Saturday 2 August 2008

LTE, IMS and Voice calls!

Picked this up from Martin's Blog. One of the things that has been left undefined are the end user applications. Unlike GSM and 3G+ where AMR RAB's has been defined for CS voice calls, there is no provision in LTE. In fact we know that CS domain is completely absent and only IP based PS domain is present. It has been assumed that IMS will be de-facto present along with LTE and the architecture rightly defines so but there is nothing stopping LTE being deployed without IMS. The following is from Martin's Blog:

LTE requires the IP Multimedia Subsystem (IMS) for voice calls. So what will happen to LTE if IMS doesn't take off? I know, many in the industry believe even asking such a question is close to heresy but who can promisse today that IMS will be a success?

The trouble with IMS and to some extent with mobile VoIP is not that it's a young technology, standardization has been going on for many years and books about it are going into their third edition. However, there are still no IMS systems out there today that have come out of the trial phase, and I have yet to see a mobile device with an IMS client which is nicely integrated and simply works. Also, the IMS standard is getting more complicated by the day which doesn't make life easier. Another main issue with VoIP and consequently IMS is power consumption. I use VoIP over Wifi a lot on my Nokia N95 and can nicely observe how the phone slightly heats up during a long phone call. Also the non-IMS but SIP compliant Nokia VoIP client in the phone, which by the way is nicely integrated, sends keep alive messages to the SIP server in the network several times a minute. This is necessary mainly due to Network Address Translation (NAT). While this doesn't require a lot of power over Wifi, power consumption skyrockets as soon as I configure VoIP for use over 3G. I can almost watch the power level of the battery drop as the network now constantly keeps a communication channel open to the device. So there are two problems here: VoIP calls cause a much higher processor load during a call, i.e. the VoIP talk time is much shorter than the 2G or 3G talk time and the standby time is significantly reduced. Add to that the missing handover capability to 2G and 3G networks (yes, I know there is VCC in theory) and you have a prefect package for a very bad user experience.

So the big question is if all of these things can be fixed, say over the next 5 years!? I have my doubts... If not, then LTE has a big problem. Will network operators accept running GSM or HSPA alongside LTE until the problems are fixed? The choice is this and accepting that LTE is for Internet access and some niche VoIP applications on devices such as notebooks or to decide sticking to HSPA(+) until things are fixed.

In case LTE is deployed and LTE - IMS devices are not ready it's likely that a device can't be attached to several radio networks simultaneously. So how do you inform a device attached to LTE about an incoming voice call? It looks like the people in standards bodies are looking at different solutions:
  • Send a paging message for an incoming circuit switched voice call via LTE to the device. You can do this on the IP layer or on the radio network signalling layer. The device them switches radio technologies and accepts the call.
  • Some people have started thinking about extending LTE with a circuit switching emulation.
This could be handled on the lower layers of the protocol stack and the software on top would not notice if the call uses GSM, UMTS or LTE. This one is easier said than done because I don't think this concept will fly without a seamless handover to a 2G or 3G network. If such a solution ever gets into mobile phones, it would make life for IMS even harder. Who would need it then?

Are there any other initiatives I have missed so far to fix the LTE voice issue?

Dean Bubley in his Disruptive Wireless Blog has interesting analysis on this topic as well:

My view is that operators should either work with Skype, Truphone, fring et al – or compete head-to-head with them using their own pre-standard mobile VoIP implementations. I still believe this is a good route to VoIPo3G, especially for operators that are already moving to VoIP in their fixed networks, or which are early deployers of IMS or other IP-NGN architectures. Blocking VoIP it not a viable option in competitive markets - as evidenced by the increasing trend towards openness that's been seen in recent weeks.

But interestingly, another ‘flavour’ of mobile VoIPo3G is now emerging as an alternative for mobile operators – Circuit Switched Voice over HSPA, as an early specification within 3GPP’s Release 8 generation of standards. This was just starting to evolve seriously when I published the report in November, and is mentioned in the comments on this post of mine. And it now seems to be moving fast. In the last week, two of the largest ‘'movers and shakers' in mobile technology - from both handset and network sides - have talked up this approach to me unprompted. And I’m in agreement that it’s undoubtedly going to be important.

Basically, CS voice over HSPA takes the ordinary mobile circuit voice service, using ordinary diallers on the phone, and circuit core switches in the network... and tunnels it over an underlying IP bearer. So the application isn't VoIP, but ordinary circuit telephony, but the wireless transport (down in the guts of the phone) is IP.

