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Telia to launch LTE in Finland next month, then Denmark next year

Having gone live in parts of Sweden, Norway and Uzkekistan, Telia will start its Finnish roll-out from next month and Denmark next year.  In Denmark, TDC aims to pip Telia to the post, and has awarded a RAN and core contract for LTE to Ericsson.

– Rethink Wireless

 

 

Why does it seem so difficult for operators to agree on similar capacity requirements?

We read a lot about the predicted growth in mobile data traffic and there has been at least 2 years of significant growth to allow operators to get a sense of continued growth into the future. The uptake of smartphones and dongles to drive this growth appears to be unquenchable – a recent prediction suggests that data per smartphone will grow by 7x by 2015 . Whilst the ability of an individual operator to accurately predict or anticipate traffic over a wide area is challenging given the uncertainties of customer demand, why does it appear to be so difficult for operators to agree on demand and therefore capacity requirements in a “closed” environment such as an airport, stadium or shopping centre. In a stadium environment the maximum number of people is known and whilst the profile of the users may change depending on what is taking place (football, rugby, concert etc.) should there really be a 2 or 3 fold difference between what the capacity requirements for different operators is, given roughly equal market shares?

Real Wireless comment on the reality of mobile network capacity growth at Industry Outlook Conference

On November 25th, Real Wireless’ Simon Saunders is speaking on a panel session at Informa’s Industry Outlook 2011: Telecoms and Media in the Internet Age. Our session is at 14:10 and will discuss: “Network Strategies for Addressing the Exponential Growth in Mobile Data Traffic: What is the Role of Technology as Opposed to Pricing Solutions?”

We plan to clarify our view that, contrary to some industry doom-mongers, mobile operators have plenty of options for economically expanding their network capacity to meet future demand without resorting to throttle demanding via unattractive pricing.

The panel comprises:

Moderator:

  • Kris Szaniawski – Principal Analyst, Informa Telecoms & Media

Panellists:

  • Ed Candy – CTO, 3 UK
  • Andy Macleod – Director Group Networks, Vodafone UK
  • Simon Saunders – Independent Consultant
  • Dimitris Mavrakis – Senior Analyst, Informa Telecoms & Media

See http://www.industry-outlook.com/ for further details.

White paper: Strategies for mobile network capacity expansion



One of the hottest topics in the mobile industry is the need for more capacity to serve the  growing  quantities of  data emerging from 3G-connected devices like iPhones, iPads, Android devices and 3G modems . Some commentators are keen to paint this as a crisis, leading to the imminent collapse of mobile networks. We have taken a more sober look at the available capacity options and concluded there is scope to meet the demand now and in the future – if you know where to look. See our free white paper Strategies for mobile network capacity expansion for details.

 

The changing face of the femtocell ecosystem – who is best placed to succeed?

The femtocell industry has traditionally been dominated by start up companies dedicated to building small cell products such as 3 Way Networks, Ubiquisys and ip.access.  However, as wireless broadband traffic forecasts have continued to highlight trends such as the high demand for capacity indoors and a high proportion of traffic being generated by a small proportion of users the case for smaller cells has gathered support.  This was demonstrated at Broadband World Forum last week where operators agreed that capacity bottlenecks won’t be solved by spectrum efficiency improvements of 4G alone and that smaller cells will be needed [1].  Recent auctions of spectrum at both 800MHz and 2.6GHz in Germany have also facilitated plans for a two tier network topology, further fuelling the interest in smaller cells [2].

This growing interest in smaller cells has led to some big industry players joining the traditionally niche and UK centric femtocell ecosystem.  For example in March this year Qualcomm announced that it would be providing its femtocell chipset to ZTE [3].  Most recently Broadcom has entered the market by purchasing the Israeli femtocell chipset vendor Percello [4].  Freescale has also recently joined the Femto Forum and has announced their intention to develop LTE System on a Chip (SoC) platforms suitable for femtocells [5].   This is perhaps an expected development to match the femtocell platform product range already launched by FSL’s rivals TI.


Figure 1 – The femtocell ecosystem with supply links shown

With these changes to the femtocell ecosystem, who is now best placed to succeed in this growing market?  While only time will tell exactly who the big winners and losers of the femtocell industry will be we can make some observations about what has worked well so far such as:

  • Being first doesn’t necessarily guarantee success
  • It’s good to know your niche in the ecosystem and to stick to it
  • Know your target market; home or enterprise

Being first doesn’t necessarily guarantee success – The first UMTS femtocell access point product was produced by Cambridge based start up 3 Way Networks [6].   The product successfully attracted interest from investors and 3 Way Networks was acquired by Airvana in 2007 [7].  However, being first to market unfortunately hasn’t guaranteed success and Airvana recently announced that they are discontinuing their UMTS femtocell product range [8]

It’s good to know your niche in the ecosystem and to stick to it– One of the success stories of the femtocell industry to date is the rise of picoChip.  Established initially as a flexible baseband processing solution for software defined radio platforms, picoChip were quick to pick up on the promise of femtocells and have focused their product roadmap around producing a cost optimised off the shelf femtocell PHY chipset with an onboard processor to allow femtocell access point vendors to add their own higher layer stack and interface to the femtocell gateway.  Making a clear decision to be a chipset vendor and sticking to this vision has also produced dividends for Percello who were recently acquired by Broadcom.

