Black-listed and White-listed cells in E-UTRAN

One interesting thing done in LTE is that when System Information is transmitted, there is a list of cells known as ‘blacklisted’ cells. These black-listed cells can be Intra-frequency, Inter-frequency or Inter-RAT cells. These are the cells that UE should not consider while doing measurements, handovers or cell-reselections. The other list that the UE should consider is referred to as the white-list.

The black-listing is provided in the SystemInformationBlockType4 and SystemInformationBlockType5 that is transmitted by RRC in E-UTRAN.

By providing a black-list of the cells, the UE can avoid wasting time performing measurements on that frequency and then reading the System Information only to find out that there was no point of doing this operation. At the same time the neighbour list can be reduced and the amount of cells the UE reports in measurements can be reduced. The UE can also re-select to a new cell faster because the neighbour cell list size is reduced.

The possible reasons for black listing could be that a cell is reserved for operator then the UE's should not be able to use them. Similarly if the cell is reserved for future use or reserved for private use (Femtocells?) or in a scenario where it wont be possible for the UE to reselect it (Examples are cells that are separated by a river and micro cells that are in two different skyscrapers, etc).

I havent gone through the specifications in detail yet but it may be possible to use this information in case of Femtocells. The neighbouring Femto's can be included as black-listed cells so that the UE dont try to camp on them.

M is for Manga - Comics on the Mobile

The Independent newspaper has an interesting photo gallery on the Japanese Comics, better known as Manga. Check it out here.

LTE design requirements

There have been many discussions and articles written about LTE in the past one year or so. As LTE is pushing forward so is the design and implementation phase for different companies involved in LTE development. Following are the requirements for LTE which engineers should take into account while designing the LTE system.

Capabilities:
The targets for downlink and uplink peak data-rate requirements are 100 Mbit/s and 50 Mbit/s, respectively, when operating in 20 MHz spectrum allocation. For narrower spectrum allocations, the peak data rates are scaled accordingly. Thus, the requirements can be expressed as 5 bit/s/Hz for the downlink and 2.5 bit/s/Hz for the uplink. Obviously, for the case of TDD, uplink and downlink transmission cannot, by definition, occur simultaneously. Thus the peak data rate requirement cannot be met simultaneously. For FDD, on the other hand, the LTE specifications should allow for simultaneous reception and transmission at the peak data rates specified above. LTE should support at least 200 mobile terminals in the active state when operating in 5 MHz. In wider allocations than 5 MHz, at least 400 terminals should be supported.

System performance:
The LTE system performance design targets address user throughput, spectrum efficiency, mobility, coverage, and further enhanced MBMS.

The LTE user throughput requirement is specified at two points: at the average and at the fifth percentile of the user distribution (where 95 percent of the users have better performance). A spectrum efficiency target has also been specified, where in this context, spectrum efficiency is defined as the system throughput per cell in bit/s/ MHz /cell.

In terms of mobility LTE should be able to provide good rates even when the user is moving at 500km/h

Deployment-related aspects:
The deployment-related requirements include deployment scenarios, spectrum flexibility, spectrum deployment, and coexistence and interworking with other 3GPP radio access technologies such as GSM and WCDMA /HSPA.

The requirement on the deployment scenario includes both the case when the LTE system is deployed as a stand-alone system and the case when it is deployed together with WCDMA/HSPA and/or GSM. Thus, this requirement is not in practice limiting the design criteria.

The coexistence and interworking with other 3GPP systems and their respective requirements set the requirement on mobility between LTE and GSM, and between LTE and WCDMA/HSPA for mobile terminals supporting those technologies. Table below lists the interruption requirements, that is, longest acceptable interruption in the radio link when moving between the different radio-access.

Spectrum flexibility and deployment:
The basis for the requirements on spectrum flexibility is the requirement for LTE to be deployed in existing IMT-2000 frequency bands, which implies coexistence with the systems that are already deployed in those bands, including WCDMA/HSPA and GSM. A related part of the LTE requirements in terms of spectrum flexibility is the possibility to deploy LTE -based radio access in both paired and unpaired spectrum allocations that is LTE should support both Frequency Division Duplex (FDD), and Time Division Duplex (TDD).

Architecture and migration:
A few guiding principles for the LTE RAN architecture design as stated by 3GPP are:
A single LTE RAN architecture should be agreed.

The LTE RAN architecture should be packet based, although real-time and conversational class traffic should be supported.

The LTE RAN architecture should minimize the presence of ‘single points of failure’ without additional cost for backhaul.

The LTE RAN architecture should simplify and minimize the introduced number of interfaces.
Radio Network Layer (RNL) and Transport Network Layer (TNL) interaction should not be precluded if in the interest of improved system performance.

The LTE RAN architecture should support an end-to-end QoS. The TNL should provide the appropriate QoS requested by the RNL.

