Saturday, 23 May 2009

Amazing iPhone Apps

In the year 2008 the Smartphones took the consumers to different levels and iPhone has been a revelation which was embraced by the masses. What is most striking in the success of the iPhone is the applications which are available on it.

Below are the top 10 iPhone applications.

1 Pandora Internet Radio

This application is available free with the iPhone and is all-time best for music lovers. You pick a song, album or artist and Pandora immediately builds a whole "radio station" around it, endlessly streaming complete tunes from top artists. You can even tweak your station by giving songs a thumbs-up or thumbs-down. Music quality is amazingly good for audio and as far as I know the audio streams for free over AT&T's data network. The music library is solid for genres ranging from rock to pop to jazz to classical. It really needs some Indian Bollywood music, though.


2. AroundMe

Simplicity makes this app a must-carry for the road warrior. Like the name applies, it lists all the critical services around you i.e. banks, coffee shops, bars, gas stations, hospitals, movie theatres, restaurants and so on. Using geo-location, the app orders each service by its proximity to you by giving further details like how many yards away the bar is(I would be mostly interested in that). This apps is very much aimed at the traveller and like any other apps it maps out a route from here to there, if requested. It also creates a contact page for every entry, which you can save to your own contacts list.


3. Mobile News Network

The Associated Press's news-on-demand app is the gold standard. It gives you top news stories, as well as business, sports, show biz and other categories, which you can sort by most recent or most read. It even uses the phone's GPS chip to deliver up local news. Stories and photos load fast, look great and can be read offline. You can email or text the story to a contact, or save it in your own news archive.


4. Ocarina

Some genius figured out how to use the microphone on the iPhone as an air-flow sensor, as a result now we've got a virtual ocarina, albeit not potato-shaped. Hold the phone up to your lips and blow; four "holes" appear on your touch screen allowing you to play almost any scale (which you select under Settings). Share your tunes with other Ocarina players around the world, or just set the app to listen to their masterworks. The Ocarina app costs $0.99 in US from the AT&T network.


5. Wikipanion

O.K., so it's not always accurate. But if you need to understand the gist of something, there's no better reference tool at your fingertips than Wikipedia. While there are many Wikipedia apps for the iPhone, this one is the best of the bunch. It automatically searches while you type, which is cool as well as time-saving, and its rendering of the Wikipedia page on the touchscreen is as perfect as you'll find. By upgrading to the pay version, Wikipanion Plus, users can save articles and do offline browsing.


6. Adrenaline Pool Lite

Virtual pool has been around since the advent of computers. It wouldn't be surprising to hear that it was first played on the UNIVAC 1. And like everything else with a chip for a brain, e-billiards continues relentlessly to improve — this app being a case in point. Fire up Adrenaline Pool, log into a server, and you can play anything from eight-ball to snooker, against other anonymous iPhone pool sharks. The physics are so good; you'll want to take up smoking again.


7. Instapaper

Sign up at Instapaper.com for a free account then drag the "Read Later" tag to your browser's toolbar. Now, whenever you're sitting at your computer and stumble upon an article or blog post on the Web that you'd like read later, hit that button. Instapaper's app instantly stores it on your iPhone in a format that's especially readable.


8. NetNewsWire

There's no better way to keep up with your daily perambulations on the Net than via an RSS reader, which basically pushes content from any website or blog to your computer in a format that resembles email. NetNewsWire is one of the best free programs for computers, allowing you to easily subscribe to any feed and synchronizing what you've read across any computers you use. This app adds your iPhone to the party, allowing you to read perfectly formatted text on demand, as well as offline.


9. iTalk

A reporter's best friend, but also indispensable for anyone who wants to dictate memos or record other audible stuff on their phone. The app is little more than a big, red RECORD button on your iPhone screen; push it to capture audio in the high-quality AIFF format. What makes iTalk especially cool is the free, companion iTalkSynch app, which you download to your computer. That program can "sniff" the audio files on your iPhone and download them to your Mac or PC, via Wi-Fi. Now all we need is an app to do perfect voice-to-text translations


10. FakeCall

Because everyone needs a decent, iPhone party trick. Set up a fake contact and that person calls you, on demand. Great for getting out of dull business meetings, or impressing friends when Steve Jobs calls to ask if you really, truly think cut-and-paste would be a good thing to have on the iPhone.

Together with the above Apps there are so many programmers around the world who are busy in writing or developing some more interesting Apps on the apple i-phone Apps store. One of the most interesting I came across recently was a British-made iPhone program that allows the user to read the Kama Sutra.


Eucalyptus, a book reading application developed by Edinburgh programmer James Montgomerie, allows users to download and read thousands of classic titles from the library of Project Gutenberg, the respected website that hosts out of copyright books.But after repeated attempts to get Eucalyptus onto the iPhone's popular App Store, Montgomerie was told that his application was being rejected because one of Gutenberg's books happens to be Sir Richard Burton's 1883 translation of the famous guide to sex.


