the person can choose/order their favourite drink from their seat so he/she doesn't have to wait for 30 seconds at the machine.

If you think about this further you will notice that in this scenario the only requirement for the human is to clean the coffee machine, top it up, etc. In future these can be automated with robots carrying out these kinds of jobs. There would be no need for humans to do these menial tasks.


I really like this slide from InterDigital as it captures the difference between M2M and IoT very well, especially in the light of the discussion above.

With the current M2M, we have:

  • Connectivity: connection for machines;
  • Content: massive raw data from things;

IoT is Communication to/from things which offer new services via cloud / context / collaboration / cognition technologies.

With evolution to IoT, we have:
  • Cloud: cloud service and XaaS (Everything as a Service) for IoT;
  • Context: context-aware design;
  • Collaboration: collaborative services;
  • Cognition: semantics and autonomous system adjustment
Let me know if you agree. 
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Sunday, September 18, 2016

5G Fronthaul: Crosshaul & XHaul

I have written about Fronthaul as part of C-RAN in this blog as well as in the Small Cells blog. I am also critical of the C-RAN concept now that the Baseband Units (BBU) have become small enough to go on the cell cite. I have expressed this view openly as can be seen in my tweet below.



While I am critical of the C-RAN approach, there are many vendors and engineers & architects within these vendors who are for or against this technology. I am going to leave the benefits and drawbacks of C-RAN in light of new developments (think Moore's law) for some other day.

The above picture from my earlier post explains the concept of Fronthaul and Backhaul for anyone who may not be aware. As data speeds keep on increasing with 4G, 4.5G, 4.9G, 5G, etc. it makes much more sense to use Fiber for Fronthaul. Dark fiber would be a far better choice than a lit one.

One thing that concerned me was what happens in case of MIMO or massive MIMO in 5G. Would we need multiple Fronthaul/Fibre or just a single one would do. After having some discussions with industry colleagues, looks like a single fiber is enough.

This picture above from an NTT presentation illustrates how WDM (Wavelength Division Multiplexing) can be used to send different light wavelengths over a single fiber thereby avoiding the need to have multiple of these fibers in the fronthaul.


There are 2 different projects ongoing to define 5G Fronthaul & Backhaul.

The first of these is 5G Crosshaul. Their website says:

The 5G-Crosshaul project aims at developing a 5G integrated backhaul and fronthaul transport network enabling a flexible and software-defined reconfiguration of all networking elements in a multi-tenant and service-oriented unified management environment. The 5G-Crosshaul transport network envisioned will consist of high-capacity switches and heterogeneous transmission links (e.g., fibre or wireless optics, high-capacity copper, mmWave) interconnecting Remote Radio Heads, 5GPoAs (e.g., macro and small cells), cloud-processing units (mini data centres), and points-of-presence of the core networks of one or multiple service providers. This transport network will flexibly interconnect distributed 5G radio access and core network functions, hosted on in-network cloud nodes, through the implementation of: (i) a control infrastructure using a unified, abstract network model for control plane integration (Crosshaul Control Infrastructure, XCI); (ii) a unified data plane encompassing innovative high-capacity transmission technologies and novel deterministic-latency switch architectures (Crosshaul Packet Forwarding Element, XFE).

The second is 5G XHaul. Their website says:

5G-XHaul proposes a converged optical and wireless network solution able to flexibly connect Small Cells to the core network. Exploiting user mobility, our solution allows the dynamic allocation of network resources to predicted and actual hotspots. To support these novel concepts, we will develop:
  • Dynamically programmable, high capacity, low latency, point-to-multipoint mm-Wave transceivers, cooperating with Sub-6 GHz systems;
  • A Time Shared Optical Network offering elastic and fine granular bandwidth allocation, cooperating with advanced passive optical networks;
  • A software-defined cognitive control plane, able to forecast traffic demand in time and space, and the ability to reconfigure network components.
The well balanced 5G-XHaul consortium of industrial and research partners with unique expertise and skills across the constituent domains of communication systems and networks will create impact through:
  • Developing novel converged optical/wireless architectures and network management algorithms for mobile scenarios;
  • Introduce advanced mm-Wave and optical transceivers and control functions;
  • Support the development of international standards through technical and technoeconomic contributions.
The differences are summarised in the document below:



It remains to be seen if C-RAN will play a big role in 5G. If yes how much of Crosshaul and XHaul will help.