In other words, it's "Mobile Circuit Telephony over IP"

In fact, we've all heard this concept before. It is an almost direct HSPA equivalent of UMA’s voice over WiFi. In both cases, there are benefits for operator voice calls, derived from the nature of the radio IP bearer: cost in WiFi’s case as it’s unlicenced spectrum, and the efficiencies of new packet transmission techniques in HSUPA and beyond. And in both cases, it’s not necessary for the operator to have already deployed IMS, VCC and so forth – they can reuse their existing core networks, and get away with less messing-around at the handset application layer. [I’m not sure yet whether the IP tunnel uses a similar IPsec approach to UMA, and could use a similar gateway, or if it’s entirely new]. The downside is that this isn’t a next-gen IP voice service in terms of application capability – it’s voice 1.0 transported over network 3.5.

There are also various reasons why I'm more positive on CS over HSPA than I am about WiFi-UMA.

It's a matter of semantics whether you treat CS Voice over HSPA and UMA as 'true' wireless VoIP. Both are using classic circuit signalling, rather than SIP or proprietary protocols like Skype. Neither are as easy to use as "full VoIP" as the basis of innovative applications like voice mashups.

The interesting thing to me is that the industry is starting to polarise into different points of view on this issue. Ericsson remains a staunch MMTel advocate, driven by its desire to push IMS as the main future application layer. But other major players seem to be edging towards a CS over HS worldview, albeit with a hedge around naked-SIP VoIP.

So… taken together, the various types of VoIPo3G are going to be:
  • Over-the-top independent VoIP (Skype, Truphone, IP-PBX etc) with a dedicated client on the handset or PC
  • CS voice over HSPA, using the ordinary circuit voice app plus some lower-level IP ‘plumbing’.
  • IMS MMTel – needing a full IMS client on the device
  • Other IMS or standards-based voice apps like PoC or perhaps a standalone SIP VoIP server plugged into the IMS application layer
  • Standalone operator softswitch-based VoIP connecting to a (probably) SIP client on the handset.
  • Partnerships or mashups of the above.

Messy and diverse, in other words. And all of these have different use cases, different pro’s and con’s, different requirements in terms of user behaviour, cost and so on.

But the bottom line is that with the addition of CS Voice over HSPA, my top-level VoIPo3G predictions are still looking feasible, although some of the fancier web- or application-based VoIP capabilities will be trickier to exploit by the operators choosing that approach.

I have to admit that I havent looked into this area at all and cannot comment on which direction things will move. One thing that I can definitely say from my experience is that the initial movers, if successful, will set the direction for others to follow and may be eventual winners.

Keep fit with 'Run Keeper'

A new application on iPhone helps keep fit without worrying about keeping track of the minute details. Run Keeper, centers on a really simple tracker that follows your location as you run via GPS, then puts that information into a personal database.

Every time you complete a run you can see how far you went (to the best of the phone's tracking capabilities), along with the time spent and how it compares with previous runs, all on a Google Map.

Developer Jason Jacobs of FitnessKeeper tells us it's just the tip of the iceberg for planned development and that much bigger things are on the way. For people too cheap to shell out for Nike's iPod nano-centric run tracker this makes a viable alternative albeit with less integration with iTunes. Nice, however, is the option to check out your data from any computer since the maps and runs are stored in the cloud.

While Jacobs has designed the application for tracking runs, another viable use for this is tracking trips in vehicles. Businesses looking to keep an eye on their employees' short-haul trips could use such a system to make sure they're going where they said they did.



The following Video on youtube has demonstration:




Friday 1 August 2008

New urgency on LTE Femtocells

Equipment vendors' focus on finalizing Long-Term Evolution (LTE)/Systems Architecture Evolution (SAE) standards specifications by the end of 2008 has raised concerns that femtocell standards work, which also faces a tight deadline, could suffer as a result.

Both LTE/SAE and femtocells -- or, Home Node Bs in 3rd Generation Partnership Project (3GPP) terminology -- have a deadline of around December this year for their specifications to be included in the next 3GPP release, Release 8. It's a critical target for both technologies.
Given the weight of influence behind LTE/SAE, not everyone is convinced that femtocells will meet that December cutoff. Despite the greater focus on so-called 4G technology LTE, other industry sources close to the standardization process believe the femto specs will be developed enough to be included in the initial Release 8 draft, even if they're not completed.


Any changes required after the "freeze" date, scheduled for December, would be done in a controlled way. But it's possible that not all of the functionality will be included as originally intended, and that some planned specifications work would need to be deferred to the next standards release, due one year later. Some femtocell executives aren't concerned that some details might miss this year's deadline, as the specs work in question isn't vital for initial home base station deployments.

But a lot is at stake for femtocells. Operators stress the need for standardized femto equipment, or at least a clear view of how vendors will support a standard in their equipment, before they can even consider large-scale deployments. A holdup in the standards would delay this new home base station market.

