Cell Range Expansion (CRE)

The intention of the Pico Cells is to offload traffic from the Macro cells to increase the system capacity. As a result, when Macro cell becomes overloaded, it would make sense to offload the MUE’s in the vicinity of the Pico cell to it. This can/should be done even if the UE is receiving a better signal from the Macro cell. The expansion of the range of the Pico cell is termed as CRE or Cell Range expansion.

To make sure that the UE does not fail in the handover process, the Time domain ICIC should be used and Macro cell should use ABS. The UE’s can be configured to do measurements on the Pico when the Macro is using ABS. The MUE now reports the Measurement reports to the Macro and are handed over to the Pico to act as PUE.

Myths and Challenges in Future Wireless Access

Interesting article from the recent IEEE Comsoc magazine. Table 1 on page 5 is an interesting comparison of how different players reach the magical '1000x' capacity increase. Even though Huawei shows 100x, which may be more realistic, the industry is sticking with the 1000x figure. 

Qualcomm is touting a similar 1000x figure as I showed in a post earlier here.

Interference Management in HetNets

Interference Management is a big topic in HetNet's. An earlier blog post here on similar topic was very popular. The above picture shows a Heterogeneous cellular network topology incorporating different forms of small cell deployments as an overlay on the macrocell network. Small cells would generally use secure tunnels back to the core network using existing broadband infrastructure. Whereas in the HCS (Hierarchical Cell Structures), different layers have different frequencies, thereby not causing radio frequency interference, in HetNets same frequencies can be used between different layers. The same frequencies can cause radio frequency Interference and necessitates the use of advanced Interference avoidance techniques.

CTTC has another interesting presentation on Interference Management in HetNets that I am embedding below as slides and video:

Interference Management in Co-Channel Femtocell Deployment from Zahid Ghadialy

The 'Phantom Cell' concept in LTE-B

One of the LTE-B proposals by NTT Docomo is this 'Phantom Cell' concept. A recent article from the IEEE Communications Magazine expands this further:


Phantom Cell Concept — In the current deployments, there are a number of capacity solutions for indoor environments such as WiFi, femtocells, and in-building cells using distributed antenna systems (DAS). However, there is a lack of capacity solutions for high-traffic outdoor environments that can also support good mobility and connectivity. Thus, we propose the concept of macro-assisted small cells, called the Phantom Cell, as a capacity solution that offers good mobility support while capitalizing on the existing LTE network. In the Phantom Cell concept, the C-plane/U-plane are split as shown in Fig. The C-plane of UE in small cells is provided by a macrocell in a lower frequency band, while for UE in macrocells both the C-plane and U-plane are provided by the serving macrocell in the same way as in the conventional system. On the other hand, the Uplane of UE in small cells is provided by a small cell using a higher frequency band. Hence, these macro-assisted small cells are called Phantom Cells as they are intended to transmit UE-specific signals only, and the radio resource control (RRC) connection procedures between the UE and the Phantom Cell, such as channel establishment and release, are managed by the macrocell.

The Phantom Cells are not conventional cells in the sense that they are not configured with cell specific signals and channels such as cell-ID-specific synchronization signals, cell-specific reference signals (CRS), and broadcast system information. Their visibility to the UE relies on macrocell signaling. The Phantom Cell concept comes with a range of benefits. One important benefit of macro assistance of small cells is that control signaling due to frequent handover between small cells and macrocells and among small cells can be significantly reduced, and connectivity can be maintained even when using small cells and higher frequency bands. In addition, by applying the new carrier type (NCT) that contains no or reduced legacy cell-specific signals, the Phantom Cell is able to provide further benefits such as efficient energy savings, lower interference and hence higher spectral efficiency, and reduction in cellplanning effort for dense small cell deployments.

To establish a network architecture that supports the C/U-plane split, and interworking between the macrocell and Phantom Cell is required. A straightforward solution to achieve this is to support Phantom Cells by using remote radio heads (RRHs) belonging to a single macro eNB. This approach can be referred to as intra-eNB carrier aggregation (CA) using RRHs. However, such a tight CA-based architecture has some drawbacks as it requires single-node operation with low-latency connections (e.g., optical fibers) between the macro and Phantom Cells. Therefore, more flexible network architectures should be investigated to allow for relaxed backhaul requirements between macro and Phantom Cells and to support a distributed node deployment with separated network nodes for each (i.e., inter-eNB CA).