The link below from Guardian UK tells you more about the above story.

http://www.guardian.co.uk/technology/blog/2009/may/21/apple-iphone

LTE World Summit: Day 3 roundup



I started the third day with my Breakfast briefing. You can see the details here. The third and final day was the deployment day so there were lots of operators speaking.

Pierrre Lescuyer from SFR, France talked about the Spectrum challenges for LTE. SFR is by the way, second largest operator in France with nearly 20 million customers. The key factors for success of LTE would be to have 2.6GHz and UHF band to be bundled together. Also the backhaul has to be improved. The Digital Dividend band in France will be available end 2011 and there is going to be protection of broadcasting below 790MHz. The French goverment has announced the auction of remaining 2.1GHz band and started consultation in 2.6GHz band. In the 900MHz band, there is not enough spectrum for everyone to co-exist. The 2.6GHz band is good for hotspots giving 2x20MHz bands and LTE could also be deployed in the 1800 band with 2x10MHz bands. LTE 800 is another alternative but the existing antennas will have to be replaced.

Franz Seiser from T-Mobile Germany, VoLGA (Voice over LTE Generic Access). The main reason for VoLGA is because the current solutions for voice do not meet all LTE requirements. CS fallback is not good enough because of the time it takes for establishing the call and has lots more impact then originally envisaged. Also the MSC would have to be upgraded to Rel-4 for this feature to work. IMS solution is again not good enough because of high complexity; availibility and stability not feasible in time for rollout. Also what happens in case like Femtocell where CS fallback is required and no 2G/3G network is available? To overcome this VoLGA was proposed. Its the best compromise and elegant approach to solve Voice and SMS problems in LTE early.

Prof. Patrick Marsch, Technical Project Leader EASY-C, Vodafone Chair Mobile Communications, Germany spoke about the Easy-C project. Apparently, Easy-C has already been doing the things identified by the LTE-Advanced comittee. Their requirements were mentioned in slightly different terms then the standards one. For example, "Click and Bang", "Click and Wow", etc. The main aim being Inexpensive throughput, anytime, anywhere. I will look into the details later.

Thierry Maupile, VP, Starent Networks spoke about the readiness of the Core for high amounts of data traffic predicted. The main growth for mobile broadband will come by having higher bandwidth true multimedia devices, friendly devices and easy access to applications, payments, etc. By 2014, more than 4 petabyte data will be flowing through some operators. This can cause major challenges in the multimedia core as there will be a massive increase in the signalling. To overcome these challenges, simplified All-IP architecture will be required. Voice grade reliability is another important factor and so is security. Starent claims to be a leader with support for multiple technologies in the same platform. It concentrates only on the PS core and has 95+ operator deployments in 40+ countries. Its core is used by 8 of top 10 3G operators and its #1 in UMTS PS cores.

Rodrigo Cárdenas, Deputy Director of Technological Evolution, Entel PCS, Chile spoke about Deploying Next Generation Technologies such as LTE in Latin America. Chile, surprisingly ranks #9 in the number of facebook users. Since the landlines connectivity is quite limited in Latin America, mobile has good chances of growth if the pricing is correct. With some clever pricing, the mobile broadbank uptake has grown 249% recently. Even high quality mobile TV encoded at 240kbps is being delivered. In Chile, HSPA is good enough for the time being with migration to HSPA+ in near future. LTE will be useful for Corporate broadband or for HDTV on mobile. It can also be used as main broadband connection at home and can complement satellite. 2.6GHz is the main band for South America with other possibilities being 1700/2100MHz or even 700MHz.

Rick Keith, Director of Global Strategy, Motorola spoke about LTE for the Operator in an Emerging Market. There were lots of facts and stats to mention right now but the main point being that LTE can address digital divide in rural areas (developed as well as developing countries) and an early launch of LTE will open possibilities for new revenue.

Javier Sanchez, from Zain, Kuwait soke on similar topic of LTE for the Operator in an Emerging Market. Zain is present in 24 markets. It has got 62 million customers. Recently they have started the "One Network" which allows users from any of their countries to roam to other country and use the phone as local. That means the price of international calls is still local and they can even top-up using vouchers locally. '3' in UK have done something similar even though its not exactly the same. One of the thing Zain has done is that rather than subsidising devices, they have subsidised bundles. The main criteria for success according to them is to make mobile broadband more affordable for everyone. This means to create possibility of low entry price

Please note that all the details I mentioned are from my notes or memory. I havent dived into the presentations yet. When I do, I will mention things in more detail and may correct myself. In the meantime if you spot something wrong please feel free to comment.

Friday, 22 May 2009

Killer Applications or Devices

Here is my breakfast briefing presentation.