Further reading:



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Saturday, November 21, 2015

'Mobile Edge Computing' (MEC) or 'Fog Computing' (fogging) and 5G & IoT


Picture Source: Cisco

The clouds are up in the sky whereas the fog is low, on the ground. This is how Fog Computing is referred to as opposed to the cloud. Fog sits at the edge (that is why edge computing) to reduce the latency and do an initial level of processing thereby reducing the amount of information that needs to be exchanged with the cloud.

The same paradigm is being used in case of 5G to refer to edge computing, which is required when we are referring to 1ms latency in certain cases.

As this whitepaper from Ovum & Eblink explains:

Mobile Edge Computing (MEC): Where new processing capabilities are introduced in the base station for new applications, with a new split of functions and a new interface between the baseband unit (BBU) and the remote radio unit (RRU).
...
Mobile Edge Computing (MEC) is an ETSI initiative, where processing and storage capabilities are placed at the base station in order to create new application and service opportunities. This new initiative is called “fog computing” where computing, storage, and network capabilities are deployed nearer to the end user.

 MEC contrasts with the centralization principles discussed above for C-RAN and Cloud RAN. Nevertheless, MEC deployments may be built upon existing C-RAN or Cloud RAN infrastructure and take advantage of the backhaul/fronthaul links that have been converted from legacy to these new centralized architectures.

 MEC is a long-term initiative and may be deployed during or after 5G if it gains support in the 5G standardization process. Although it is in contrast to existing centralization efforts, Ovum expects that MEC could follow after Cloud RAN is deployed in large scale in advanced markets. Some operators may also skip Cloud RAN and migrate from C-RAN to MEC directly, but MEC is also likely to require the structural enhancements that C-RAN and Cloud RAN will introduce into the mobile network.

 The biggest challenge facing MEC in the current state of the market is its very high costs and questionable new service/revenue opportunities. Moreover, several operators are looking to invest in C-RAN and Cloud RAN in the near future, which may require significant investment to maintain a healthy network and traffic growth. In a way, MEC is counter to the centralization principle of Centralized/Cloud RAN and Ovum expects it will only come into play when localized applications are perceived as revenue opportunities.

And similarly this Interdigital presentation explains:

Extends cloud computing and services to the edge of the network and into devices. Similar to cloud, fog provides network, compute, storage (caching) and services to end users. The distinguishing feature of Fog reduces latency & improves QoS resulting in a superior user experience

Here is a small summary of the patents with IoT and Fog Computing that has been flied.



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Tuesday, October 14, 2014

'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:



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:



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Monday, July 8, 2013

Adaptive Video Streaming: Principles, Improvements and Innovation


An Interdigital presentation from last year explains the principle of adaptive streaming very well for those who would not know how it worked.


This process of adaptation could be improved based on the quality of coverage at any particular time.

Interdigital are proposing a further enhancement of improving the adaptation further based on the User behaviour. If for example the user is far away then the quality need not be great on the device. On the other hand if the user is very close-by, the quality should be as good as it can get. They have explained it in a whitepaper for whoever is interested here.

A video showing this method is embedded below:


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Friday, September 21, 2012

Cellular-Wi-Fi Integration - technology and standardization roadmap

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Friday, June 3, 2011

Carrier Aggregation with a difference

Click on picture to enlarge

Another one from the LTE World Summit. This is from a presentation by Ariela Zeira of Interdigital.

What is being proposed is that Carrier Aggregation can use both the licensed as well as unlicensed bands but the signalling should only happen in the licensed band to keep the operator in control.

Note that this is only proposed for Small Cells / Femtocells.

The only concern that I have with this approach is that this may cause interference with the other devices using the same band (especially ISM band). So the WiFi may not work while the LTE device is aggregating this ISM band and the same goes for bluetooth.

Comments welcome!

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Thursday, August 5, 2010

Coordinated Multi-Point (CoMP): Unresolved problems

I have blogged about CoMP in quite some detail in the past. Someone recently pointed out an interesting video from Fraunhofer Heinrich Hertz Institut which is embedded below:



CoMP may be not as practical as we may think. One of the things pointed out by Dr. Ariela Zeira, InterDigital's Vice-President of Advanced Air Interfaces in the LTE World Summit was that there exists a gap between the theoretical and the practical gains of CoMP.