It's not hard to see how infrastructure suppliers would struggle to meet all the standardization demands for these two technology groups and how their resources could be stretched at the 3GPP. The next 3GPP release is chock full of other important technologies, in addition to femtos and LTE, such as those related to HSPA evolution and mobile IP core. On one hand there is LTE/SAE, an entirely new radio access technology, and mobile core, which has some of the world's biggest operators backing it as their so-called 4G next-generation infrastructures, with some carriers, such as Verizon Wireless , Vodafone Group plc, China Mobile Communications Corp. , and NTT DoCoMo Inc., already talking about commercial deployments. On the other hand, those same influential carriers are eager to put femtocell technology in their networks to see if the home base stations can live up to the promises of providing cost savings, capacity increases, churn reduction, and future new revenues, all without provisioning problems and economic subsidies.

The next plenary meeting of the Femto Forum Ltd. in September in Bangkok will be crucial for vendors to reach a consensus on some of the details in the Home Node B standard. Progress has already been made with the agreement on the Iu-h protocol for the link between the femto access point and femto gateway.

PicoChip has already announced earlier the availability of the industry’s first LTE femtocell and picocell reference designs, the PC8608 Home eNodeB and PC8618 eNodeB respectively. Now, Agilent announced that engineers from Agilent, picoChip and mimoOn have successfully tested a 3GPP LTE femtocell reference design using Agilent's MXA signal analyzer VSA test solutions.

The three companies have collaborated to ensure that the tests of their reference design meet the requirements of the LTE standard in development. Their engineering cooperation has advanced the technology needed to meet the demands of the emerging LTE femtocell market.

The test solutions used to validate the femtocell reference design included an Agilent MXA Signal Analyzer with the Agilent 89600 Series Vector Signal Analysis (VSA) software and its new 3GPP LTE modulation analysis option. This recently introduced option provides RF and baseband engineers working on early LTE devices with the industry's most comprehensive signal analysis solution for physical layer testing and troubleshooting. The Agilent 3GPP LTE VSA option enables LTE signal analysis from the analog or digital baseband through to the RF antenna for Node B infrastructure as well as end-user equipment prototype designs.

Currently, none of the parties involved in trialling Femtocells are interested in standardisations as they want to be the first in their pioneering approach. The standardisation activity may be a long way to go but their implementation may be longer way away.

Sunday 27 July 2008

Adaptive Antenna System

Whenever we talk about the evolution of new technology in telecoms world one thing which always occupy the prominent position is the spectral efficiency. The success and efficiency of any wireless system depends on the spectral efficiency.

What is spectral efficiency though?

Spectral efficiency can be defined as bits/seconds/Hz/cell. It measures how well a wireless network utilizes radio spectrum and also determines the total throughput each base station (cell) can support in a network in a given amount of spectrum.

There is no doubt that if a new air interface is to be build it should be built from the ground up to be optimized for spatial processing. Spectral efficiency directly affects an operator’s cost structure. For a given service and grade of service, it determines the following:
  • Required amount of spectrum (CapEx),
  • Required number of base stations (CapEx, OpEx),
  • Required number of sites and associated site maintenance (OpEx), and,
  • Ultimately, consumer pricing and affordability

Spectral efficiency will become even more important as subscriber penetration increases, per-user data rates increase and the as quality of service (esp. data) requirements increase.

There are so many elements for design to achieve high spectral efficiency. Adaptive Antenna System (AAS) is one of the methods to achieve high spectral efficiency.

Adaptive Antenna System (AAS) provides gain and interference mitigation leading to improved signal quality and spectral efficiency.

The use of adaptive antenna systems enables the network operators to increase the wireless network capacity, where such networks are expected to experience an enormous increase in the traffic. This is due to the increased number of users as well as the high data rate service and applications. In addition, adaptive antenna systems offer the potential of increased spectrum efficiency, extended range of coverage and higher rate of frequency reuse.

Adaptive antenna systems consist of multiple antenna elements at the transmitting and/or receiving side of the communication link, whose signals are processed adaptively in order to exploit the spatial dimension of the mobile radio channel. Depending on whether the processing is performed at the transmitter, receiver, or both ends of the communication link, the adaptive antenna technique is defined as multiple-input single-output (MISO), single-input multiple-output (SIMO), or multiple-input multiple-output (MIMO).

Multipath propagation, defined as the creation of multipath signal paths between the transmitter and the receiver due to the reflection of the transmitted signal by physical obstacles, is one of the major problems of mobile communications. It is well known that the delay spread and resulting inter symbol interference (ISI) due to multiple signal paths arriving at the receiver at different times have a critical impact on communication link quality. On the other hand, co-channel interference is the major limiting factor on the capacity of wireless communication systems, resulting from the reuse of the available network resources (e.g., frequency and time) by a number of users.