As expected, we had a very lively and interesting discussion. It is not easy for me to remember and detail the discussions but the presentation will give some idea regarding the things we discussed. I also referred to a presentation about Japanese market which is embedded below.


Please feel free to comment, criticise, suggest, etc.

LTE Femtocells: Stepping stone for 'killer apps' presentation

This is my presentation from last year. I added this because some people asked me for this. Please feel free to comment.

Thursday, 21 May 2009

LTE World Summit - Day 3 Pics

Some Pics from day 3.

This is from my breakfast briefing session.


The above are Signallion Test UE. Check the 'SORBAS Test UE' flyer here.

Thats the Signalion's test engineer running some simulations ;)


Qasara's LTE Protocol stack. See their presss release.



Everyone enjoying the break on the last day.

LTE World Summit: Day 2 roundup



I had been enjoying some delicious Thai food yesterday night and as a result didnt wake up on time for the Breakfast briefing. Adrian Scrase, the 3GPP VP started and managed the morning session. I have always enjoyed him speaking and chairing events as he is full of knowledge and quite practical about the technologies.

Hans Erik Karsten from Telenor, Norway, spoke asbout the Norway market and gave some interesting facts and figures. For example, 2% of users are using 40% of the capacity and these are the PC users. 10% of the users use 80% of the capacity. In fact one person downloaded 230GB of data in a month (flat pricing schemes ;). N95 users use 10 times the data of an average phone. From Telenor point of view, LTE is an evolutionary step. The main advantage of LTE is flexible spectrum usage. They are also exploring Femtocells and Self Organising Networks (SON) will be the key. There are many upgrade paths from GSM/UMTS to LTE but there is no single solution for all different markets. Sweden will rollout LTE asap in 2.6GHz and 900MHz in future. Norway will be 2nd.

Julius Robson from LSTI (and Nortel) spoke about Industry wide trials and IOT. LSTI have now done real world analysis rather than the peak rate analysis and there were lots of interesting facts and figures that I will dive in later.

There has been lots of mention of refarming of 900MHz band and 'Digital Dividend' band. It was mentioned couple of times in the Panel discussion as well. Deploying LTE in 1800 band is not favioured by some as it wont provide much advantage over the 2.6GHz band regarding the coverage. Nakamura-san from NTT DoCoMo mentioned that none of the operators in Europe use Tx-Diversity and it is possible that MIMO will be deployed selectively in higher bands initially. There is a new initiative in Femto forum to open up Femtocell API's to third party and we may see in future that these API's may be opened up on Macro cells as well. See this blog post I did earlier.

Paul Steinberg from Motorola discussed about the cost and capacity. Again lots of facts and figures that I will dive in later. Interesting fact mentioned was 75% of users watch online video. According to him, LTE satisfies capacity and decreases TCO (Total Cost of Ownership). One of the advantages of OFDM is that there is no cell breathing (unlike WCDMA), there is SON and spectral efficiency is 3-4x. He also mentioned about the green advancements that Motorola have achieved. They are able to show 8x reduction in power requirements. There was some discussion about the bands and they think the first bands to be used would be 2.6GHz followed by 800, 900, 700 (Digital dividend bands which are different in different parts)

Doug Wolff from Alcatel Lucent talked about the US market. He mentioned that Verizon and AT&T has 60% US coverage. I will have to go in detail on this one later.

Adrian Scrase talked about 3GPP release 8 features and mentioned about the other main non-LTE features in Rel-8 namely ETWS, eCall amd ICE. I have talked about ETWS here and ICE here. Will discuss eCall in a future post.

Stephen Hayes from Ericsson talked about Rel-9 features. There are lots of things I want to talk about but it will have to wait for another post. I have already mentioned some of Rel-9 features here but will have to update the list soon.

Takehiro Nakamura from NTT DoCoMo talked about Release-9 and LTE Advanced and about Relay features in LTE Advanced. This presentation will probably end up on my LTE-Advanced page.

Charles Brrokson who is ETSI Security chair spoke about security in LTE and Rel-8 and how its different from UMTS. Its too technical to be covered in this post.

Giovanni Romano from Telecom Italia in Italy talked about their strategy and plans in Italy. He mentioned that there are already 1409 HSPA form factors available and hence they plan to have atleast 80% coverage in Italy for HSPA first. Later they have to think about moving either to HSPA+ or to LTE. The move to LTE will also depend on if Spectrum decisions have been made and the status of LTE device test certification.

Finally, Eiko Seidel spoke about LTE-Advanced and Rel-10. Will have to wait for another post though.

Wednesday, 20 May 2009

LTE World Summit - Day 2 Pics

Here are few Pics that I took today.


The R&S CMW 500 is seen to be doing MIMO testing with LG UE. The throughput was reaching upto 60Mbps.

Thats the LG LTE UE being used by R&S.