She went on to suggest the following as way forward for the Coordinated Multipoint acceptance in future:
  • Address root causes of gaps between academia and current feedback schemes
    • Need for improved Channel State Information (CSI) feedback resolution
    • Need for improved frequency domain precoding granularity
  • Apply CoMP where most needed and/or theoretical gains can be approached
    • Heterogeneous networks
      • Interference problem is more severe than in macro-only deployment
        • Especially for Femto Closed Subscriber Group and Pico Cells employing large cell extension
      • Lower delay spread and low mobility can be expected in Femto and Pico cells and reduce performance loss from feedback impairments
    • Relay Backhaul Channel (RBC)
      • More accurate CSI feedback from stationary relay station is possible enabling advanced non-linear precoding schemes.
      • High rank MIMO transmission will not be effective due to higher probability of Line of Sight (LOS) channel from Macro to Relay
CoMP is still probably the most promising spectral efficiency solution but need to focus on closing the gap between gains predicted by theory and those achievable with current LTE Release 8 Feedback Schemes

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Wednesday, August 4, 2010

Challenges in Mobile phone 'Ad-Hoc' Networks

Last month I blogged about a Mobile phone based Ad-Hoc network. The following slide, again from Dr. Ariela Zeira, InterDigital's Vice-President of Advanced Air Interfaces shows the possible problems in having an LTE based approach for a Mobile phone 'Ad-Hoc' network.

This kind of technology is probably quite a few years away.

Posted by Zahid Ghadialy at 7:21 AM Leave a comment...0 comments so far
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Monday, August 2, 2010

Interdigital's 'Fuzzy Cells' technology for cell edge performance improvement

Back in LTE World Summit 2010, I heard from Dr. Ariela Zeira, InterDigital's Vice-President of Advanced Air Interfaces about various things Interdigital have been working on.
One of the technologies that caught my attention was Fuzzy Cells technology to increase the cell edge rates. The following is from their press release for Mobile World Congress:
BARCELONA, Spain, Feb 15, 2010 (BUSINESS WIRE) -- InterDigital, Inc. today announced the demonstration of its "Fuzzy Cell" technology that improves cell-edge performance at the 2010 Mobile World Congress. The Fuzzy Cell technology is part of the company's comprehensive suite of "Next Generation Cellular" (NGC) innovations that combine advanced network topologies and spectrally-efficient air interface solutions for LTE-advanced and beyond.
"Many wireless operators and customers are experiencing a substantial degradation of service quality caused by the ever-growing demand for mobile data," said James J. Nolan, Executive Vice President, Research and Development, InterDigital. "We are at the forefront of developing solutions for more efficient wireless networks, a richer multimedia experience, and new mobile broadband capabilities that support operators to capture revenues from the boom in smartphones. The Fuzzy Cell fits nicely within our much broader efforts on spectrum optimization, cross-network connectivity and mobility, and intelligent data delivery techniques."
While cellular networks have become virtually ubiquitous, users continue to experience inconsistent and unpredictable performance when moving around. While this degradation is often the result of network congestion or an obstructed path of the radio waves, it is also inherent to traditional cellular deployments, whereby signals degrade towards the fringe of any given cell due to interference from neighboring cells. It is estimated that typical users experience this situation, known as being in the cell-edge, more than 50% of the time. Advancements in HSPA and LTE primarily increase peak data rates and only offer modest improvements in average performance throughout a cell.
Fuzzy Cells is a novel approach for leveraging existing resources to improve spectral efficiency and cell-edge performance. In a traditional deployment a device connects to one site at a time (even if multiple sub-bands are used at each site) and all sites use the same power levels and sector orientations for all sub-bands. In a Fuzzy Cell deployment, a device may connect to multiple sites at a time through the different sub-bands and continue to realize full system bandwidth. The power levels and sector orientations of the different sub-bands are optimized for best performance. In simpler terms, the device exploits the best combination of base station support regardless of its position, removing traditional limitations of cell or sector boundaries. Importantly, Fuzzy Cell technology can also allow gains indoors as it allows connection to more than one cell/sector at a time as available. The Fuzzy Cell technology provides additional improvement over Fractional Frequency Reuse (FFR) methods that are supported by current specifications.
The following shows the demonstration of Fuzzy cells:
I haven't heard any news recently on this technology but its an interesting concept, not sure if it would be adopted in the near term in the standards.
Posted by Zahid Ghadialy at 11:11 AM Leave a comment...1 comments so far
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