Adaptive antenna systems can improve link quality by combining the effects of multipath propagation or constructively exploiting the different data streams from different antennas. More specifically, the benefits of adaptive antennas can be summarized as follows:

  • Increased range/coverage: the array or beam forming gain is the average increase in signal power at the receiver due to a coherent combination of the signal received at all antenna elements. The adaptive antenna gain compared to a single element antenna can be increased by an amount equal to the number of array elements, e.g., an eight element array can provide a gain of eight (9 dB).
  • Increased Capacity: One of the main reasons of the growing interest of adaptive antennas is the capacity increase. In densely populated areas, mobile systems are normally interference-limited; meaning that interference from other users is the main source of noise in the system. This means that the signal to interference ratio (SIR) is much larger than the signal to thermal noise ratio (SNR). Adaptive antennas will on average, increase the SIR. Experimental results report up to 10 dB increase in average SIR in urban areas. For UMTS networks, a fivefold capacity gain has been reported for CDMA.
  • Lower power requirements and/or cost reduction: Optimizing transmission toward the wanted user achieves lower power consumption and amplifier costs.
  • Improved link quality/reliability: Diversity gain is obtained by receiving independent replicas of the signal through independently fading signal components. Based on the fact that one or more of these signal components will not be in a deep fade, the availability of multiple independent dimensions reduces the effective fluctuations of the signal.
  • Increased spectral efficiency: Spectral efficiency is a measure of the amount of information –billable services- that carried by the wireless system per unit of spectrum. It is measured in bits/second/Hertz/cell, thus it includes the effect of multiple access methods, modulation methods, channel organization and resource reuse (e.g., code, timeslot, carrier). Spectral efficiency plays an important role since it directly affects the operator cost structure. Moreover, for a given service and QoS, it determines the required amount of spectrum, the required number of base stations, the required number of sites –and associated site maintenance-, and ultimately, consumer pricing and affordability. Equation (1) shows a simplified formula to estimate the required number of cells per square kilometer. (the offered load is in bits/seconds/km2).
  • Security: It is more difficult to tap a connation, since the intruder has to be position himself in the same direction of arrival as the user.
  • Reduction of handoff: there is no need for splitting the cells for the sake of capacity increase, and in consequence less amount of handoff.
  • Spatial information: the spatial information about the user would be available at any given time, which enables the introduction of Location Based Services.

In addition to the above-mentioned benefits and liken any other systems AAS has got it’s own drawbacks as well. One must point out the following drawbacks (or costs) of the adaptive antennas:

  • Transceiver Complexity: It is obvious that the adaptive antenna transceiver is much more complex than the conventional one. This comes from the fact that the adaptive antenna transceiver will need separate transceiver chains for each of the array elements and accurate real-time calibration of each of them.
  • Resource Management: Adaptive antennas are mainly a radio technology, but they will also put new demands on network functions such as resource and mobility management. When a new connection is to be set up or the existing connection is to be handed over to a new base station, no angular information is available to the new base station and some means to “find” the mobile station is necessary.
  • Physical Size: For the adaptive antenna to obtain a reasonable gain, an array antenna with several elements is necessary. Typically arrays are consisting of six to ten horizontally separated elements have been suggested for outdoor mobile environments. The necessary element spacing is 0.4-0.5 wavelengths. This means that an eight-element antenna would be approximately 1.2 meters wide at 900 MHz and 60 cm at 2 GHz. With a growing public demand for less visible base stations, this size, although not excessive, could provide a problem.

An Adaptive Antenna System (AAS) can focus its transmit energy to the direction of a receiver. While receiving, it can focus to the direction of the transmitting device. The technique used in AAS is known as beamforming or beamsteering or beamshaping. It works by adjusting the width and the angle of the antenna radiation pattern (a.k.a. the beam). Combined with multiple antennas in the Base Station (BS), AAS can be used to serve multiple Subscriber Stations (SSs) with higher throughput. A technique known as SDMA (Space Division Multiple Access) is employed here where multiple SSs that are separated (in space) can transmit and receive at the same time over the same sub-channel.

AAS also eliminates interference to and from other SSs and other sources by steering the nulls to the direction of interferers.AAS is feature suits very well for LTE and it is an optional feature in WiMAX as it yet to be included in WiMAX certification. But due to its effectiveness in improving performance and coverage especially in Mobile WiMAX case, many vendors integrate AAS capability into their products.

Saturday 26 July 2008

USSD: Old is Gold

Even though there are so many new technologies available for creating mobile applications, there is still a market for the old fashioned USSD applications.