Thats the Anritsu MD8430 LTE Network Simulator and MD8435 UE Simulator. They were showing throughputs of 100Mbps DL and around 45Mbps in UL. The RTD tool (I am going to cover that in a seperate blog in few weeks time) can be seen on top right.

Anritsu engineer working ;)

Tektronix simulators. Apparently they have a solution for everything from drive testing to Femtocell test equipment. Hopefully more later

I also went to Ericsson Demo/Roadshow for LTE, HSPA and IMS Technologies. Unfortunately they didnt allow anyone to take any photographs.

Tuesday, 19 May 2009

LTE World Summit - Day 1 roundup


Before we start, I should mention that there have been no discussions showing LTE is better than WiMAX, etc. It is now assumed that WiMAX is no longer a threat and a competitor. There is also missing a discussion on Femtocells. I suppose that some Femto related discussions are planned for day 3.

I am going to cover the discussions in detail in the coming days (months) but here are some interesting tidbits.

It started with a presentation from Marc Fossier, France Telecom. An interesting fact about France he mentioned is that 40% of voice traffic is VoIP. They are present in 30 countries (generally by the name Orange) and they have 128 million customers. LTE rollout is planned for post 2011. They will be deploying WiMAX in some markets like Romania and some African countries. The main reason being that there is no 3G network there. Another key point of his presentation was that Mobile TV should be independent of the technology being considered and TDD works fine for that. Also SON (Self Organising Networks) will be very important feature that is needed when LTE is rolled out.

Klaus-Jurgen Krath from T-Mobile Germany gave T-Mobile statistics of 148 million customers and revenue of 9.2 Billion Euros. One of the things he mentioned is that at 2.6GHz, the cell radius is 0.3Km but if we move to 800MHz then the cell radius is around 3Km. Personally I am not sure if the frequency is something we should worry too much about. WiBro in Korea is I think using 2.3GHz and is working fine. Another thing mentioned is that the Backhaul is generally quite bandwidth limited so that needs to be improved. The operators should use Microwave or Fiber to overcome this backhaul problem. LTE Migration will also take time and initially it would be the third layer on top of GSM and 3G/HSPA but by 2020 it should be dominant technology. Right now Voice and SMS problem has to be solved asap. Personally I think SMS is not much of a problem and SMS can work on CS as well as PS. Operators can use SMS over PS for the moment. Femtocell according to Klaus is very important for LTE but Femtos will be successful only if they are Plug and Play for both operator and the consumer. His final point was that we should not dissapoint the customer by showing the peak rates, rather we should focus on average rate.

Ulf Ewaldsson from Ericsson mentioned that 80% of broadband subscribers by 2014 will be mobile. Another thing he said is that for LTE, it is possible to deliver 1GB for < 1 euro. (Capex only). Ericsson vision is that by 2020 there will be 50 Billion mobile broadband connections. Ericsson will be ready with LTE soon and by the year end peak rate of 42Mbps will be possible.

Alex Sinclair from GSMA talked on expanding the LTE ecosystem. There were lots of interesting facts and figures that I will have to mention seperately. There was also an intersting mention of the GRX (GPRS Roaming Exchange) that will need a completely new discussion.

In the Panel Discussion, Marc mentioned that Orange is not considering Femtocells for Residential market because of many unsolved technical problems like Price, Security, Spectrum Management, etc. On the business side they may have Femto, Pico or Micro depending on the need. Ed Candy from '3' mentioned that operators should focus on Macro rather than Femto because lots of spare capacity available. He mentioned that there is a business problem because somebody has to subsidise Femto, also too many Femtos can cause RF blackspots and operational dynamics are yet to be worked out.

Elio Florina from Telecom Italia (TiM) talked about LTE and HSPA deployment in Brasil. The main point being that initially they want to have complete 3G/HSPA coverage and then in future think about LTE.

Alan Hadden from GSA mentioned about GSA activities. I was surprised to hear that only 55,000 people view their website annually. This is because a simple blog like mine regularly gets between 20,000 and 25,000 views per month. Again there were lots of stats that I will write about later. Interesting point from his discussion was about the Digital Dividend band that can be used by LTE to increase the coverage.

Dave Marutiak, Microsoft spoke about Bearer Aware Applications. Dean has blogged in detail about this.

Ed Candy from '3' in his presentation highlighted an important point about the user experience. He said that for any service, user experience should be memorable so even after 2-3 years if the user has to use the same application than he should remember how it works. I think that there are hardly any services like this except those that are intutive to use. In Dec. 08, '3' saw people using 34million skype minutes and 68 million Facebook page views. It should be remembered that Facebook phone was launched in Dec itself. His message was that '3' will not be moving to LTE anytime soon because the current network is delivering whatever is required.