LTE for Public Safety Networks

The last presentation on this topic couple of months back has reached nearly 7K views so here is another one from a recent article on the same topic from IEEE Communications Magazine

From M2M Communications to IoT

M2M was again in the news recently when a new report suggested that it would be $1 Trillion industry. Back in december I posted a detailed presentation on M2M that has now crossed over 6K views. This shows that there is an appetite for this topic. So here is a three part presentation on M2M and IoT. In fact as I pointed out in a post last year, it is very often referred to as IoE (Internet of Everything) rather than IoT (Internet of Things). If this is a topic close to your heart then please do come to the Future of Wireless International Conference (FWIC) organised by Cambridge Wireless on 1st and 2nd July 2013. Details here.

What is WebRTC and where does it fit with LTE and IMS

This simple video from MWC should give an idea on what WebRTC is and can do:


So what exactly WebRTC is in technical terms. Here is a recent presentation from WebRTC Conference and Expo

WebRTC Technical Overview and Introduction from Zahid Ghadialy

And here is another presentation that explains where it fits in with the LTE Architecture.

Extending 4G Communications with WebRTC IMS and WebRTC from Zahid Ghadialy

Dean Bubley from Disruptive Analysis has writted extensively on this topic and his recent post "Is the telephony "threat" from VoIP & WebRTC about competition or contextualisation?" is an interesting read.

Iain Sharp from Netovate recently pointed out that 3GPP have 'nearly' approved a work item for WebRTC access to IMS.

It would be interesting to see how operators will view WebRTC. As an opportunity or as a threat. Please feel free to air your opinions via comments.

DAS or 'Small Cells' and What is DAS anyway?

Its been a while I posted something on DAS (a.k.a. Distributed Antenna System). The articles I have posted have been mainly from AT&T and are here, here and here.

Picture source: The IET

Recently I read something interesting from IDG here:

According to Rob Bruce, Chief Operating Officer at distributed antenna system (DAS) vendor Axell Networks, a building is an asset, and that asset wants to deliver all the services it can in the simplest and most economical way.

"You wouldn't put five separate lighting systems into a building because there are five separate tenants in that building. You would put one in, and it becomes a utility for that building," Bruce told Techworld.

"Our view of life is it's the same for cellular coverage. You put one system in which covers the building. That is then a utility for the building, and operators can then connect into that infrastructure - that's how a DAS system works."

Bruce said that small cells are very good for single operator environments, when a single operator wants to add some capability into a particular area. But if they want to put multiple technologies into that environment then they have to put in multiple small cells.

So if a company in the UK wants to put GSM, UMTS and LTE into an office block, it has to install three small cells. If it wants to make that truly operator agnostic, it will probably have to put in 12 units, because each of the four operators uses at least three spectrum bands.

Axell Wireless recently installed a multi-operator DAS in The Shard in London, using 20 remote units to cover the whole building. Bruce claimed that, if the same thing had been done using small cells, it would involve over 100 units.

"So the building owner is saying I've got 100 lumps of intelligent electronics gadgetry that is scattered all over my building, and there's 4 different operators wanting access to all those different things in private flats, hotels and offices - it's just an operational nightmare," said Bruce.

Complete article is available here.

This is an interesting point because the Small Cells are still not evolved enough so that a single one can serve multiple operators, etc. Note that I am differentiating the closed residential femtocells from the public access small cells. Maybe a service such as FaaS or 'Femto as a Service' can help solve this problem. Based on my previous sentences, some of you may say that it should be called Small Cell as a Service (SCaaS) rather than FaaS but unfortunately that term has come to mean something else as can be seen here.

While initially the in-building solutions were mainly for coverage reasons, this may no longer be the only reason. Capacity is also an issue, especially in-building. Small cells can certainly help in the capacity area much more than DAS. Fortunately as most new phones are coming with inbuilt Wi-Fi chipsets and WiFi is available indoors in plenty, the capacity issue may no longer be a problem indoors. Again this is an area where we can have lots of discussions and each party with a vested interest can argue their case.