USSD or Unstructured Supplementary Service Data is a capability of all GSM phones. It is generally associated with real-time or instant messaging type phone services. There is no store-and-forward capability that is typical of 'normal' short messages (in other words, an SMSC is not present in the processing path). Response times for interactive USSD-based services are generally quicker than those used for SMS.

A sample USSD service is the bill status service accessed by dialing *141# or similar numbers in between * and #. USSD applications can be thought of as an IVRS (Interactive Voice Response System) with out voice.

Some of the USSD applications that we use regularly are:
  • Alerts About special offers, services and news
  • Balance enquiry
  • Changing tariff plan and subscribing to various VAS services.
  • Recharging using prepaid vouchers

Other than these many interesting services can be given using the USSD platform. One such service is the “call back” service. The user will use USSD to send a USSD message to his friend asking him to call back. This is done by pressing the USSD service number and the number to which the alert needs to be send. Assume 14 is the service number and you want me to call you back. Press this on your mobile and press dial.

*14*9846831128#

I will receive a message, “XXXXXXXXXX wants you to call him back” where XXXXXXXXXX will be your number.

Barclays has started a Hello Money service in India. This is a USSD based service and quick demo can be viewed here.

A similar service is being tested in Kenya called Commerce 360. Commerce 360 will link banks, utility services and other companies with the mobile phone owners. Other than Kenya, Cellulant which is one and half year old has subsidiaries in Uganda, Tanzania and Nigeria in which it intends take the Commerce 360 mobile banking solution if it succeeds in the Kenyan market.

Finally if interested here is a youtube video from late early 2000's showing USSD in practice.


Friday 25 July 2008

Spying: Bluetooth style

According to a security expert, writing in Cnet:

Bluetooth headset users are at risk because of a security hole in the technology and default PINs that don't get changed, he said. Exploiting vulnerabilities someone can break in and steal data from the phones, make calls without the cell phone owner knowing, listen in on and break into conversations, and even spy on people by turning the device into a bug. He advises that people change the default password, disable the Bluetooth on the phones, turn off the headsets when not in use, and limit access to the data and features when communicating with other Bluetooth devices.

There may be more reasons to switch Bluetooth off.

According to an article in Guardian:

Tens of thousands of Britons are being covertly tracked without their consent in a technology experiment which has installed scanners at secret locations in offices, campuses, streets and pubs to pinpoint people's whereabouts.

The scanners, the first 10 of which were installed in Bath three years ago, are capturing Bluetooth radio signals transmitted from devices such as mobile phones, laptops and digital cameras, and using the data to follow unwitting targets without their permission.

The data is being used in a project called Cityware to study how people move around cities. But pedestrians are not being told that the devices they carry around in their pockets and handbags could be providing a permanent record of their journeys, which is then stored on a central database.

The Bath University researchers behind the project claim their scanners do not have access to the identity of the people tracked.

Although initially confined to Bath, Cityware has spread across the planet after the software was made freely available on the internet sites Facebook and Second Life. Thousands of people downloaded the software to equip their home and office computers with Cityware scanners.

More than 1,000 scanners across the world at any time detect passing Bluetooth signals and send the data to Cityware's central database. Those with access to the database admit they do not know precisely how many scanners have been created, but there are known to be scanners in San Diego, Hong Kong, Australia, Singapore, Toronto and Berlin.

In Bath alone scanners are tracking as many as 3,000 Bluetooth devices every weekend. One recent study used the scanners to monitor the movements of 10,000 people in the city.
About 250,000 owners of Bluetooth devices, mostly mobile phones, have been spotted by Cityware scanners worldwide.

Bluetooth tracking technology is already being used to aim advertisements at people, for example as they walk past shops or billboards.

Bluetoothtracking.org, a website based in the Netherlands, is using the same technology to publish live data about people's movements across the town of Apeldoorn. The facility allows people to search the whereabouts of friends and associates without them knowing about it.

Some scientists using the technology describe a future scenario in which homes and cars adapt services to suit their owners, automatically dimming lights, preparing food and selecting preferred television channels.

I like Bluetooth as it makes my life convinient and also because one of our initial projects has been developing of complete Bluetooth marketing solution for a media company. So yes, maybe the next time you go to a shopping mall and get some advertised pumped on your handset using bluetooth then you can blame my company.

Ps: There is another article on Guardian by Dr Vassilis Kostakos from Bath University, defending his team. See here.