QoS mechanism(s) should take into account the various types of traffic that exists to provide efficient bandwidth utilization: Control-Plane traffic, User-Plane traffic, O & M traffic, etc.
The LTE RAN should be designed in such a way to minimize the delay variation (jitter) for traffic needing low jitter, for example, TCP/IP.

Radio resource management:
The radio resource management requirements are divided into enhanced support for end-to-end QoS, efficient support for transmission of higher layers, and support of load sharing and policy management across different radio access technologies.

The enhanced support for end-to-end QoS requires an ‘improved matching of service, application and protocol requirements (including higher layer signalling) to RAN resources and radio characteristics. ’ The efficient support for transmission of higher layers requires that the LTE RAN should ‘provide mechanisms to support efficient transmission and operation of higher layer protocols over the radio interface, such as IP header compression.’ The support of load sharing and policy management across different radio access technologies requires consideration of reselection mechanisms to direct mobile terminals toward appropriate radio access technologies in all types of states as well as that support for end-to-end QoS during handover between radio access technologies.

Complexity:
The LTE complexity requirements address the complexity of the overall system as well as the complexity of the mobile terminal. Essentially, these requirements imply that the number of options should be minimized with no redundant mandatory features. This also leads to a minimized number of necessary test cases.

General aspects:
The section covering general requirements on LTE address the cost-and service related aspects. Obviously, it is desirable to minimize the cost while maintaining the desired performance for all envisioned services. Specific to the cost, the backhaul and operation and maintenance is addressed.

QR Codes in Newspaper Ads to redirect mobiles to web content

Canada's National Post newspaper began using two-dimensional (2D) bar codes this week to link newspaper articles to video and other content.

The link from paper to the Web is made possible through a free downloadable mobile app for smartphones from Scanbuy, N.Y. Directions on nationalpost.com point visitors to getscanlife.com. When the camera on the phone takes a picture of the bar code, the application reads the embedded information in the code and triggers a Web browser to open, which searches the Internet for the URL and serves up the page on the phone.

National Post hopes to offer advertisers a print ad service that gives consumers options to discover more information about products and services on the Web, according to Scanbuy CEO Jonathan Bulkeley. He noted that Canwest Publishing is the largest media company in Canada.
The deal adds to the hundreds of thousands of people that have already downloaded software from Scanbuy's Web site during the last six months. "We're supporting hundreds of scans per day in the United States," Bulkeley said, suggesting that people can go to the site, create a 2D bar code and download it for free. "The codes are put on t-shirts and other marketing items to promote brands."

In the past few months, Scanbuy has signed deals with telecom carriers such as Alltel, before being acquired by Verizon, and Sprint, which will soon begin to ship handsets with the 2D bar code readers preloaded on phones. Today, the software is available to download on 45 phones. Nike ran a soccer promotion in Mexico, as did Fanta in Denmark and Scandinavia using 2D codes, Bulkeley said.

Bulkeley said he has been considering getting a 2D bar code tattoo to have something readily available that can demonstrate the technology. "You could have one code and continually change the link behind it to pull down different content," he said. "It's like redirecting a URL."

Watch the Video here:

Via: Daily Wireless

New Blogs on the Block

There are couple of blogs which I found useful and have been started this year.

3GPP Wireless Technology Demystified
This is by my colleague Venu Panchamukhi and its a very technical blog covering HSPA, HSPA+ (Release 7) and hopefully HSPA Evolution (Release 8) soon.

Wired n Wireless
This is another technical blog with focus on LTE with a mix of some other news.

If you are a new blogger and would like everyone to know about your blog then please feel free to add your blog in the comments. No Spam please as I am going to check each of the links before approving it. Also note that the blog should be related to telecoms, wireless, 3G, 4G, etc.

IMS Deployment and Future Strategy

A very interesting post by Christophe Gourraud in The IMS Lantern. If you are even remotely interested in IMS then you should read the post here.

Qualcomm to put Femtocells in Mutant Animals ;)

In the latest breakthrough from its labs, Qualcomm has perfected a new version of its system-on-a-chip (SoC) technology that can be embedded into animals, turning them into living, breathing highly mobile femtocells. By creating biological femtocells, Qualcomm is allaying one of the critical weaknesses of the wireless network: while the devices on the network are mobile, the infrastructure of the network is static. By turning the family dog, for example, into a femtocell, the issues of dead zones and coverage gaps disappear as coverage moves with you wherever you—and your dog—go.

Research into these dynamic biological networks is still in its infancy, but Qualcomm has released a demo video on the technology, which you can view below. As part of that research, Qualcomm is trying to overcome what it sees as the inherent limitations of many species of animals. Pigeons, for instance, could be used to create a pervasive flying network in any heavily trafficked downtown area, but the pigeon isn’t the most long-lived of animals and it has several predators, thus requiring an operator to constantly reintroduce new pigeons into the network to maintain capacity levels.