Know your target market; home or enterprise– Traditionally the femtocell industry has focused on the home market.  However, more recently femtocell vendors have turned their attention to the enterprise market which requires providing coverage to more users and over a larger cell radius in an office rather than home environment.   These are two very different markets with different cost considerations and technical challenges.  In the residential femtocell market a low unit cost is key and backhaul restrictions are a big concern.  The enterprise market is not as sensitive to cost and while backhaul may not be as much of a concern in an office environment the number of users and throughput will be.  Vendors trying to serve both markets may well be left with comprises in their product that a more focused vendor hasn’t had to make.

Over the next year it will be interesting to watch how the increasingly congested femtocell ecosystem evolves and whether the smaller vendors with more experience in this sector will be able to navigate their way past the challenges of the better known but relative newcomers to the femtocell industry.

References

[1] European telcos say LTE will not solve capacity crunch, http://www.totaltele.com/view.aspx?ID=459850&G=1&C=4&Page=0

[2] German mega mobile spectrum auction ends, http://realwireless4g.wordpress.com/2010/05/20/german-mega-mobile-spectrum-auction-ends/

[3] Qualcomm Snags First Femto Wins, http://www.lightreading.com/document.asp?doc_id=189633

[4] Broadcom Corporation to Acquire Percello Ltd., http://www.broadcom.com/press/release.php?id=s523205

[5] Freescale plans basestation-on-chip, http://www.eetimes.com/electronics-news/4200872/Freescale-plans-basestation-on-chip-

[6] World’s First Commercially Available 3G Femto Cell, http://www.3g.co.uk/PR/Feb2007/4221.htm

[7 ] Airvana Acquires 3Way Networks, http://www.airvanacom.com/products/news_378.htm

[8] Airvana’s Femtocell Market Focus, http://blog.airvana.com/airvana-blog/2010/09/airvanas-femtocell-market-focus.html

The LTE seminars of old

I attended an LTE seminar in October which was hosted by a number of key industry players with an intent to maintain the momentum of promoting the new technology.

The theme of the event was very much in the realms of how LTE technology features enhance performance of mobile broadband systems and how the expected increase in data demand can be addressed using LTE. The seminar was very informative and included a clear exposition of all the key component technologies for LTE such as OFDMA, MIMO and scheduling, highlighting the differences between those and the WCDMA technologies used in UMTS and HSPA.

However, most of the information was based on specifications and theoretical performance. LTE is now being deployed in markets around the world. For example, Verizon is reportedly due to announce its launch of LTE in over 30 markets in the US on 15th November and Telia Sonera’s network in Stockholm has been operational for almost a year. Our 4G blog provides much more detail of market progress.

There is now a clear appetite for knowledge of how LTE operates within a live or trial environment such as: what are real data rates being achieved under live conditions compared to those of simulations or the ‘headline’ peak rates. With my colleagues at Real Wireless I am now working extensively in this area, including engaging with the industry on projects such as our recently-announced study for Ofcom and several other projects for vendors, operators and potential users.

Now that the candidate radio interface technologies have been accepted by the ITU for IMT-Advanced for both LTE-Advanced and WiMAX 2 we will start to see much more information being provided in seminars and conferences on the real-world performance of the new features of LTE, including the data rates and spectrum efficiencies which users and operators can expect from LTE in practice.

Whither a path loss model for intelligent relays?

Book cover

Mobile network subscribers expect to have coverage. Whether it is for making calls or sending a text, or for accessing their favourite applications, they expect a nearby network to provide them with high quality service. Yet the network operators leave coverage gaps, especially in remote locations (rural areas) and underground levels (basements of department stores, London Underground).

Relays are an alternative solution to adding more base stations, which extend the network’s coverage (while not providing the additional capacity available from femtocells). Intelligent relays have attracted signifcant attention for early LTE deployments, when the network operators aim to provide wide area coverage yet LTE subscribers will be few.

My book on relaying technology, entitled “Low-Height Channel Modelling with Application to Multihop UMTS: A statistical model that characterises the low-height channel and application of this model to a multihop UMTS”, provides propagation tools that can be readily applied to link budget calculations for networks that employ relays, whether for 3G or 4G systems. The propagation mechanisms that apply to the relay-user link are distinctly different from conventional links because of the low antenna heights of both terminals, which traditional path loss models do not cover.

The suggested low-height mean path-loss, shadowing, and fast fading models were tuned with two measurement campaigns in urban and suburban locations in the UK, covering frequencies up to 2.1GHz. The performance of the models was evaluated with independent data sets. The book is available in Amazon and I’d be pleased to answer queries on this topic.

Femtocells – A quiet revolution in mobile communications

The latest edition of Ingenia – the magazine of the Royal Academy of Engineering – includes an article by Simon Saunders on the current state of play of the femtocell market and some of the emerging new trends. Download it from here.

Online in-building wireless certification programme launches, featuring Real Wireless

Our contributions to iBwave’s certification programme have now been incorporated in the online training version, launched today.