Here are couple of interesting videos from youtube that explain DAS:




There is also an interesting presentation by NEC in the Small Cell Americas event, embedded below:

Optimising Small Cells Architectures for In-Building Solutions from Zahid Ghadialy

802.11u, Passpoint and Hotspot 2.0 (HS 2.0)

Came across this interesting Video on Youtube explaining 802.11u that is embedded below.




A bit more detailed presentation on the same topic by Ruckus is also embedded below:


Related posts:

• Wi-Fi & Packet Core (EPC) Integration
• Hotspot 2.0, Next Generation Hotspot (NGH), etc.
• Cellular-Wi-Fi Integration - technology and standardization roadmap

Mobile Service status and Trends in the USA - 2012

This is an update to the presentation from 2011 that I blogged here.

Mobile Status and Trends in the US from Zahid Ghadialy

Technologies from Mobile World Congress 2013 (#MWC13)

If you liked the Gadgets roundup from yesterday then you would like this one as well:



You can read more about this topic here.



You can read more about this here.











You can read more about this here.


Finally:

Gadgets from Mobile World Congress 2013 (#MWC13)

Finally, if you have enough patience, here is Nokia keynote:



Related blog post:

• Dumbphones, Featurephones, Smartphones, Superphones...
• Videos from the CES 2013
• Future mobile technology with Graphene
• 5 videos showing futuristic technologies that can be used with Mobiles
• Mobile Device Testing and its Path to Commercialization

Wi-Fi & Packet Core (EPC) Integration

Yesterday I wrote a blog post on whether Wi-Fi is the third RAN in the Metrocells blog. Today I am posting this excellent presentation that details how this Wi-Fi integration with EPC will be done.

Wi-Fi & packet core integration from Zahid Ghadialy

LTE-A: Downlink Transmission Mode 9 (TM-9)

When LTE was introduced in Release-8 it had 7 transmission modes that were increased to 8 in Release-9. Earlier, I posted an R&S whitepaper on the different Transmission modes (10K+ views already) that listed transmission modes till TM 8. In Release-10 (LTE-A) 3GPP Introduced a new transmission mode, TM 9. TM9 is designed to help reduce interference between base stations to maximise signal stability and boost performance. The new TM-9 enables the enhancement of network capabilities and performance with minimum addition of overhead. TM9 is designed to combine the advantages of high spectrum efficiency (using higher order MIMO) and cell-edge data rates, coverage and interference management (using beamforming). Flexible and dynamic switching between single-user MIMO (SU-MIMO) and an enhanced version of multi-user MIMO (MU-MIMO) is also provided.

A new Downlink Control Information (DCI) format - known as format 2C - is used for TM9 data scheduling. Two new reference signals are defined in TM9: Channel State Information Reference Signal (CSI-RS) and Demodulation Reference Signal (DMRS). The first is used from the UE to calculate and report the CSI feedback (CQI/PMI/RI), while the latter is an evolution - providing support for more layers - of the UE specific reference signal that is already used for beamforming in Rel-9, and is used for signal demodulation. TM-9 is particularly smart as it can detect when a mobile device is being used and send a different type of signal that is optimal for a mobile device (variable DM-RS – demodulation reference signals). This maximises the efficient use of the base station and guarantee’s a decent data rate for users.

Early results in SK Telecom press release are positive with a claimed 10-15% increase in data rates in locations where there was known inter-cell interference.

I also looked into couple of books and here is one explanation from An Introduction to LTE by Chris Cox.

To use eight layer spatial multiplexing, the base station starts by configuring the mobile into a new transmission mode, mode 9. This supports both single user and multiple user MIMO, so the base station can quickly switch between the two techniques without the need to change transmission mode.

The base station schedules the mobile using a new DCI format, 2C. In the scheduling command, it specifies the number of layers that it will use for the data transmission, between one and eight. It does not have to specify the precoding matrix, because that is transparent to the mobile. The base station then transmits the PDSCH on antenna ports 7 to 7 + n, where n is the number of layers that the mobile is using. The maximum number of codewords is two, the same as in Release 8.

