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Showing posts with label LTE. Show all posts
Showing posts with label LTE. Show all posts

Friday, 21 November 2014

In-flight broadband connectivity service with speeds up to 75Mbps


Came across the following Inmarsat press release:

The new network represents two world-beating achievements for Inmarsat and its partners. It will be the world’s first truly hybrid aviation network, consisting of an S-band satellite (Europasat), constructed by Thales Alenia Space, and a Europe-wide S-band ground network. Over the integrated network, based on state-of-the-art LTE technology and access to sufficient spectrum resources, Inmarsat will be offering airlines the world’s fastest in-flight broadband connectivity service with speeds up to 75Mbps, far in excess of the limited capabilities of North American ATG systems.
Alcatel-Lucent and Inmarsat will work together to develop the ground infrastructure component of the new Europe-wide network. Alcatel-Lucent has proven expertise in the development of 4G LTE-based air-to-ground technology and was the world’s first company to field trial this technology in 2011. The initial contract awarded to Alcatel-Lucent will see the global telecommunications equipment company adapting their existing 4G LTE technology to support the S-band spectrum.
Recently Christophe WILHELM, Senior VP Strategy & Innovation, Thales Alenia Space gave a presentation in the Digiworld Summit 2014.



His presentation is above and the video is as follows. Please forward to 1:36:00 to watch his part



Wednesday, 5 November 2014

2015 will finally be the year of Voice over LTE (VoLTE)


On 4th Nov. 2009, the One Voice initiative was published by 12 companies including AT&T, Orange, Telefonica, TeliaSonera, Verizon, Vodafone, Alcatel-Lucent, Ericsson, Nokia Siemens Networks, Nokia, Samsung and Sony Ericsson. These all agreed that the IMS based solution, as defined by 3GPP, is the most applicable approach to meet their consumers expectations for service quality, reliability and availability when moving from existing CS based voice services to IP based LTE services.

On 15th Feb 2010, GSMA announced that it has adopted the work of the One Voice initiative to drive the global mobile industry towards a standard way of delivering voice and messaging services for LTE. The GSMA’s VoLTE initiative was supported by more than 40 organisations from across the mobile ecosystem, including many of the world’s leading mobile communication service providers, handset manufacturers and equipment vendors, all of whom support the principle of a single, IMS-based voice solution for next-generation mobile broadband networks. This announcement was also supported by 3GPP, Next Generation Mobile Networks alliance (NGMN) and the International Multimedia Teleconferencing Consortium (IMTC).

GSMA has produces various reference documents that map to the 3GPP standards documents as can be seen above.



As per GSA71 operators are investing in VoLTE studies, trials or deployments, including 11 that have commercially launched HD voice service. The number of HD voice launches enabled by VoLTE is forecast to reach 19 by end-2014 and then double in 2015. In July 2014 GSA confirmed 92 smartphones (including carrier and frequency variants) support VoLTE, including products by Asus, Huawei, LG, Pantech, Samsung and Sony Mobile. The newly-announced Apple iPhone 6 & 6 Plus models support VoLTE.

Things are also moving quickly with many operators who have announced VoLTE launches and are getting more confident day by day. Du, Dubai recently announced Nokia as VoLTE partner. KDDI, Japan is launching au VoLTE in December. Telstra, Australia has already been doing trials and plans to launch VoLTE network in 2015. Finally, Verizon and AT&T will have interoperable VoLTE calls in 2015.

Below is my summary from the LTE Voice Summit 2014. Let me know if you like it.


Saturday, 1 November 2014

4G Security and EPC Threats for LTE

This one is from the LTE World Summit 2014. Even though I was not there for this, I think this has some useful information about the 4G/LTE Security. Presentation as follows:


Sunday, 19 October 2014

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:


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:

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. 

Thursday, 18 September 2014

Update on Public Safety and Mission Critical communications

Its been a while since I wrote about Public Safety and Mission Critical communications, so here is a quick summary.