Qualcomm has solved that problem through genetic engineering. It has crossbred a pigeon with a wolf, creating a hardier more aggressive femtocell that can defend itself from both predators and the elements. The only problem with this approach, though, is its high susceptibility to industrial espionage. A rival operator could introduce biological femtocell predators into a market, to attack, maim and possible even eat another operator’s femtocells. While bio-engineering femtocells such as the wolf-pigeon might seem a natural defense mechanism against tactics, the rival operator could always engineer a better femtocell. Qualcomm demonstrated how a shark crossbred with a hawk could effectively nullify a femtocell networks composed of wolf pigeons.

See the Video below:




By the way, I hope you have realised that it was an April Fools joke :)

Mobile Screensaver helps catch a burglar

This story can probably be nominated for the most stupid awards.

A bungling burglar was caught out after he left his mobile phone - with a picture of himself on the screen - in a house he had broken into, police said.

Richard Hannah was jailed for six years today after he was found guilty of burglary by a jury at Nottingham crown court.

Hannah, 30, was confronted by the owner of a house in Mansfield Woodhouse, Nottinghamshire, after he broke in at about 4am on 15 September last year.

After a scuffle between the pair, Hannah, from Poplar Street, Mansfield Woodhouse, left his mobile phone, with a screensaver photo of himself, at the house.

Hannah was found guilty today of burglary after a three-day trial, despite claiming the phone had been stolen and left by someone else.

He was jailed for six years under the government's "three strikes and you're out" crackdown, Nottinghamshire police said.

Future Phones will be able to understand your thoughts

Honda is working on a technology for Robots in Japan where they can understand the owners thoughts. Right now only four commands can be understood but the success rate is 90%. If this technology becomes successful it can probably be applied to phones as well.

I remember reading (cant find link, sorry) that NTT DoCoMo has already developed a prototype of phone in which you can speak without any sound and the person at the other end wont even notice. He will hear normal voice.

NTT DoCoMo launched Motion sensing phones couple of years back and the main idea was that the user can control things by motion of their hands. I havent dug into details but I can visualise myself in future working on my laptop and just by waving my hand ask my mobile to start composing a text message. I would be able to dictate the message and just with another wave of my hand, the message will be sent.

Japan has always been the leader of these kinds of technologies and companies out there are working hard innovating new technology. NTT DoCoMo (again) showed off last year a technology where the volume can be controlled just by rolling the eyes. At the moment all these things involve some kind of human attachment which makes them impractical for the time being. In future hopefully there will be better alternatives and more reliable technologies like these.

Anyway, we wont see any of the above technologies anytime soon. There is a funny video on Youtube that you will like about these future technologies that is available below:

HSPA based Laptop Enabler/Disabler

Ericsson (NASDAQ:ERIC) today unveiled its most advanced mobile broadband module, uniquely designed with innovative features to provide a richer and cost-effective internet experience for all. The next-generation module marks the latest milestone for Ericsson, furthering the company's vision of an all-connected world.

Ericsson's F3607gw mobile-broadband module for HSPA/GPRS/EDGE networks, to be released in June, will provide enhanced functionality and convenience through its innovative features, reduced power consumption, prolonged battery life and an increased level of integration, reducing the number of necessary components and therefore cost. The new module will also provide built-in mobile broadband support for Microsoft Windows 7.

Mats Norin, Vice President of Ericsson Mobile Broadband Modules, says: "The combination of leading technology and innovative design in the next-generation module is key to delivering a superior user experience at an affordable price. This module release confirms Ericsson's commitment to making the benefits of connectivity available to everyone."

An important facet of the F3607gw is the unique wake-on wireless feature. By remaining connected while a notebook or netbook is in sleep mode, the module's wake-on wireless feature enables users to remotely wake up the device. This innovative technology will allow a new set of applications to be built into the computer to further enhance security and instant-on functionalities, such as the ability to disable the computer in case of theft, or instant distribution of important messages and security updates.

Operators can also combine the wake-on wireless feature and embedded GPS functionality to create a range of differentiating services for consumers and the enterprise market, including remote manageability, security updates, asset protection and tracking and geo-fencing. The module can also be used for content push services, such as podcasts, public warnings, traffic updates and database updates.

Specifically, the wake-on wireless feature supports security solutions based on Intel's Anti-Theft PC Protection Technology. An anti-theft management service in the network can send a message via SMS to the mobile-broadband module inside the notebook, which securely transfers the message to Intel's Anti-Theft function inside the processor platform. This takes appropriate actions, such as completely locking the computer and making it unusable. When the notebook is located and recovered, an unlock message can be sent to the notebook that makes the data accessible again.