Roberto Di Pietro from Qualcomm spoke about the challenges faced by the chipset manufacturers. The main challenges is due to the fact that there are millions of combinations of different bands that the UE may need to support which is not practical and possible. They are focussing mainly on 2.6GHz at the moment and when the Digital Dividend band is available then they will implement chipset in that band as well.

Jorgen Lantto from ST-Ericsson and Sami Jokinen from Nokia gave their views on chipsets and handsets implementation respectively. According to Nokia, LTE handsets will be available by 2010. Initial deployments will be in FDD but later in TDD-FDD both.

Liesbet Van der Perre from IMEC discussed about the SDR implementation for LTE devices. Her presentation was more of updates on the previous IMEC info I have covered here.

Finally, I managed to squeeze myself into an Agilent workshop called 'LTE at the movies'. There were two parts to that 'MIMO MIA' and 'Honey who shrunk my mega bits'. The workshop lated 2.5 hours and I got a free Agilent LTE book. Lots of technical details that I will post seperately.

Please feel free to comment or correct me if I made any mistakes. You can also read Dean Bubley's take on the first day here.

I shouldnt finish without thanking the organisers who have done a good job in organising the event and for such wonderful hospitality (and food :).

LTE World Summit - Day 1 Pics

We had an interesting first day at the LTE World Summit in Berlin. There were no breaking news though. Summary coming in the next post after the Pics.

The lunch was sponsored by Starent Networks. Here is a Pic of their cake. Nice cake but I dont like chocolate cake. I would have preferred strawberry ;)

This above is Agilent's test mobile that can be used for drive testing.

Agilent has a massive and impressive presence here. I attended their workshop yesterday, will report the details later.


Ericsson are showing off the new TEMS that can be used for LTE drive testing, etc.


mimoOn are showing their Test Mobile and their complete solution for eNodeB, etc.
Very interesting to see LTE Test Mobiles from 3 companies already available.



Setcom is a new entrant (even though they have been present for long time but I never heard of them before) in Network Simulator area. They have plan to do Conformance tests for the LTE mobile. They claim to be ready already with basic test functionality. Till date the Conformance test market have been dominated by Anritsu, Agilent (Anite), Aeroflex and R&S. I have already heard of AT4 Wireless being active in this area for LTE. It would be interesting to see one more player.

Monday, 18 May 2009

In Berlin for LTE World Summit

Just a day in Berlin to look around is not enough, especially if you are a bit tired due to your journey. I managed to go round to few places though and Berlin does look like a place that need to be explored.

Here are some photographs from Berlin:









All the above photographs are from The ruins of the Kaiser Wilhelm Memorial Church in Berlin, destroyed by Allied bombing in Second World War and preserved as a memorial








The final pic is of the Berlin Aquarium. Maybe the next visit, I will go and check it out.

Saturday, 16 May 2009

New LTE Patent Pool attempt

Via Licensing Corp. is looking to administer a patent pool for companies and research institutes claiming to have Intellectual Property for the emerging fast date rate cellular technology Long Term Evolution (LTE).

Last April a group of equipment vendors and handset makers already teamed up to craft a licensing framework for the fourth-generation mobile standard that is based on the 3G Partnership Project's (3GPP) E-UTRA Series 36, release 8 specifications.

The equipment vendors and handset makers that teamed up in April 2008 to establish rules for licensing patents related to the technology included Nokia, Nokia Siemens Networks, NextWave Wireless, Alcatel-Lucent, Sony Ericsson, NEC and Ericsson. They decided to push for "fair and reasonable" licensing terms for the patents related to the so-called 4G wireless network technology.

MPEG LA LLC (Denver, Colo.), the organization set up to administer access to MPEG patents, but which has also branched out into other sectors, has also started working on a patent pool for LTE and has said that several companies have already shown interest in participating in its pooling efforts.

MPEG LA, LLC recently announced that it has made significant progress working with a group of interested companies to facilitate creation of a joint patent pool license for the Long Term Evolution (LTE) Standard for mobile telecommunications. MPEG LA’s efforts, started last year, have been directed toward educating the market about the benefits of a pool license to address the patent thicket around this next generation wireless technology and assist the market with its adoption.

“The market is ready, and we are proud that industry leading companies have invited us to facilitate creation of an LTE pool license,” said MPEG LA President and CEO Larry Horn. “Given the history of telecommunications patent pools, MPEG LA has taken the time to consult directly with mobile network operators, network equipment manufacturers and mobile handset companies regarding the benefits of a patent pool for LTE, and they have encouraged MPEG LA to move forward with this effort. We are pleased by their vote of confidence. Next generation wireless technology, with its multifunctional capabilities, begs for a patent pool licensing alternative to make its full potential available to consumers worldwide, and MPEG LA’s success in creating large pool licenses uniquely positions us to achieve it.”

Via already administers patent pools for a number of technologies, notably in the broadcast, audio and wireless space, including those for MPEG2, 802.11 based Wi-Fi and near field communications (NFC). The company is a spin-out from Dolby Laboratories Inc.