The mobile still has to feed back a precoding matrix indicator, which signals the discrepancy between the precoding that the base station is transparently providing and the precoding that the mobile would ideally like to use. Instead of using the PMI, however, the mobile feeds back two indices, i1 and i2. Both of these can vary from 0 to 15, which provides more finely-grained feedback than the PMI did and in turn improves the performance of the multiple user MIMO technique. The base station can then use these indices to reconstruct the requested precoding matrix.

Embedded below is an extract from Google books for Lte-Advanced Air Interface Technology By Xincheng Zhang, Xiaojin Zhou

Google Glasses - take two

Picture source: Guardian

So nearly after a year of my Google Glass post, looks like Google is ready to ship some of these glasses to some competition winners for $1500. Even the Facebook founder Mark Zuckerberg is excited and cant wait to get his hands on it.

There is also this new video showing 'How it Feels' wearing Glass and everytime I go back to youtube, the count increases by 100K. Embedded below:


My two main concerns are that I have to speak loudly to the glass which may not be convenient in public places or in front of others and the other being that when many people will have these devices, my Glass may pickup command from another user.

Sometime back there was a discussion on 'Bone conduction audio'. This will allow the user to hear from the Glass without the need of a headphone or speakers, I guess a similar kind of technology is needed in place of a mic. The Glass can sense that the user who is wearing it is talking instead of someone else. It should also solve the need to speak to speak loudly to the Glass.

Small cell standardization in 3GPP Release 12

A presentation looking at Small Cell Standardisation in 3GPP Rel-12.

Small cell standardization in 3GPP Release 12 from Zahid Ghadialy

Diameter, Signalling and LTE

Last year, I blogged about Signalling storm and Diamater here and here. Embedded below is a similar sort of presentation from the Fokus Fuseco Forum 2012.

What kind of signalling issues have to be solved by introducing LTE? from Zahid Ghadialy

M2M Standardization and its Role for Emerging Smart Cities

Interesting presentation from FOKUS Fuseco forum 2012.

Global M2M Standardization and its Role for Emerging Smart Cities from Zahid Ghadialy

Related presentation on slideshare here.

Scalable UMTS (S-UMTS) to accelerate GSM Refarming

Looks like a good idea from LTE will possibly be applied to UMTS/HSPA and it will also help accelerate the re-farming of GSM spectrum. A recent presentation from Qualcomm below:

Available to download from here.

Revisiting Coordinated Multi-point (CoMP) Technology

Looks like I re-visit CoMP every Q1 of the year. Couple of years back, I had posted a primer on CoMP here and last year I had a slide on schemes and deployments here. With Release-11 out of the door and  Release-12 getting in full swing in the standards, its time to re-visit this topic in a bit more detail. There are couple of presentations, one completely devoted to this topic and one that has a section on it. Both of them can be downloaded from slideshare.

CoMP and Interference Management Tech in 3GPP from Zahid Ghadialy

3GPP LTE Standards Update: Release 11, 12 and Beyond from Zahid Ghadialy

The story of Femtocells, Small Cells and Metrocells

Femtocells were introduced many years back as a residential, closed group, small base station. The intention was to provide coverage at home for high speed data (primary) and voice (secondary). It was more for coverage than capacity. In these good old days smart phones were far and few and feature phones were many. WiFi on the phone made it expensive and power hungry so cellular was the way to go.

There were many opportunities for Femtocells to take the centre stage as the concept is technologically sound but the operators have been not very willing to deploy it soon enough. Some operators were more willing to give it a try to fix their own issues, for example Softbank which gave free femtocells, in open access mode, to improve its coverage issues. Femtozone services that promised value addition provided with the Femtocells, never took off. Other promises of exclusive broadcast content using Femtocells for example never materialised due to lack of availability of the handsets and content.

Lot has changed since then. The smartphones and tablets have taken over the market, all of them have inbuilt WiFi that is generally more efficient than the cellular radio, coverage issues have become secondary and capacity issues are a bigger concern. Femtocell players have realised that except for the publicity, there isn't much to gain from the Femtocells. As a result Femtocells were replaced by the term Small cells that represents much more than the old Femtocells. The residential Femtocells have been reduced to being just voice boosters.

The different types of Small cells can be seen in the picture above. Except for the residential, the other types of small cells operate in either the open mode or the hybrid mode. Personally, I differentiate closed Femtocells from the other Small Cells. Metrocell is the upcoming type of Small cell that I believe everyone is focussing on. They operate always in the open mode and have been chosen as the promised one to solve the two major problems of capacity and coverage.