Monday 21 July 2008

SDWN: Beyond Femtocells

Missed this one earlier from Fierce Broadband Wireless:

Femtocells have little ability to become self-organized or perform network management functions. WiMAX and LTE, on the other hand, are based on highly adaptive OFDMA air interfaces and IP communications that enable architecting of self-configured and distributed networks. They become part of the broader unified communications industry movement toward smart, distributed networking that is augmented by distributed storage and application servers. The largest opportunities for WiMAX are Smart Distributed WBB Networks, SDWN, and Purpose Use of Multiple Spectrum bands (PUMS).

The SDWN wireless interface layer is based on scalable OFDMA, adaptive modulation and power control methods that enable the network to adapt to a variety of channel bandwidths, range, multi-path environments, and attenuating signal conditions and usage.

The same factors that are now driving intelligent wired networks are amplified by the nature of wireless: limited available spectrum. MIMO- beam forming, smart antenna and smart power regulation built into remote and mobile stations can achieve very high localized performance while working as an adaptive layer within the managed network.

The term ‘WiMAXmesh' is used by some companies to describe SDWN functionality for multi-hop relay network capabilities now being implemented into WiMAX integrated circuits and network devices. Currently, WiMAXmesh can include on-board or local memory and storage, support for multiple external network interfaces and optimized network routing capabilities.

SDWN is highly motivated by the need to deliver cost effective networks able to respond to high bandwidth demands from both enterprise and consumer markets. The need to be integrated as part of enterprise level networks compels development of self-configuring, self-organizing WBB networks. The growing demand for personal broadband, including social networking and video media, will propel the pace of SDWN developments.

We believe that SDWN will develop over the next 10 years to become two to four times larger than the conventional centralized wireless broadband network market.

Key stake holders in SDWN development include most major companies involved in WiMAX and 3G-LTE including:

  • Alcatel-Lucent: A leading developer of co-MIMO, MU-MIMO technologies
  • Alvarion: An early implementer of distributed network capabilities
  • Cisco: We think that Cisco intends to become the leader in SDWN for both WiMAX and LTE. Products may not appear for up to two years.
  • Intel: Offers distributed processor architectures and enabling IP.
  • Nortel: An early leader in MIMO-OFDM and is continuing development toward SDWN
  • Motorola: The company is not as visible but has developed corresponding IP
  • Ericsson: Has recently entered submittals to 802.16 that correspond to work in LTE.
  • Huawei: A rising developer in SDWN technologies.
  • Numerous efforts are underway among WiMAX, LTE and multi-mode chip and smaller equipment suppliers. picoChip and DesignArt are noticeable examples.

Keywords:

  • WBB - Wireless Broadband
  • WBBN - WBB Networks
  • SDWN - Smart Distributed WBB Networks
  • PUMS - Purpose Use of Multiple Spectrum bands

Sunday 20 July 2008

We are becoming a bunch of 'Techno Time-wasters'

This one is in todays Observer:

Time-wasting is not just an irritating habit. It is an affliction that ruins millions of lives and often requires therapy and other treatment for sufferers, psychologists have warned. According to new research, one person in five now suffers from the problem so badly that their careers, relationships and health are threatened. Many researchers blame computers and mobile phones for providing too many distractions for people.

'The subject is seen as joke,' said Professor Joseph Ferrari of DePaul University in Chicago. 'But the social and economic implications are huge. These people need therapy. They need to change the way they act and think.' Ferrari says that chronic procrastination is now so serious a condition it needs to be recognised by clinicians. In a study to be published later this year, he estimates that 15 to 20 per cent of people are chronic procrastinators
He has devised a questionnaire to help diagnose the condition, which he says is 'much more common than depression or common phobias'. Procrastination also has knock-on effects - it encourages depression, lowers self-esteem, causes insomnia, and indirectly affects health by discouraging visits to the dentist or doctor. Sufferers are also more likely to have accidents at home involving unmended appliances.

Cognitive psychologist Professor John Maule, of Leeds University's business school, agreed that a significant proportion of the population were prone to procrastination, and argued that mood changes - particularly depression - might be to blame.

Research by Professor Piers Steel from Calgary University indicates that the incidence of chronic procrastination has risen dramatically in recent decades, from one person in 20 to one in four, as new technology has come to dominate our lives. Even the beeps notifying the arrival of email are said to be causing a 0.5 per cent drop in gross domestic product in the United States, costing the economy $70bn a year.

Ferrari, however, is less convinced that new technology is to blame for time-wasting. 'People have wasted time for centuries,' he said. 'Lots of people, particularly people who often have to work under time constraints, put work off because they kid themselves that they work best when under pressure, when there's a deadline.

'Studies have shown this isn't true. They're conveniently forgetting the times when it all went horribly wrong - and selectively remembering the odd occasion when things went well under severe time pressure.'

Once, humans probably did have stronger excuses for delaying chores that didn't need immediate attention, say brain scientists such as Alan Sanfey at Arizona University, whose work has shed light on the evolutionary origins of procrastination.

