Sunday, 19 April 2015

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:


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

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.


Sunday, 12 April 2015

LTE-Hetnet (LTE-H) a.k.a. LTE Wi-Fi Link Aggregation (LWA)


We have talked about the unlicensed LTE (LTE-U), re-branded as LTE-LAA many times on this blog and the 3G4G Small Cells blog. In fact some analysts have decided to call the current Rel-12 non-standardised Rel-12 version as LTE-U and the standardised version that would be available as part of Release-13 as LTE-LAA.

There is a lot of unease in the WiFi camp because LTE-LAA may hog the 5GHz spectrum that is available as license-exempt for use of Wi-Fi and other similar (future) technologies. Even though LAA may be more efficient as claimed by some vendors, it would reduce the usage for WiFi users in that particular spectrum.

As a result, some vendors have recently proposed LTE/WiFi Link Aggregation as a new feature in Release-13. Alcatel-Lucent, Ruckus Wireless and Qualcomm have all been promoting this. In fact Qualcomm has a pre-MWC teaser video on Youtube. The demo video is embedded as follows:



The Korean operator KT was also involved in demoing this in MWC along with Samsung and Qualcomm. They have termed this feature as LTE-Hetnet or LTE-H.

The Korean analyst firm Netmanias have more detailed technical info on this topic.

Link aggregation by LTE-H demonstrated at MWC 2015 (Source: Netmanias)

As can be seen the data is split/combined in PDCP layer. While this example above shows the practical implementation using C-RAN with Remote Radio Head (RRH) and BaseBand Unit (BBU) being used, the picture at the top shows LTE Anchor in eNodeB. There would be a need for an ideal backhaul to keep latency in the eNodeB to minimum when combining cellular and WiFi data.

Comparison of link level Carrier Aggregation technologies (Source: Netmanias)

The above table shows comparison between the 3 main techniques for increasing data rates through aggregation; CA, LTE-U/LAA and LTE-H/LWA. While CA has been part of 3GPP Release-10 and is available in more of less all new LTE devices, LTE-U and LTE-H is new and would need modifications in the network as well as in the devices. LTE-H would in the end provide similar benefits to LTE-U but is a safer option from devices and spectrum point of view and would be a more agreeable solution by everyone, including the WiFi community.

A final word; last year we wrote a whitepaper laying out our vision of what 4.5G is. I think we put it simply that in 4.5G, you can use WiFi and LTE at the same time. I think LTE-H fulfills that vision much better than other proposals.

Friday, 3 April 2015

Some interesting April Fools' Day 2015 Technology Jokes

Here is a quick roundup of some interesting tech #AprilFools day jokes from the web. Click on the links to learn more

Samsung Galaxy Blade Edge - Chef's edition






Selfie Shoes by Miz Mooz - Shoefie



com.google - You can try it in chrome browser, it was working


Smartbox by Inbox: the mailbox of tomorrow, today - by Google




HTC Re-Sok - the "world's first truly smart sock"






Bing's Palm Search technology




Introducing #MotoSelfieStick - By Motorola



Twitter’s Twelfie Stick




Domino’s Domi-No-Driver Service

Iltasanomat news on April 1st 2015 (source not available): Finnish Police is having their own air forces with 250 seagulls with TETRA radio and camera


And finally, these old style pranks still work :-)

If you like them, you will enjoy the last year ones too. Here.

Saturday, 28 March 2015

Report on Spectrum Usage and Demand in the UK


Last week at work, we released a report titled "UK Spectrum Usage & Demand". The only time most people hear about spectrum is when there are some auctions going on. Often a small chunk of spectrum gets sold off for billion(s) of dollars/pounds and these surely make a headline. As I recently found out, 50% of spectrum in UK is shared and 25% is license exempt.

Anyway, this first edition of the report focuses on Public Mobile, Utilities, Business Radio and Space/Satellites. Space is becoming an important area of focus here as it is a significant contributor to the UK economy.

Anyway, the report is embedded below and is available to download from here:



Sunday, 15 March 2015

Air-Ground-Air communications in Mission Critical scenarios

In-flight communications have always fascinated me. While earlier the only possibility was to use Satellites, a hot topic for in the last few years has been Air-Ground-Air communications.

Some of you may remember that couple of years back Ericsson showed an example of using LTE in extreme conditions. The video below shows that LTE can work in these scenarios.



Now there are various acronyms being used for these type of communications but the one most commonly used is Direct-Air-to-Ground Communications (DA2GC), Air-to-Ground (A2G) and Ground-to-Air (G2A).


While for short distance communications, LTE or any cellular technology (see my post on Flying Small Cells) may be a good option, a complete solution including communication over sea would require satellite connectivity as well. As I have mentioned in a blog post before, 75Mbps connectivity would soon be possible with satellites.

For those interested in working of the Air-Ground-Air communications, would find the presentation below useful. A much detailed ECC CEPT report from last year is available here.