According to the Small Cell Forum introductory whitepaper, Metrocells would see an increased growth in the next few years when the operators start deploying more of them and less of the Macrocells.

So for those of you who don't know, and would like to learn more, an introductory presentation on Metrocells is available here.

If this is an area of interest and you are interested in having and in-depth understanding then we invite you to attend our Metrocells Masterclass which is a one day workshop explaining ins and outs of Metrocell. 

If you are a big organisation and would like us to provide you with a private workshop, please feel free to contact us for details.

We have also started the Metrocells Blog that I will use to post information related to Small Cells and Metrocells in future. Please feel free to take a look at: http://metrocells.blogspot.com/

Interference avoidance for in-device coexistence (IDC)

I posted on this topic couple of years back, so here is a quick update. There is also an article in IEEE Comsoc magazine if you can get hold of it.

Here is the updated 3GPP document

Study on signalling and procedure for interference avoidance for in-device coexistence from Zahid Ghadialy

Ten things Wi-Fi had in common with public toilets!

Interesting perspective from a presentation by Agilent in Cambridge Wireless Small Cells SIG.

Direct Communication in 3GPP Release-12

Here is a presentation from LG on this topic:

Direct Communication in 3GPP from Zahid Ghadialy

And a magazine article from IEEE on this topic:

Design Aspects of Network Assisted Device-to-Device Communications from Zahid Ghadialy

If interested in doing more research on this topic, also see this link.

Related posts:

• Public Safety Communications using LTE
• 3GPP Release-12 and beyond

Overview of 3GPP Release-12 Study Item UPCON

Mobile operators are seeing significant increases in user data traffic. For some operators, user data traffic has more than doubled annually for several years. Although the data capacity of networks has increased significantly, the observed increase in user traffic continues to outpace the growth in capacity. This is resulting in increased network congestion and in degraded user service experience. Reasons for this growth in traffic are the rapidly increasing use of smart phones and tablet like devices, and the proliferation of data applications that they support, as well as the use of USB modem dongles for laptops to provide mobile Internet access using 3GPP networks. As the penetration of these terminals increases worldwide and the interest in content-rich multi-media services (e.g. OTT video streaming services) rises, this trend of rapidly increasing data traffic is expected to continue and accelerate.

Here are couple of presentations on this topic:

Towards User-Plane Congestion Management in LTE EPS from Zahid Ghadialy

Overview of 3GPP Study Item UPCON from Zahid Ghadialy

Related blog posts:

• Data growth from 0.6EB/Mo to 10.6EB/Mo by 2016 (18x)
• Operators strategy for supporting the ‘Mobile Data Explosion’
• Data v/s Signalling Traffic in Dongles and Phones
• Capacity planning in mobile data networks experiencing exponential growth in demand
• 3GPP based 'Sponsored Data Connectivity'
• Downlink traffic distribution during 27 hours in one GGSN
• A Twitter discussion on 'Data Tsunami' myth
• Mobile Video is more than 50% of the data traffic

LTE-B, LTE-C, ... , LTE-X

Please make sure to read the comment from Kevin Flynn of 3GPP at the end

When I saw this picture above, I started wondering what LTE-B, etc. and started digging a bit deep. Came across this Ericsson presentation (embedded below) that shows the breakdown.

To just be sure that this is not Ericsson specific term, I also found a presentation by NTT Docomo (embedded below)

So I guess using LTE-B, LTE-C, etc. is better than saying 4.1G, 4.2G, etc. as we did in case of 3G/HSPA.


The presentations from Ericsson and NTT Docomo embedded below, available to download from Slideshare.

LTE evolution: Beyond lte-advanced from Zahid Ghadialy

Future Radio Access, M2M and Grand Societal Challenges from Zahid Ghadialy

LTE / EPC Signalling Training from eXplanoTech

Training is one of the areas we have been focussing on for a long time. Due to lack of bandwidth we have only been offering our training to a selected few customers but we are now expanding further. Here is a sample of LTE / EPS Signalling training

LTE / EPS Signalling Training from Zahid Ghadialy

Rel-11/12 3GPP Security Update

Here is the latest Security Update from 3GPP, presented in the 8th ETSI Security Workshop Jan 16-17 2013.