It appears that the brain is divided into two parts. One triggers 'automatic responses' which take precedence over everything else - such as fleeing sabre-toothed tigers. The other governs 'deliberate responses' - writing that report due next week or booking a visit to the optician. Evolution has dictated that the former take precedence. Today there aren't any sabre-toothed tigers, but we still put things off.

Saturday 19 July 2008

LTE and WiMax Harmonization

Everytime I decide to move away with the LTE and WiMax subject I just find something new to tell you guys. Recently I have found that some more debate is emerging from the LTE and WiMax camps regarding the harmonization between them.
As I said from the very beginning, in my opinion the harmonization of WiMAX and LTE makes good sense for the development of the industry. There is enough evidence that the two camps are interestedand participants from both the WiMAX and LTE camp and IEEE and ETSI 3GPP standards organizations have recognized the need to collaborate on development of communications.
You might remember from my previous blogs that outgoing CEO of Vodafone, Arun Sarin was one of the first to raise the issue openly of the two camps having a future together. Vodafone is among operators that have called for the merging of WiMAX and LTE because this will reduce conflicts and costs for the industry. The long-term trends in technology, regulation, ecosystem consolidation and globalization contribute to the rationale that wireless systems should strive to achieve common air interfaces where feasible. The primary obstacle to achieving harmonization of WiMAX and LTE is simply the commercial self-interests that prevent a common push forward.
Intel CEO Paul Otellini and Sean Maloney, head of Intel's sales and marketing, have called for harmonization between WiMAX and LTE, pointing out the goals of unified broadband communications and common use of technologies. But everything which is coming out of Intel in terms of two technologies, it clearly suggests that Intel will eventually provide combined support regardless of whether the standards groups achieve official harmonization or not. I am sure that Intel will provide a multi-mode WiMAX plus LTE chipset. Maloney came close to saying this but he preferred to say this
"We don't have any plans to do that yet; it would certainly be a nice long term goal."
I have no doubt that harmonization has become a hot topic because of heightened competition between WiMAX and LTE for a role in molding development of the next generation of wireless, 4G. While I do not think the current stage of development of WiMAX or LTE qualifies as 4G, both systems are frameworks for evolution to 4G.
There are several factors within wireless developments to compel harmonization. Following are some of them
-Pursuit of IMT-Advanced as the path to 4G
-Both existing 3G, ‘fixed' and new spectrum will be consolidated
-Multiple scale and application support
-Common SDR (Software Defined Radio) base stations
-Common Integrated Circuits
-Use of 80 percent to 90 percent common technologies
-Globalization of R&D
-Need for reduced cost for embedded applications & digital divide
-Harmonization of wireless standards is a stated goal of 3GPP
-Common ‘modular concept' for harmonization across systems

If we take a ‘30,000 foot perspective' at the evolution of communications, it becomes clear that arriving at common air interfaces is now not only feasible but also a desirable result. Leading wireless suppliers have consolidated in order to leverage content, services and applications across networks. Technology used in WiMAX and LTE are converging because both camps have come to similar conclusions on the technologies needed to form the next-generation evolutionary framework. In brief, the framework includes OFDMA, MIMO and Adaptive Antenna Systems (AAS) smart antenna technologies, and IP-based adaptive network architecture. The few significant differences between WiMAX and LTE are surmountable and can fit within the capabilities of increasingly adaptive radio techniques and smart IP-based network developments.
Further, societal demands for digital inclusion, a growing need for education, enterprise and government communications, harnessing of communications as an alternative to travel, and better use of spectrum resources compels a unified approach to wireless.
While all these talks of harmonization continue there are still some in the industry who favors one over another. This was evident when recently Sprint announced that it’s withdrawing from the Next Generation Mobile Networks (NGMN) Alliance, a group of global mobile operators that banded together last year to push for a common vision for networks and technologies beyond 3G. The operator was a founding member of the NGMN. Sprint said it ended its relationship with the NGMN Alliance after the group chose to endorse LTE (Long Term Evolution) for 4G. Sprint spokesman John Polivka said the NGMN was supposed to endorse the co-existence of various technologies without favoring one over another. In fact, he said, technology neutrality was a key tenet of the NGMN to make sure it didn't duplicate the work being done in existing standards bodies.
"Sprint was disappointed that NGMN shifted from its original technology-neutral stance. We respectfully withdrew our membership from the organization due to the change in direction," he said. "We are enthusiastically continuing with our plans to work with our burgeoning ecosystem and launch a WiMAX network in select U.S. cities beginning in the third quarter with expansion throughout 2009 and beyond."
Founding members of the NGMN Alliance include China Mobile, NTT DoCoMo, Vodafone, Orange, KPN and T-Mobile, all of whom back LTE. A quick look at the list of the 18 operator members on the NGMN Alliance website shows the majority of the operators come from the WCDMA community, whose 4G path is LTE.
Another evidence of favoring one over the other occurred when in-flight communications provider Aircell announced that the future of its mobile broadband network will be based on LTE (Long Term Evolution).
Today, the company's Gogo service uses CDMA 1xEV-DO Rev. A technology, which enables the company to offer its air-to-ground data service at a data rate of more than 12 Mbps peak to Gogo-equipped aircraft. By the end of 2009, further advances to EV-DO will enable Aircell to deliver a raw data rate of up to 22.7 Mbps to aircraft. And by the start of 2011, Aircell expects to deploy its 4G LTE network, which will enable a throughput of up to 300 Mbps to aircraft.
The company says LTE will enable in-flight services such as hi-definition and interactive television as well as multi-player gaming. Aircell said it also chose LTE as a way to future-proof its air-to-ground technology. Airlines will also benefit from LTE because the technology will allow them to enhance their operations by offering applications such as high-resolution weather to the cockpit, the company said.
The company's customers so far include Virgin America and American Airlines

