Showing posts with label Deutsche Telekom. Show all posts
Showing posts with label Deutsche Telekom. Show all posts

Friday, 23 September 2016

5G New Radio (NR), Architecture options and migration from LTE

You have probably read about the demanding requirements for 5G in many of my blog posts. To meet these demanding requirements a 'next-generation radio' or 'new radio' (NR) will be introduced in time for 5G. We dont know as of yet what air interface, modulation technology, number of antennas, etc. for this NR but this slide above from Qualcomm gives an idea of what technologies will be required for this 5G NR.
The slide above gives a list of design innovations that will be required across diverse services as envisioned by 5G proponents.

It should be mentioned that Rel-10/11/12 version of LTE is referred to as LTE-Advanced and Rel-13/14 is being referred to as LTE-A Pro. Rel-15 will probably have a new name but in various discussions its being referred to as eLTE.

When first phase of 5G arrives in Rel-15, eLTE would be used for access network and EPC will still be used for core network. 5G will use NR and eventually get a new core network, probably in time for phase 2. This is often referred to as next generation core network (NGCN).

The slides below from Deutsche Telekom show their vision of how operators should migrate from eLTE to 5G.

The slides below from AT&T show their vision of LTE to 5G migration.

Eiko Seidel posted the following in 3GPP 5G standards group (i recommend you join if you want to follow technical discussions)

Summary RAN1#86 on New Radio (5G) Gothenburg, Sweden

At this meeting RAN1 delegates presented and discussed numerous evaluation results mainly in the areas of waveforms and channel coding.

Nonetheless RAN1 was not yet prepared to take many technical decisions. Most agreements are still rather general. 

First NR terminology has been defined. For describing time structures mini-slots have been introduced: a mini-slot is the smallest possible scheduling unit and smaller than a slot or a subframe.

Discussions on waveforms favored filtered and windowed OFDM. Channel coding discussions were in favor of LDPC and Turbo codes. But no decisions have been made yet.

Not having taken many decisions at this meeting, RAN1 now is behind its schedule for New Radio.
Hopefully the lag can be made up at two additional NR specific ad hoc meetings that have been scheduled for January and June 2017.

(thanks to my colleague and friend Dr. Frank Kowalewski for writing this short summary!)

Yet another post from Eiko on 3GPP RAN 3 on related topic.

The RAN3 schedule is that in February 2017 recommendations can be made for a protocol architecture.  In the meeting arguments came up by some parties that the work plan is mainly addressing U-Plane architecture and that split of C- and U-plane is not considered sufficiently. The background is that the first step will be dual connectivity with LTE using LTE RRC as control plane and some companies would like to concentrate on this initially. It looks like that a prioritization of features might happen in November timeframe. Beside UP and CP split, also the functional split between the central RAN node and the distributed RAN node is taking place for the cloud RAN fronthaul interface. Besides this, also discussion on the fronthaul interface takes place and it will be interesting to see if RAN3 will take the initiative to standardize a CPRI like interface for 5G. Basically on each of the three interfaces controversial discussion is ongoing.

Yet another basic question is, what is actually considered as a “New 5G RAN”? Is this term limited to a 5G eNB connected to the NG core? Or can it also be also an eLTE eNB with Dual Connectivity to 5G? Must this eLTE eNB be connected to the 5G core or is it already a 5G RAN when connected to the EPC? 

Finally, a slide from Qualcomm on 5G NR standardization & launch.

Wednesday, 28 May 2014

Case Study: RAN Sharing in Poland

The last post on Network sharing by NEC was surprisingly popular so I thought its worth doing a case study by Orange in Poland on how they successfully managed to share their network with T-Mobile. Full presentation embedded as follows:

Friday, 23 August 2013

How Cyber-Attacks Can Impact M2M Infrastructure

An Interesting presentation from Deutsche Telekom in the Network Security Conference which highlights some of the issues faced by the M2M infrastructure. With 500 Billion devices being predicted, security will have to be stepped up for the M2M infrastructures to work as expected. Complete presentation embedded below:

Friday, 22 October 2010

IMB and TDtv (and DVB-H)

Its long time since I blogged about TDtv. Its been quite a while since I heard about TDtv. Apparently its been superseded by IMB, aka. Integrated Mobile Broadcast.

IMB is used to stream live video and store popular content on the device for later consumption. This results in a significant offloading of data intensive traffic from existing 3G unicast networks and an improved customer experience. The multimedia client features an intuitive electronic program guide, channel grid and embedded video player for live TV viewing and video recording. All IMB applications can be quickly and cost-effectively adapted to support all major mobile operating systems and different mobile device types, including smartphones, tablets and e-readers.

IMB was defined in the 3GPP release 8 standards, and was recently endorsed by the GSMA as their preferred method for the efficient delivery of broadcast services. In June 2010, O2, Orange and Vodafone – three of the five major UK mobile operators – announced that they have teamed up for a three-month trial that will explore IMB wireless technology within a tranche of 3G TDD spectrum.