3GPP Security Update - Jan. 2013 from Zahid Ghadialy

All presentations are available from here to download.

Related blog posts:

• Quick update on 3GPP Release-12 progress
• The four C's of Release-12 enhancements
• Quick update on LTE Release 11 Work and Study Items
• 3GPP LTE Security Aspects
• Evolution of 3GPP Security
• 2 Presentations on Mobile technology Security

By the way, I will also be present in the Network Security conference in London in May 2013

Public Safety Communications using LTE

Public Safety Communications using LTE from Zahid Ghadialy

Videos from the CES 2013

Gorilla glass (above) is made by a company called Corning that is much more well known for its futuristic video, see here.











Finally, this Sony Xperia Z has got over 2 million hits, not exactly sure why so I have added the video for this as well

The four C's of Release-12 enhancements

Mid last year, I did a post on the LTE Rel-12 workshop and later another post on the progress.  Late last year, 3GPP posted a news item that the Rel-12 will be available by June 2014 and the main areas of focus will be as follows:

Exploiting new business opportunities

• Public Safety and Critical Communications 
  — Group Communications (GCSE_LTE)
• Proximity Services, including both Public Safety and Commercial aspects (ProSe)
• Machine Type Communications 
  — UE Power Consumption, Small Data and Device Triggering (MTCe_UEPCOP, MTCe_SDDTE )

WiFi integration

• Network Selection aspects (WLAN_NS)
• S2a Mobility with GTP for WLAN (FS_SaMOG)
• Optimized Offloading to WLAN in 3GPP-RAT mobility (FS_WORM)

System capacity and stability

• User plane congestion (UPCON)
• Core Network Overload (FS_CNO)

In addition to those three areas, other features can still be considered for completion in the Release 12 timeframe. The SA2 Working Group - responsible for Architecture - will produce time budgets to see whether further priority could be put on;

• Pure IMS features that can run in parallel with key items
• Policy and Charging Control for supporting fixed broadband access networks, PCC for fixed terminals (P4C BB1 and BB2)
• Application Based Charging (FS_ABC)
• User Monitoring Control Enhancements (FS_UMONC)
• LIPA Mobility and SIPTO at the Local Network (LIMONET)
• Operator Policies for IP Interface Selection (OPIIS)

Working Group SA2 will provide time budgeting information, for the selected features, at the next Plenary meeting - TSG#59, in March 2013.

Nokia Siemens Networks (NSN) has published their own whitepaper on 'LTE Release 12 and Beyond' (available on Slideshare here).

The following is their take on the four C's:


Release 12 enhancements focus on the four areas of Capacity, Coverage, Coordination (between cells), and Cost. Improvements in these areas are based on using several technology enablers: small cell enhancements, macro cell enhancements, New Carrier Type (NCT) and Machine-Type Communications (MTC). These enablers are described in this paper.

Customer experience, capacity and coverage will be improved with small cell enhancements, based on inter-site Carrier Aggregation, LTE-WLAN integration and macro cell enhancements. Small cell enhancements are also known as enhanced local access.

NCT helps achieve the required changes in the physical layer and initially provides base station energy savings, flexibility in deployment and ways to reduce interference in heterogeneous networks (HetNets).

Improvements in capacity and a more robust network performance are achieved by 3D Beamforming/MIMO (Multiple Input Multiple Output), advanced user equipment (UE) receivers and evolved Coordinated Multipoint (CoMP) techniques, as well as through Self-Organizing Networks for small cell deployments.

Finally, new spectrum footprint and new business will be opened up by optimizing the system for Machine-Type Communications, as well as by, for example, using LTE for public safety.


The whitepaper is available on Slideshare here.

VoLTE, Battery Issues and Solutions

Sometime back we had news about how VoLTE is battery killer and how it would suck our 4G phones dry. Well, I agree. I am no fan of VoLTE and think that CSFB solution can suffice in mid-term. Having said that, there is a solution which would be soon available to sort this battery issue during VoLTE call. I had a post on this topic earlier titled SPS and TTI Bundling. I am not sure about exactly how much saving would occur if either of the features are implemented.