Ron Resnick, president of the WiMAX Forum, has said that the harmonization between WiMAX and LTE is "really up to the operators if that's what they want to do." That is the deciding factor that will determine to what extent WiMAX and LTE harmonize within the standards groups. Make no mistake, the technologies, ICs, devices, and systems are in the process of converging. Whether this occurs harmoniously or with excess rancor is up to the industry.

Thursday 17 July 2008

HSUPA is here

T-Mobile recently launched HSUPA network here in UK:

T-Mobile said, in certain areas, upload speeds will be five times faster than previously. It claims upload speeds of up to 1.4 Mbps. T-Mobile UK chief executive Jim Hyde said: "Mobile broadband has come of age. Today, 25 per cent of new contract customers are signing up and we expect to quadruple our user base in 2008.

"We knew mobile broadband would burst on to the scene and our continued investment in new technology is paying dividends for customers seeking a fast, consistent service which offers great value."

T-Mobile has also upgraded its HSDPA network, it said. It now boasts download speeds of up to 7.2Mbps within the M25.

Meanwhile, T-Mobile Germany has annoucned the completion of the HSPA upgrade to it's 3G network, meaning that customers can now download (HSDPA) at 7.2Mbps. The plan is that the upload speed (HSUPA) will be boosted to 2Mbps by the end of the year.

In other news, AT&T in USA plans for 2008 include the completion of the nation's first High Speed Uplink Packet Access (HSUPA)-enabled network by the middle of the year. The AT&T 3G network now delivers typical downlink speeds ranging between 700 Kbps (kilobits per second) and 1.7 Mbps (megabits per second), and it will now offer faster uplink speeds ranging between 500 Kbps and 1.2 Mbps. The faster uplink speeds allow AT&T's HSUPA-enabled laptop users to quickly send large files and take full advantage of the latest Internet and business applications.

An article in TelecomTV claims that Mobile Social Networking may be the killer application for the promised HSUPA:

This is the year for HSUPA, or High-Speed Uplink Packet Access, according to leading provider of the enabling technology, Qualcomm. HSUPA is the companion standard to HSDPA (the high speed downlink standard) and enables 3G users to upload large files - especially still photos or videos - in seconds rather than minutes.

Qualcomm says that while HSUPA used to be allocated only to the high end chipsets (for use on high end phones) it's now being included as standard for chipsets aimed at 'mid range' devices and by the end of the year will appear as standard on low end phones as well.
Why the adoption spurt? Mobile social networking and user generated contents are the main reason. Where many traditional data applications, such as receiving email, web browsing, and music and video downloading are overwhelmingly asymmetric (far more data coming down than going up) the coming mobile social networking wave looks likely to demand huge amounts of uplink capacity as users begin to use the features of their new upscale phones in earnest. High resolution multi-megapixel cameras mean big, chunky picture files; easy video capture means even larger video files; and new applications involving pictures and location, via GPS, require high quality, reliable connectivity back to the controlling server.


According to Qualcomm, mobile social networking will finally and resoundingly answer the question: Why do we need 3G?

We'll need it because the evidence shows that users are interested in taking social networking out of the confines of the tethered PC, and putting it on the road via their mobiles where it can blend with and enhance real, physical, non-virtual social networking: the sort which involves real people moving about and doing things in real places.

So users are fast moving beyond SMS and towards applications and services which will enable them to really share their activities at, say, live events.

So let HSUPA roll and let the fun begin.