This spectrum already forms part of the 3G licenses held by many European mobile operators, but has remained largely unused because of a lack of appropriate technology. Currently, 3G TDD spectrum is available to over 150 operators across 60 countries, covering more than half a billion subscribers. IMB enables spectrally efficient delivery of broadcast services in the TDD spectrum based on techniques that are aligned with existing FDD WCDMA standards. This enables a smooth handover between IMB and existing 3G networks.

Issues that previously limited uptake of IMB, or IPWireless' tdTV system, have now all been addressed. Namely, the standard now allows for smooth handover between IMB and unicast delivery; has the potential to be integrated onto a single W-CDMA chip rather than requiring a separate chip; and has resolved interference issues with FDD W-CDMA, at least for spectrum in the 1900MHz to 1910MHz range.

IP Wireless already had a trial at Orange and T-Mobile in the UK (which have just agreed to merge), but in that pilot each 5MHz segment only gave rise to 14 TV channels per operator. The new standard could support 40 separate TV channels if two operators shared their TDD spectrum.

The GSMA announced its support and is backed up with additional support from both IPWireless and Ericsson as well as operators Orange, Softbank and Telstra.

There have been recently quite a few bad news for DVB-H and on top of that IP Wireless has announced that Samsung is going to be releasing phones with IMB support so it may be that we will see IMB sometime next year.

The GSMA paper that details IMB service scenarios and System requirements is embedded below:

Wednesday, 10 June 2009

VoLGA: Bringing Voice to LTE

Voice is becoming an Important issue for seamless introduction of LTE services. Even though most people think that LTE will start with the Broadband Dongles, it is important to resolve the issue sooner rather than later.

VoLGA Forum is one such body proposing a solution and its backed by quite a few well known industry players.

In the LTE World Summit, Franz Seiser of T-Mobile Germany spoke about VoLGA. Here is a summary from his presentation:

In order to ensure LTE will be used as much as possible, voice-and messaging services need to be supported on LTE networks in high quality asearly as possible.

The main Drivers being:
  • Ensure acceptance of LTE as an possible next generation PLMN
  • Shift traffic to new network as fast as possible
  • Avoid price competition with DSL
The industry needs a stable, scalable voice and SMS solution forLTE:
  • delivering a seamless user experience (voice hand-over to existing 2G/3G networks)
  • with proven, commercial quality
  • availability in 2010 (SMS) /2011 (voice) latest

In a post earlier, I discussed about the possible voice options for LTE and that generated quite a discussion relating to GAN. Recently Dean Bubley and Martin Sauter have covered this VoLGA issue and in general Voice over LTE in far more detail than I have earlier or even in this post. Please see the links at the bottom to read their post details.

Specified 3GPP solutions for Voice/SMS in LTE do not meet all requirements because:

CS Fallback ruled out due to customer experience and non-LTE usage

  • issues with customer experience (call set-up time increase >1.5sec., no parallel voice/data if legacy network is 2G w/o DTM)
  • not using LTE radio for voice
  • requires changes to Rel-4 architecture MSC-Servers
  • has much more impacts than originally envisaged

IMS based solution has very high complexity; availability and stability notfeasible in time, roaming eco-system is not yet existent

  • solution would consist of IMS platform, various application servers and a major upgrade/change to Rel-4 architecture MSC-Servers
  • no eco-system in place yet for IMS voice/SMS roaming and interconnect (only GPRS data or CS eco-systems are available today)
  • solution requires updates/changes to quite many IT systems and processes as well

Key Objectives for Voice/SMS over LTE Solution is to Re-use as much as possible of existing systems, mechanism and eco-system while avoiding proprietary extensions to 3GPP nodes

  • build upon existing Rel-4 CS network and investments
  • “do not touch the MSC”
  • build upon fully 3GPP compliant Rel-8 EPC/LTE network
  • re-use existing CS roaming/inter-connect regime
  • minimise impact on UE, especially on user-interface

As a result, the simplest solution is “Voice over LTE Generic Access” or VoLGA

What is VoLGA?
  • A technological approach for delivering voice and SMS services over LTE access networks
  • Leverages a mobile operator’s existing core voice network
  • Derived from the existing 3GPP GAN standard

What is the VoLGA Forum?

A group of companies working to…

  • Leverage collective technical skills to define VoLGA specifications
  • Publish proposed specifications via the VoLGA Forum web site (coming soon)
  • Facilitate the easy adoption of VoLGA technology by other vendors and operators

The group is open to interested parties in the mobile community

The main Highlights of VoLGA are:

  • Full service transparency
  • Supports all circuit services over LTE
  • Supports IMS RCS and combinational services (CS+IMS) over LTE
  • Supports handover of active calls between LTE and GSM/UMTS
  • Supports expected LTE femtocell deployments
    • Low risk, low investment
    • Based on well proven 3GPP GAN standard
    • Requires no change to existing MSCs and operational systems
    • Conserves existing, extensive voice interconnection regime

    To keep things simple, VoLGA is the best option available at the moment.

    Further Reading:

    You can search multiple blogs (including mine) in a single search via the 3G4G search here. (Search at the bottom of the page).