Iain Sharp have a good overview of whats happening in the standards in the LTE World Summit back in June. Embedded below is his complete presentation.



There is another slightly older presentation that I also thought was worthwhile adding here.

There is a lot of discussion centred around the use of commercial networks for mission critical communications, mainly die to cost. While this may make sense to an extent, there should be procedures put in place to give priority to public safety in case of emergency.



We are planning to run a one day training in Jan 2015 on public safety. If this is of interest to you then please get in touch with me for more details.

x-o-x-o-x-o-x-o-x-o-x-o-x
After the post someone brought these links to my attention so I am adding them below:

Tuesday, 9 September 2014

LTE Device-to-device (D2D) Use Cases

Device-to-device is a popular topic. I wrote a post, back in March on LTE-Radar (another name) which has already had 10K+ views. Another post in Jan, last year has had over 13K views. In the LTE World Summit, Thomas Henze from Deutsche Telekom AG presented some use cases of 'proximity services via LTE device broadcast'


While there are some interesting use cases in his presentation (embedded below), I am not sure that they will necessarily achieve success overnight. While it would be great to have a standardised solution for applications that rely on proximity services, the apps have already come up with their own solutions in the meantime.

Image iTunes

The dating app Tinder, for example, finds a date near where you are. It relies on GPS and I agree that some people would say that GPS consumes more power but its already available today.



Another example is "Nearby Friends" from Facebook that allows to find your friends if they are nearby, perfect for a day when you have nothing better to do.

With an App, I can be sure that my location is being shared only for one App. With a standardised solution, all my Apps have info about location that I may not necessarily want. There are pros and cons, not sure which will win here.

Anyway, the complete presentation is embedded below:



For anyone interested in going a bit more in detail about D2D, please check this excellent article by Dr. Alastair Bryon, titled "Opportunities and threats from LTE Device-to-Device (D2D) communication"

Do let me know what you think about the use cases.

Sunday, 24 August 2014

New LTE-A UE Category 9 and 10 in Rel-11

Its been a while since we saw any new UE categories coming but then I noticed some new categories came earlier this year for Release-11. The latest 3TPP TS 36.306 have these new Category 9 and Category 10 as follows.
For those who are aware of the categories of the UE's being used in practice may be aware that the most common ones have been 'Category 3' with 100Mbps max in DL and 50Mbps max in UL. The new 'Cat. 4' devices are becoming more common as more manufacturers start bringing these devices to the market. They support 150Mbps max in DL and 50Mbps max in UL. Neither of them supports Carrier Aggregation.

Having said that, a lot of Cat. 4 devices that we may use in testing actually supports carrier aggregation. The next most popular devices soon to be hitting the market is Cat. 6 UE's with 300Mbps max in DL and 50Mbps max in UL. Category 6 UE's support 2 x 20MHz CA in downlink hence you can say that they can combine 2 x Cat. 4 UE's in DL but they do not support CA in uplink hence the UL part remains the same as Cat. 4 device.

Cat. 9 and 10 are interesting case as Car. 8 was already defined earlier to meet IMT-A requirement as shown below.


To meet IMT-A requirements of peak data rates of 1Gbps in UL and DL, LTE-A had to define category 8 with 5 band CA and 8x8 MIMO to be able to provide 3Gbps max in DL and 1.5Gbps max in UL. No one sees this device becoming a reality in the short term.

The new categories will have to be defined from Cat. 9 onwards.

Cat. 9 allows 3 x Cat. 4 device CA in the downlink to have the maximum possible downlink data rates of 450Mbps but there is no CA in the uplink. As a result, the UL is still 50Mbps max. Cat. 10 allows carrier aggregation in the uplink for upto 2 bands which would result in 100Mbps max in UL.

The LG space website gives a better representation of the same information above which is shown below:



A UE category 9 transmits Rel 11 category 9 + Rel 10 category 6 + Rel 8 category 4

With Release-12 due to be finalised later in the year, we may see new UE categories being defined further.