ST Ericsson has recently released a whitepaper on this topic that is embedded below. If you have more idea on this, please add it in comments.

LTE, Telephony and Battery Life from Zahid Ghadialy

Dumbphones, Featurephones, Smartphones, Superphones...

Looks like there is still a lot of confusion in the different types of phones around so here is my take. Please feel free to correct me and I will update accordingly.

Dumb phones: The dumb phones were the original mobile phones whose intention was to allow voice and SMS initially and then later on some kind of data transfer using WAP.

Pic source: iPhaze

A typical dumbphone is as shown above. Dumb phones are no longer available but they can still be used if they are in the working order. Dumbphones were always pre-3G. It wouldnt make sense to have a 3G dumbphone but it is very much possible to have a 2G Featurephone/Smartphone.

Feature Phones: These came next. They allowed more stuff than the basic phones.

Pic source: Gadgetsteria

Featurephones (above) can do much more stuff, for example they may have camera to take photos, they may allow facebook to share the photos, they can have Skype to call, they can even have WiFi for access. Different people have different way of describing the difference between them and smartphones. Some distinguish Featurephones by suggesting that they have a closed operating system (OS) but this may not be necessarily true. Some others suggest that featurephones do not have touch screens while smartphones do, again this may no longer be considered true. There are featurephones available with basic touch functionality. I think an agreeable way to consider a phone a feature phone, in today's terms, can be based on a combination of processor speeds (less than 400MHz), screen size (less than 2inches), presence of physical buttons and pricepoint (less than $50).

Contrary to popular belief, featurephones are still popular and are going strong. See the chart below for example.

Pic source: Seeking Alpha

There is a good article that explains why Feature phone is 'Still the undisputed King' here to interested readers. The main reason according to me is that the reception is much better on Featurephones rather than Smartphones and they consume less battery power in general as compared to the smartphones.

Smartphones: Wikipedia suggests that the term smartphone was used as early as 1997 but what may have been considered as smartphone then is more like a featurephone of today. As per my knowledge, the first true modern smartphone were the Nokia communicators. If you look at the specs now, they may be classified as low end featurephones but they were the foundation for the smartphones.

Picture Source: Droid techy news

The first true modern smartphone that change the mobiles forever is undisputedly the original iPhone. On reflecting back, people had no idea what a phone could do until the arrival of the iPhone. This was soon followed by the iPhone clones and now we have many different ecosystems like Android, Bada, Windows mobile, Blackberry OS, etc. that gives its own flavour to the smartphones.

Superphones: The marketing industry is always thinking of using new terms to sell the products and while there has been terms like smarter-phones, super-smartphones, intelligent phones, etc. being thrown about, I think the industry has now converged on to use Superphones for the next generation devices. Some of the readers may be aware that 'Superphone' is used in Dr. Who series.

Again, there is no defined standards but looks like the superphone should have Quad core and its screen size should be more than 4.1inch. Samsung Galaxy S3 would qualify to be a superphone but its not referred to as one.

Phablets, Tabphones and Phonetabs: So what do you call a hybrid (or a cross between) Tablet and Smartphone? The answer could be any of the terms Phablets, Tabphones or Phonetabs. Again, there is no standard term but people have decided to use whichever term they feel like. Phablet is the most commonly used term.

Pic Source: CNet

Samsung Galaxy Note 2 is a good example of Phablet. One of the suggestions is that to qualify for Phablet, the screen size should be between 5 inches and 7 inches. Some of the users who have braved to buy one of the phablets, swear by it and in most cases vow to never go back to just a phone.

Picture Source: FT

FT has an interesting article that suggests the shipment of phablets could be around 200 million by 2015. It should be noted that according to me, WiFi only devices should not be considered as phablets as the phone part is missing. They are just mini-tablets. In case of 7 inch devices capable of phone and tablet functionality, it is a bit of a fuzzy area in cases where the user does not use the SIM card, thereby making the phone part unusable. For simplicity we can consider a device as phablet as long as the mobile functionality is embedded.

Energy-efficient femtocell implementation

In an earlier post, we saw an idea on how to have energy efficient Femtocell. Here is a practical implementation from ALU on energy efficient Femtocell.

Energy-efficient femtocell: Practical implementation from Zahid Ghadialy