Via can’t force patent holders to play, and without a majority of solid patents with which to negotiate, its attempts will fail. There’s little reason for a larger company to join a patent pool, unless it wants to help push through a standard, which isn’t the case with LTE.

Patent pools have become increasingly popular in recent years to handle licensing in cases of relatively large numbers of patent holders and licensors. The pools can help lower transaction costs and reduce uncertainty and time spent negotiating deals, sometimes with competitors across barriers of language and geography.

Generally, the cost of intellectual property associated with cell phone radio standards has been far higher than devices based on open standards such as Wi-Fi or WiMAX. That means that devices with cellular radios have been more expensive, as have the network equipment costs. I doubt industry players — including Qualcomm, which own LTE patents — are going to be eager to reduce their potential royalty income in exchange for letting Via manage the licensing process. Especially since folks at many of these firms already have the staff and knowledge to handle cross-licensing agreements.

Friday, 15 May 2009

Testing UMTS protocols




Testing UMTS by Dan Fox, Anritsu

Its nearly three years since I wrote an FAQ on UMTS Testing. So when I got my hands on this book the other day, I so wanted to read it. It would be a while before I manage to go through the book in detail but my initial impression is that this book looks quite good.

Since the book deals with Protocol Testing, the testing has been grouped into three categories:

  1. Integration Testing
  2. Conformance Testing
  3. Interoperability Testing

There is a chapter explaining each of these. The Conformance testing is of interest to me as I have been involved directly and indirectly with this for quite some years now. The book explains the process, standards required and submission of tests to GCF/PTCRB.

For those whom testing does not hold much charm, they can gain greater understanding of the concepts by reading Part II of the book. One thing I really liked in this book is that the diagrams explain the concepts very well. Rather than copying them straight from the 3GPP specifications, they have been improved and re-done by the author. Basic things like 'Dynamic TFCI selection' and 'Layer 2 transport channel processing flow for the 12.2 kbps RMC' are explained clearly using the diagrams.

There is just the right amount of detail in the chapters for Physical Layer, Layer 2 (MAC, RLC, PDCP) and Layer 3 (RRC, NAS). Further chapters show message flow sequence charts explaining things like 'setting up of speech call' and 'location updating procedure'. I have some basic sequence diagrams for message flow in the Tutorial section but the ones in the book are comparatively more detailed.

The book mainly covers UMTS, with an introduction to HSPA. It would be worthwhile to have the next edition covering LTE in detail. The main reason being that there are lots of changes in the case of LTE. The Air Interface has changed, the channels are different. The NAS messages and entities are different. UMTS (and HSPA) use TTCN-2 for testing but LTE uses TTCN-3. UMTS does not use MIMO (MIMO available for HSPA from Release 7 onwards) but LTE would generally always use MIMO.

Overall, this seems to be a useful book and I am looking forward to reading it in detail.

Golden-i: Futuristic Bluetooth Headset with Virtual PC Display

Microdisplay technology maker Kopin Corp. reports it has partnered with Motorola Inc. to introduce a wireless headset with a high-definition virtual display and speech recognition for remote control of things such as smart phones and PCs. Taunton-based Kopin (Nasdaq: KOPN) teamed up with Motorola’s Enterprise Mobility Solutions division to put a 15-inch virtual PC display together with a microphone and earpiece into the headset it calls the “Golden-i.” According to material from Kopin, the Golden-i uses Bluetooth 2.0 to connect to the devices, as well as to Bluetooth-enabled peripherals such as a mouse, touchscreen or keyboard. Golden-i runs on the Microsoft Windows Embedded CE 6.0 R2 operating system, and once connected, users will see their PC desktop screen on the 15-inch virtual display. To control the connected device hands-free, Kopin is incorporating the VoCon3200 software from Burlington-based Nuance Communications Inc. Golden-i also uses Nuance’s text-to-speech application to read back documents, e-mail messages, web content or any text on the display screen. According to Kopin officials, it supports up to 20 languages. If no interface peripheral such as a Bluetooth mouse is available, Golden-i can use its built-in Hillcrest Labs 6-axis, real-time position tracker to allow control of the connected device using head gestures. The device also provides a mini-USB port, and a removable Micro SD card slot taht can support up to 32GB of memory. The target market for Golden-i, according to Kopin, is remote workers looking to quickly connect to a PC or network for information, such as outside sales staff. It is also aimed at network support personnel, as it can support connections to multiple devices, Kopin said.Kopin, which counts the defense industry as a major customer, last December reported it had landed $3.1 million from the U.S. military for displays used in weapon sights. Once connected to a host device, such as a PC, users see their PC desktop screen on the 15-inch virtual display and with Nuance’s VoCon3200 software they can control it using voice commands in a number of languages. Kopin claims this software provides more than 90 percent proficiency straight out of the box, and the more it is used, the better it works. Golden-i requires no push-to-talk buttons and is ready to respond to a user’s request whether in light hibernation or during intermittent use. Golden-i also readily accepts conventional user interface from any host device touch screen, keyboard or wireless mouse and integrates Nuance text-to-speech, enabling Golden-i to read back any text displayed in a number of common languages. Running on the Windows Embedded CE 6.0 R2 platform, Golden-i can remotely wake a PC from practically any location and, when work is finished, the PC can be placed in hibernation with a single spoken command. The headset can also remotely control up to seven other devices or networks at one time, similar to the way users control software applications on a PC desktop. It operates much like a highly mobile server, a hub between various host devices. If a USB interface or removable memory is required, Golden-i provides a mini-USB port and a removable Micro SD card slot capable of supporting up to 32GB. Supported by Texas Instruments’ third generation OMAP dual processor platform, a single 1200 mA/hr li-ion battery should provide more than eight hours of standard use. While the Golden-i can be used just about anywhere, it is designed for “mobile information snacking”, rather than continuous use over long periods. Initial development of the unit has focused on industrial applications, so Kopin is seeking to engage several industrial organizations in several months of in-depth field testing and evaluation. Kopin hopes to incorporate any improvements and refinements uncovered during testing into its Golden-i products, which are expected to be available in 2010. Kopin believes Golden-i will free users from the need to carry a PC or laptop about with them. Freedom from work, though, is another matter entirely. You can read all about the hardware and software details and features of this device here.