Saturday, 9 August 2014

Multi-Frequency Band Indicator (MFBI)

I am sure we all know that LTE bands have been growing, every few months. All the 32 bands for FDD have now been defined. The 33rd band is where TDD bands start. What if we now want to have more FDD bands? Well, we will have to wait to fix that problem.

Picture Source: LG Space

Anyway, as can be seen in the above picture, some of the frequency bands overlap with each other. Now you may have a UE thats camped onto one frequency that is overlapping in different bands. Wouldn't it be useful to let the UE know that you are camped in more than one band and you can change it to another frequency which may be a different band but you were already on it in the first place (it may sound confusing).

Here is a much simpler table from the specs that show that when a UE is camped on band 5, it may also be camped on bands 18, 19 and 26. Remember the complete bands may not be overlapping but may only be partially overlapping.

An example could be Sprint that used Band 38 TDD (BW 50MHz) for its legacy devices but is now able to use Band 41 (BW 194MHz) as well. The legacy devices may not work on Band 41 but the new devices can use much wider band 41. So the transmission would still say Band 38 but the new devices can be informed of Band 41 using the System Information Block Type 1. AT&T has a similar problem with Band 12 and 17.

Even though this was implemented in Release-8, it came as a part of Late Non-critical extensions. Its a release independent feature but not all UE's and Network have implemented it. The UE indicates the support for MFBI using the FGI (Feature Group Indicator) bits. 

Saturday, 26 July 2014

Observed Time Difference Of Arrival (OTDOA) Positioning in LTE

Its been a while I wrote anything on Positioning. The network architecture for the positioning entities can be seen from my old blog post here
Qualcomm has recently released a whitepaper on the OTDOA (Observed Time Difference Of Arrival) positioning. Its quite a detailed paper with lots of technical insights.

There is also signalling and example of how reference signals are used for OTDOA calculation. Have a look at the whitepaper for detail, embedded below.



Sunday, 20 July 2014

LA-LTE and LAA


Recently came across a presentation by Ericsson where they used the term LA-LTE. I asked a few colleagues if they knew or could guess what it means and they all drew blank. I have been blogging about Unlicensed LTE (a.k.a. LTE-U) on the Small Cells blog here. This is a re-branding of LTE-U

LA-LTE stands for 'Licensed Access' LTE. In fact the term that has now been adopted in a recent 3GPP workshop (details below) is Licensed Assisted Access (LAA).

Couple of months back I blogged in detail about LTE-U here. Since then, 3GPP held a workshop where some of the things I mentioned got officially discussed. In case you want to know more, details here. I have to mention that the operator community is quite split on whether this is a better approach or aggregating Wi-Fi with cellular a better approach.

The Wi-Fi community on the other hand is unhappy with this approach. If cellular operators start using their spectrum than it means less spectrum for them to use. I wrote a post on the usage of Dynamic Spectrum Access (DSA) Techniques that would be used in such cases to make sure that Wi-Fi and cellular usage does not happen at the same time, leading to interference.

Here is a presentation from the LTE-U workshop on Use cases and scenarios, not very detailed though.



Finally, the summary presentation of the workshop. As it says on the final slide "The current SI proposal focuses on carrier aggregation operations and uses the acronym LAA (Licensed Assisted Access)", you would be seeing more of LAA.


Sunday, 13 July 2014

Case Study: LTE for real time news gathering by Sky News

Back in May, I had the pleasure of listening to a talk by Richard Pattison from Sky News where he talked about how they have managed to start replacing their Satellite trucks (which are extremely expensive to own and run) with the new solutions using LTE.

One of the advantage of LTE over 3G/HSPA+ is that the uplink is as good as the downlink which wasn't really the case in earlier generations. What this means is that you can use your phone to do a live video call and use that for broadcasting of real time information. The Sky News Tech team has some interesting tweets on this.