The next challenge is to explore whether LTE can be used for Mission Critical Air Ground Air communications. 3GPP TSG RAN recently conducted study on the feasibility and the conclusions are as follows:

There is a common understanding from companies interested in the topic that:

  1. Air-to-Ground communications can be provided using the LTE standards (rel-8 and beyond depending on the targeted scenarios).
  2. 3GPP UE RF requirements might need to be adapted
  3. It may be possible to enhance the performance of the communications with some standards changes, but these are in most cases expected to be non-fundamental optimizations
  4. Engineering and implementation adaptations are required depending on the deployment scenario. In particular, the ECC report [1] comments that from implementation point of view synchronization algorithms are to be modified compared to terrestrial mobile radio usage in order to cope with high Doppler frequency shift of the targeted scenario. In addition, some network management adaptations might be needed. From engineering perspective the Ground base station antenna adjustment has to be matched to cover indicated aircraft heights above ground up to 12 km by antenna up-tilt. It is also expected that the inter-site distances would be dominated by the altitudes to be supported [5].
  5. A2G technology using legacy LTE has been studied and successfully trialed covering different kinds of services: Surfing, downloading, e-mail transmission, use of Skype video, audio applications and Video conferencing. Related results can be found in several documents from ECC and from companies [1], [2], [3]. The trials in [1] and [2] assumed in general a dedicated spectrum, and the fact that the communications in the aircraft cabin are using WIFI or GSMOBA standards, while LTE is used for the Broadband Direct-Air-to-Ground connection between the Aircraft station and the Ground base station.
  6. It is understood that it is possible to operate A2G communications over spectrum that is shared with ground communications. However, due to interference it is expected that the ground communications would suffer from capacity losses depending on the deployment scenario. Therefore, it is recommended to operate A2G communication over a dedicated spectrum.
  7. It can be noted that ETSI studies concluded that Spectrum above 6 GHz is not appropriate for such applications [4].
  8. LTE already provides solutions to allow seamless mobility in between cells. Cells can be intended for terrestrial UEs and cells intended for A2G UEs which might operate in different frequencies.
  9. Cell range in LTE is limited by the maximum timing advance (around 100km). Larger ranges could be made possible by means of implementation adaptations. 

Sunday, 8 March 2015

LTE Category-0 low power M2M devices


While we have talked about different LTE categories, especially higher speeds, we have not yet discussed Category-0 or Cat-0 for M2M.

A recent news report stated the following:

CAT-1 and CAT-0 are lower speed and power versions of the LTE standard which dramatically extend the addressable market for carriers and chip makers alike. They introduce new IoT targeted features, extend battery operation and lower the cost of adding LTE connectivity.
“While chipsets supporting these lower categories are essential for numerous applications, including wearable devices, smart home and smart metering, there has been an industry development gap that we had anticipated two years ago,” said Eran Eshed, co-founder and vice president of marketing and business development at Altair. “We’ve worked hard to address this gap by being first to market with true CAT-1 and 0 chipsets featuring a power/size/cost combination that is a massive game-changer.”
Ericsson has an interesting presentation that talks about LTE evolution for cellular IoT. While Rel-12 Cat-0 would use the normal allocated bandwidth (upto 20MHz), Rel-13 plans further enhancements to save even more power by reducing the bandwidth to 1.4Mhz. Another possible saving of power comes from the use of Half Duplex (but its optional). There is a very interesting presentation from Mstar semiconductors on half duplex that I have blogged about here. Anyway, the presentation from Ericsson is here:



When we talk about 50 billion M2M devices, a question that I regularly ask is how many of them will be using cellular and how many will use other technologies. Its good to see that my skepticism is shared by others as well, see the tweet below.

Click on the pic.twitter.com/Z7s6wqxkBM to see the actual media.

Nokia has also got an interesting whitepaper on this topic which talks about optimizing LTE and the architectural evolution that will lead cellular LTE to become a compelling technology so that it can be widely adopted. That paper is embedded as well below.



Sunday, 1 March 2015

Monday, 23 February 2015

Static/Dynamic IP Address Allocation in LTE


I recently came across a discussion on how static and dynamic IP address are allocated in LTE for a UE. Luckily, there is a recent document from Netmanias that discussed this topic. The document is embedded below.



If you enjoyed reading the document (part 1) above, then there is a part 2 here. While in part 1, we saw that IP addresses can be either dynamic or static depending on their allocators, part 2 presents a specific case of IP address allocation – allocation in geographically-separated locations within an LTE network. In case of dynamic allocation, no matter where a user accesses, a dynamically selected P-GW dynamically allocates an IP address to the user for PDN connection. In case of static allocation, however, there is always one specific P-GW and one IP address for a user - the designated P-GW allocates a static IP address for the user’s PDN connection. A case study shows an LTE network that serves two cities as an example to describe different ways and procedures of IP address allocation, and see how they are different from each other.

Sunday, 15 February 2015

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:



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

Tuesday, 3 February 2015

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:







Anyway, here is the presentation.