Thursday, 14 May 2009

Inter symbol and inter carrier interference (ISI and ICI) in OFDMA

Radio channel are random, fast changing and error prone. In a wireless system the variation/fluctuation in the received signal is called fading. The goal of the wireless system design is to overcome different types fading and provide reliable and efficient transmission. Generally there are two types of fading.
  • Large scale fading: It is the fluctuation in the average signal strength over a large distance and is caused by terrestrial change. This occurs when a mobile travel from a lake to mountainous are to a lake area or from an open area to a tall buildings area. Large scale fading can be mitigated by controlling the transmit power.
  • Small scale fading: Occurs as a result of the fluctuations in the received signal strength over a small distance and is caused by multipath and Doppler's shift. Doppler shift refers to the change on frequency of the signal because of relative motion between the transmitter and the receiver.

The figure here shows the multipath propagation for a signal. Signal goes from transmitter to the receiver through multipath that have different lengths i.e. path 1, path2 and path 3. The signal from different path arrives at the receiver at different times although it’s originated from the same source. The received symbol as shown below is longer than the duration of the original symbol.

Delay spread can cause adjacent symbols to interfere at the receiver. As a result of the multipath the delayed version of the first symbol shifts into the next symbol time and thus causes overlap between he symbols. In OFDMA this is taken care of where more time is give for each symbol to be received at the receiver by inserting a guard time.

The Doppler shift introduces another type of interference in OFDMA i.e. inter carrier interference (ICI). OFDMA divided the spectrum into narrowband subcarriers and they are tightly spaced simply because they are orthogonal. One of the requirements for orthogonality is to maintain the subcarrier spacing exactly the reciprocal of the symbol period. The figure below shows the frequency shifts thus changing the subcarrier spacing which results in the loss of orthogonality. This loss of orthogonality creates interference among the signals which is called as ICI. Since the subcarriers in OFDMA are usually very narrow hence the OFDMA system becomes very sensitive to ICI. ICI destroys the orthogonality of the OFDMA system which is overcome by the use of cyclic prefix mechanism.

Under this mechanism OFDM symbols are extended into periodical symbols i.e. redundant information is sent out to ensure that analysis can be conducted on the undistorted information and is called as cyclic extension.

It can be implemented by copying the portion of the original symbol from the end and attaching it to the front or copying it from the front and attaching it to the end. Since OFDMA has already assigned the guard time to defeat ISI, cyclic extension can be put into the guard time interval. This is called cyclic prefix. With cyclic prefix used the delayed version of the previous symbols cannot shift into the useful time of the current symbol so ISI is eliminated as well. Also the cyclic prefix provides redundant information and allows spectral analysis in the receiver to maintain the orthogonality of the subcarriers. Thus the cyclic prefix can be used to deal with both ISI and ICI.

The above concepts can be summarized in teh form of the picture below


Vodafone (JIL) to release new APIs to third parties


Vodafone is set to announce a standard set of APIs, allowing third parties to create applications integrated with Vodafone servers around the world, including tapping the operator's billing system for micropayments.

It's also worth noting that these new APIs are coming out of the Joint Innovation Lab (JIL), so should be applicable to the other JIL members in time - adding Verizon and China Mobile would put the JIL in charge of applications provided to more than 700 million mobile-phone users.