An example of the video quality could be seen from this clip here:

The Dejero App is an interesting one that can allow bonding of Cellular + WiFi and provide a combined data rate.


I was having a discussion yesterday on Twitter because we term this bonded cellular and WiFi as 4.5G. There are many proprietary solutions available for using them together but the standardised one is coming in standards soon.

Sky news have managed to set up new standards by having 12 feeds simultaneously broadcasting  (all based on Iphones and Ipads) during the European elections.



All this has been possible due to an amazing 4G network by EE and being able to negotiate a 500GB (0.5TB) data package.


Anyway, you can read the complete paper below:



Friday, 4 July 2014

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:


Wednesday, 2 July 2014

Case Study: Migrating from WiMAX to TD-LTE



I was glad to hear this case study by Mike Stacey where they have a WiMAX network already deployed and are in process of moving to TD-LTE. Along with the technical issues there are also business and customer issues that need to be taken into account while doing this technology swap. Surprisingly 3.5GHz is also not a very popular band because there are very few deployments in this spectrum. On the other hand, most of the companies worldwide that have been able to get their hands on this spectrum, generally got a big chunk (60-100MHz) so they would be able to do CA easily (bar the technical issues of Intra-band interference).

Anyway, the presentation is embedded below. Hope you find it useful. If you know of similar experiences, please feel free to add them in the comments.


Monday, 30 June 2014

4.5G: Integration of LTE and Wi-Fi networks


With LTE-A getting ready to meet the IMT-Advanced requirements and fulfilling the role of promised '4G', we believe the next phase of evolution before 5G will be successful interworking of LTE and Wi-Fi networks.


This whitepaper (embedded below) explores this feature, we call 4.5G, in detail.

Understanding WLAN offload in cellular networks by Anritsu

We are very thankful to Anritsu for kindly sponsoring this whitepaper. They have their own whitepaper on this topic which is also worth a read, available here.



Let us know what you think about this.

Saturday, 28 June 2014

EE: The Implications of RAN Architecture Evolution for Transport Networks


Here is a presentation by Andy Sutton, EE from the recent LTE World Summit 2014. Unfortunately the event was too big to be present in all presentations but in his own words, "As always the bullet points don’t tell the full story as there’s considerable narrative that goes with this, however it does stress some major themes."

Slides embedded below, can be downloaded from Slideshare:


Friday, 27 June 2014

Voice over WiFi (VoWiFi)


One of the changes that I have noticed in the last year is that some of the operators who have been opposed to WiFi in the past have not only embraced it but are now trying to monopolise the same WiFi spectrum they billed as interference prone. Personally, I think the future of Wi-Fi is not just offloading but also working together with LTE. We are billing this as 4.5G and have recently produced a whitepaper, available here.

There has been a flurry of activity on Voice over Wi-Fi in the last few months. Recently the UK operators '3' and EE announced that they are both allowing WiFi calling and SMS. While '3' customers will have to use an OTT app for the time being, EE customers will experience this seamlessly.

I heard Taqua in the recent LTE World Summit talking about their solution and have offered to share their slides (embedded below). It was interesting to find out while having a discussion with them that their solution supports 'hand-in' and 'hand-out'. This takes away a major advantage that Small Cells offered, seamless roaming. Anyway, feel free to let me know of you have any opinion on this topic


Wednesday, 25 June 2014

Diamater: Market Status, Roaming, NFV and Case Studies

Some more interesting presentations from the Signalling Focus Day of LTE World Summit. Good overview of market by Greg Collins of Exact ventures is embedded below.





A good presentation by Tieto where they presented some good case studies for Diameter Interworking. Presentation embedded below:




The final presentation by Diametriq is very interesting because they presented interesting way of mining the control plane. Thee case study presented was of a 'silent roamer' who is not going to spend money while roaming because he is not sure how much money is spent. This can be exploited by the operator to offer flat packages, 1 day pass, etc. to get some revenue from these roamers. Their presentation included some animations that cannot be shown while being embedded. Please download the PPT from Slideshare to view them.