As we commented in the foreword to one of the few books on in-building radio design :

“The industry desperately needs best-practice techniques to be shared amongst a wider base of individuals to serve the growing demand – there are not enough engineers for the buildings requiring service – and for these techniques to become standardised in order to drive down costs, improve reliability and drive volumes.”

An accessible certification programme is an important step towards professionalising   the in-building wireless industry and we applaud iBwave’s actions on this. We hope the programme becomes as widely accepted as the Cisco certifications have become for the internet industry.

Antennagate: the real engineering behind the iPhone 4 antenna issue

One of our newest associates, Robert Thorpe, is a real mobile antenna expert. He took some time to explain the reality of the much-reported iPhone 4 antenna saga:

Antenna engineering is rarely big news, but the problems with the Apple iPhone 4 brought it into the spotlight.  It’s highlighted issues that many smaller businesses designing wireless products struggle with.

Back in June Apple announced the iPhone 4, in his keynote speech Steve Jobs promoted the new antenna design.  I was asked to comment on the antenna for an article on the Wall Street Journal website.  The journalist sent me a long list of questions and I replied with a long list of comments.  There was only one bit that was quoted directly: “This is a very difficult thing to do”.

New ideas in antenna technology are difficult to get right the first time.  It’s normal for a new type of antenna to be tried out on a low-volume product first before it is used on a high volume product.  Apple decided to skip that step and implement a new type of design on a high volume product, that was a very brave decision.
The conventional type of internal antenna for cellphones is the Planar Inverted-F Antenna – the PIFA.  The PIFA is normally placed at the top or the bottom of the handset.  The PIFA is a flat piece of conductor cut into a shape, it is placed above the handset’s PCB which provides a groundplane.  It has a feed pin which connects the RF feed to the PIFA and a ground pin that connects the PIFA to ground.
For a PIFA the distance between the groundplane and the antenna strongly affects the impedance bandwidth.  The greater the distance the greater the bandwidth that can be achieved.  In a handset that distance is directly related to the thickness of the phone.  That is the major problem with the PIFA, if more bands are needed then a thicker PIFA is needed, which in turn requires a thicker handset.  Modern cellphones must cover five bands to work internationally.  The effect this has on the profile of the handset can be clearly seen in the HTC Legend and the Samsung Galaxy SGS, both have a “power bulge” to accomodate the antenna.
For Apple though aesthetics and good product design are very important.  I think it was this that led to them to adopt radically different antenna technology.  They wanted to make a thin five band handset and they got a group of antenna engineers to research the problem until they found an answer.  A search through Apple’s patents shows that they’ve been working on this research program for several years.
Apple haven’t revealed exactly what sort of antenna they’ve used in the iPhone 4.  They have said that the outer frame around the edge of the handset forms the antenna, but they haven’t said exactly how this was done.  However, their patent applications are revealing.  In this post, I explain how two of Apple’s patent applications suggest that the antenna is a form of slot antenna.
As soon as the iPhone 4 was released rumours on the internet began about poor performance.  Only a couple of days after it was released there were dozens of videos on YouTube showing the problem.  Most of the videos showed something similar, when a hand is put around the phone the signal strength bars fall dramatically.
This ignited a lot of debate about the relevance of signal strength bars.  Some suggested that the problem was caused by the algorithm displaying the bars and didn’t represent a real issue.  (Simon and I were asked to comment in two further articles about that on the WSJ website).  While some were blaming software people who had iPhone 4s were doing experiments, videos were recorded showing calls dropping.  Then the tech website Anandtech hacked into the software to enable a handset to report the signal strength in dBs.  This showed that the fall in signal strength was large: ~20dBm.
There are several possible reasons for this, even now it’s hard to be sure.
Many people have identified that touching the slot in the bottom left side of the handset causes the degradation.  That could have two underlying causes.  The antenna could be detuned by the dielectric material in the hand causing electric fields to change.  Or it could be that the RF current is being conducted from the antenna into the hand where it is dissipated by the hand’s resistance.  It could be a combination of both of these effects too.  Without careful measurement it’s difficult to tell this precisely.
A problem of this sort can only be completely solved by redesigning the antenna.  An antenna redesign can’t be done quickly or easily.  Apple decided to give iPhone buyers a free “bumper” case.  That case provides a spacing between the user’s hand and the sensitive parts of the antenna, it prevents conduction and reduces.  Some users have said that the problem still occurs with the bumper on, though it’s lessened.
This is a high profile example of a common sort of problem in handset design.  Though few handsets use radical new antenna designs many suffer from performance problems in particular usage scenarios.  For example, a sliding handset must work well with the sliding portion extended and retracted.  In both of those states it must work well in empty space, close to the head, and in the hand.  I’ve worked on many of these handset antenna problems before.  If they’re only found late in the project then they can be very difficult to solve.  Some projects over-run because of these problems, some switch the antenna type or antenna provider, and some have to be cancelled.
Hopefully the iPhone 4 antenna saga will encourage people to take antenna issues more seriously.  Perhaps in the future users will be slower to blame poor performance on the network operator and consider the possibility that their handset could be the problem.