Vodafone is unveiling a set of standard APIs that will work in every region in which the operator has a presence. This will allow developers to create applications and roll them out around the world, as long as they don't mind their market being limited to Vodafone's 289 million customers.

Operators have long allowed third parties access to internal services, particularly SMSC's for messaging and often with access to billing systems, too. But this has generally been on a case-by-case basis and only sharing limited functionality. Not only does that require developers to work with each operator in turn, but platforms are often fragmented even within the same operator - particularly where international expansion has been managed through acquisition - so developers often have to negotiate, and code, for every operator, in every region.

Not that today's announcement is the first attempt to address this problem: Vodafone makes much of the new API's ability to bill for small transactions, allowing developers to include the "insert coin to continue" functionality they've been hoping for. But Vodafone is also part of the "PayForIt" consortium, which provides the same functionality across multiple networks. PayForIt operates though gateways that take a cut of the money, so developers will have to decide on the value of being cross-network.

Obviously applications will need to be certified to have access to the APIs, something the JIL was already planning along with on-device APIs to allow (suitably signed) widgets with access to local, and network, resources - all of which should be revealed over the summer.

Wednesday, 13 May 2009

Surround Sound transmission technology from NTT DoCoMo


NTT DOCOMO, INC. announced that it has developed a highly efficient mobile spatial audio transmission technology that enables a mobile phone user to assign a spatial position to each sound source when listening to multiple sound sources, such as during a game or a conference call.

The technology enables a user listening with headphones to, for example, hear each speaker's voice as if it were coming from a unique direction, creating a virtual face-to-face communication environment.

DOCOMO, which is continuing to research and develop the technology for eventual commercialization, foresees applications including mobile conference calls, tele-education and online games.

While existing spatial audio transmission technologies independently process audio encoding/decoding and spatial audio synthesis, the new technology offers a more efficient method by integrating the two processes, thereby minimizing bitrate (or bandwidth) and computation loads suitable for mobile phones and other resource-limited devices.

The processes are collaboratively performed on both the server and client sides. The server identifies the important sound components of each speaker's voice, compresses them efficiently into a single stream and transmits it to the mobile phones. Each phone then decodes the received stream and simultaneously synthesizes spatial audio images

DOCOMO is demonstrating its new spatial audio transmission technology using docomo PRO series™ HT-01A handsets during Wireless Technology Park 2009 at Pacifico Yokohama on May 12 and 13.

Tuesday, 12 May 2009

iPhones in the War Zone



Tying the hands of a person who is speaking, the Arab proverb goes, is akin to "tying his tongue." Western soldiers in Iraq know how important gestures can be when communicating with locals. To close, open and close a fist means "light," but just opening a fist means "bomb." One soldier recently home from Iraq once tried to order an Iraqi man to lie down. To get his point across, the soldier had to demonstrate by stretching out in the dirt. Translation software could help, but what's the best way to make it available in the field?

The U.S. military in the past would give a soldier an electronic handheld device, made at great expense specially for the battlefield, with the latest software. But translation is only one of many software applications soldiers now need. The future of "networked warfare" requires each soldier to be linked electronically to other troops as well as to weapons systems and intelligence sources. Making sense of the reams of data from satellites, drones and ground sensors cries out for a handheld device that is both versatile and easy to use. With their intuitive interfaces, Apple devices—the iPod Touch and, to a lesser extent, the iPhone—are becoming the handhelds of choice.

The sheer versatility of the kit – with the capability of over 30,000 programmes – allows a huge variety of functions needed for operations ranging from providing language translations to the transmitting of sensitive information and working out trajectories for snipers. Projects are on the way to use them as guidance systems for bomb disposal robots and receivers of aerial footage from unmanned drone aircraft.

The US Marine Corps is funding an application that would allow soldiers to upload photographs of detained suspects, along with written reports, into a biometric database. The software would match faces, in theory making it easier to track suspects after they're released.

Members of the British military who have seen the Apple instruments in action drool about the opportunities on offer. The Ministry of Defence, however, remains wary of security implications and has "no plans" at present to go down the American path.

But Lieutenant Colonel Jim Ross, the director of the US Army's intelligence, electronic warfare and sensors operation, believes the iPod "may be all that the personnel need".

"What gives it added advantage is that a lot of them have their own personal ones so they are familiar with them," he said.

Another plus is the cost. The iPod touch (which soldiers can use over a secure WiFi network) retails for around $230 (£150) and the iPhone for $600. Bulk orders placed by the Pentagon bring further savings. The manufacture of a specific military model would be much more expensive.

Robert Emerson, a security analyst who has advised foreign governments on computerised warfare, said: "The US military has had a reputation for being somewhat heavy handed, with justice. But what they are doing with iPods and iPhones show they can also be nimble on their feet. Other militaries should learn to be equally open minded."