Monday, 23 June 2014

LTE Roaming using IPX


A very interesting presentation from Raphaël Glatt of Bics in the Signalling Focus Day of LTE World Summit 2014. IPX is probably the most popular solution as its already being used by many operators for roaming agreements. Anyway, his presentation was the most detailed one I have come across and he was happy to share it with me for this blog. His complete presentation is embedded below:



Wednesday, 21 May 2014

Connected and Autonomous Car Revolution

Last week we had the Automotive and Transport SIG event in Cambridge Wireless. There is already some good writeup on that event here and here. In this post my interest in looking at the technologies discussed.

R&S (who were the sponsors) gave their introduction presentation quite well highlighting the need and approaches for the connected car. He also introduced the IEEE 802.11p to the group.

As per Wikipedia, "IEEE 802.11p is an approved amendment to the IEEE 802.11 standard to add wireless access in vehicular environments (WAVE), a vehicular communication system. It defines enhancements to 802.11 (the basis of products marketed as Wi-Fi) required to support Intelligent Transportation Systems (ITS) applications. This includes data exchange between high-speed vehicles and between the vehicles and the roadside infrastructure in the licensed ITS band of 5.9 GHz (5.85-5.925 GHz). IEEE 1609 is a higher layer standard based on the IEEE 802.11p."

Back in December, Dr. Paul Martin did an equally useful presentation in the Mobile Broadband SIG and his presentation is equally relevant here as he introduced the different terms live V2X, V2i, V2V, V2P, etc. I have embedded his presentation below:



Roger Lanctot from Strategy Analytics, gave us some interesting facts and figures. Being based in the US, he was able to give us the view of both US as well as Europe. According to him, “LTE is the greatest source of change in value proposition and user experience for the customer and car maker. Bluetooth, Wi-Fi, NFC and satellite connectivity are all playing a role, but LTE deployment is the biggest wave sweeping the connected car, creating opportunities for new technologies and applications.” His officially released presentation is embedded below (which is much smaller than his presentation on that day.



There were also interesting presentations that I have not embedded but other may find useful. One was from Mike Short, VP of Telefonica and the other was from Dr. Ireri Ibarra of MIRA.


The final presentation by Martin Green of Visteon highlighted some interesting discussions regarding handovers that may be required when the vehicle (and the passengers inside) is moving between different access networks. I for one believe that this will not be an issue as there may be ways to work the priorities of access networks out. Anyway, his presentation included some useful nuggets and its embedded below:


Friday, 18 April 2014

International LTE Data and VoLTE Roaming - NTT Docomo


Quick recap of the Bearer Architecture: Remember the interface between S-GW and P-GW is known as S5/S8. S5 in case the S-GW and P-GW are part of the same network (non-roaming case) and S8 in case where P-GW belongs to another network than S-GW (roaming case). The S5/S8 interfaces are generally exactly the same. There is a possibility of different types of S5/S8 interfaces like GTP based and PMIP based but lets not discuss that here.

NTT Docomo published an excellent article in their magazine recently showing the different approaches to International Data roaming.


The different scenarios above are based on the guidelines provided in GSMA PRD IR.88. Each operator has to adopt one of the scenarios above, NTT Docomo has selected scenario 4. The Home PLMN (HPLMN) and the Visited PLMN (VPLMN) connect via IP eXchange (IPX).


As can be seen above, the MME in VPLMN communicates with HSS in HPLMN using Diameter Edge Agent (DEA).



Finally, it is well known that NTT Docomo is not launching VoLTE untill 2015. The above is their proposal on how they handle VoLTE while in Japan and when roaming.

The paper is an interesting read, embedded below:



Another article worth a read is the VoLTE roaming with RAVEL here.