What is this MEMS and why is it required for 4G?

The mobile technology evolving at an amazing speed going from 3G to 3.5G in around 5 years and now going from 3.5G to 4G in less than 5 years. According to Analysis, Annual Global Mobile Handset Shipments to Reach 1.5 Billion in 2011. Converged-function handsets will become a mainstream product with more than 30% share in developed markets by 2011. There is a constant pressure on the handset manufacturers to reduce the power consumption and the chipset size and at the same time driving down the cost of the device.

RF micro-electro-mechanical systems (RF-MEMS) is a semiconductor technology that allows micro-scale moving mechanical devices to be integrated with electrical transistors on silicon wafers. RF-MEMS technology can be utilized to make high-frequency components whose RF characteristics can be adjusted during operation, allowing for the first time reconfiguration of radio hardware under software control. The ability to reconfigure operating characteristics in real time results in a substantial reduction in the required number of discrete components for a given set of functions, significantly relieving pressure on the handset product developer.

While the electronics are fabricated using integrated circuit (IC) process sequences (e.g., CMOS, Bipolar, or BICMOS processes), the micromechanical components are fabricated using compatible "micromachining" processes that selectively etch away parts of the silicon wafer or add new structural layers to form the mechanical and electromechanical devices.

An early micromotor built in the SUMMiT technology. For size comparison a microscopic dust mite is shown on top.

There are several different broad categories of MEMS technologies:

• Bulk Micromachining
• Surface Micromachining
• LIGA
• Deep Reactive Ion Etching
• Integrated MEMS Technologies

Details available here.

MEMS is not really a new technology. It has been around since 1960's but only recently it has become feasible. Samsung watch phone was the first phone to have a commercial MEMS circuit and its being used in variety of devices nowadays, not just mobiles. For those who watched the opening ceremony of 2008 Beijing olympics would have seen the different coloured torch display. That 'Waving Torch' used MEMS circuitry.

Scientists are also working on making MEMS intelligent and they are looking at microorganisms for ideas. The integration of microorganisms with MEMS, resulting in “biotic-MEMS,” is a hot topic for scientists designing micron-level machines. Recently, researcher Xiaorong Xiong of Intel, microbiologist Mary Lidstrom, and electrical engineer Babak Parviz (both of the University of Washington) have catalogued a large number of the most promising microorganisms for different areas of MEMS systems. They show that many of these microorganisms can offer capabilities beyond the limits of conventional MEMS technology.

Finally, from EE Times:

French research and strategy consulting company Yole Dveloppement (Lyon, France) provides an analysis on MEMS components for cell phone applications as it expects this market will represent $2.5 billion in 2012. In its latest report, entitled MEMS for Cell Phones, Yole stated that the cell phone industry represents a complex challenge for MEMS but also its greatest opportunity for growth in the next five years.

According to the market research firm, silicon microphones and FBAR/BAW filters have experienced "incredible growth" since their introduction in 2003 and are now entering the maturity stage. MEMS accelerometers are in "a strong development stage", and MEMS products such as gyroscope, microdisplay, micro autofocus and micro zoom are at the emerging stage.

Yole also mentioned products that are not yet in the emerging stage. Among them are pressure sensors, micromirror, RF switch/varicaps, oscillators, and micro-fuel cells.

Yole reported that, for the year 2007, cumulative sales reached $440 million for three MEMS products in cell phone applications, namely silicon microphones, FBAR/BAW filters and accelerometers.

As a conclusion, Yole said it anticipates MEMS will become a key driver for innovation in the cell phone industry, and new cell phone features will represent 60 percent of the total MEMS market by 2012.

Interested people can also read:

RF-MEMS for Wireless Communications, Jeffrey L. Hilbert, WiSpry, Inc. - IEEE Communications Magazine • August 2008

IMS: Reality check

IMS is another technology not doing too well at present. I came across this report by Yankee group, "IMS Market Update: The Honeymoon Is Over, Now What?" and it answers some of the questions why IMS is not as popular as people expected it to be 3-4 years back.

Some of the promises made by IMS were:

• New IMS based apps, hence increased ARPU
• Simplified network design, hence lower OPEX
• Platform for killer services
• Components interchangeable
• Plug and Play environment for access networks

But the reason IMS has not found success is because:

• IMS Standards are in flux
• Everything is quite complex and not very clear
• OSS/BSS integration is very complicated

An article in Cable 360 has some up to date market details:

Based on a report completed in January by ABI Research, Ericsson is market leader in providing IMS infrastructure followed by Alcatel-Lucent and Nokia Siemens. The other vendors in this ranking include Motorola (4), Huawei Technologies (5), Cisco Systems (6), Nortel Networks (7), Acme Packet (8), Thomson (9) and Tekelec (10).

Bundling is increasingly the way that IMS is sold. "Huawei combined a lot of their wireless offerings with IMS," ABI Senior Research Analyst, Nadine Manjaro said. "Whatever their contacts were, they had an IMS element."

"Previously (IMS) was more fixed," she said. "IMS is difficult to integrate. (So) one trend is combining IMS with infrastructure and 3G deployment and managed services," she said.
Increasingly critical to versions 6, 7 and 8 of the Third Generation Partnership Project (3GPP), IMS will become more tightly linked with mobile technologies, Manjaro predicted. The overall context remains telephony-focused.

"You see highly voice-over-IP related deployments of IMS globally," she said.

My understanding is that with the tight squeeze on financial market, everyone is trying to spend as less as they can. This means that end users are being shy of the extra features and services as long as it costs them and the operators are being shy of investing in new technologies or upgrading their infrastructure. Even though investment on IMS could be significant, it can provide long term benefits which may distinguish an operator from others and provide the cutting edge.

Another thing is that the IMS technologists (and why just them, others as well) should ensure that all the technical problems are ironed out and start promoting the technology to everyone. People ae already confused enough about HSDPA and 4G and we need to prepare them to look forward to IMS.

Mobile Tv going in Hibernation!

Earlier this month, there was this report which mentioned that 'Mobile 3.0' (a consortium in Germany) decided to end plans to launch a DVB-H (handheld) network. The failure was blamed to some extent on the wireless service providers who were not abole to get their act together to establish a paid DVB-H infrastructure.

The following is an extract from the article:

Burda and Holtzbrink, both publishing houses, and South African media company Naspers have thrown in the towel and won't launch a DVB-H network in Europe, the reports said.

Their effort wasn't helped when service providers said they plan to introduce mobile TV devices that use the free DVB-T technology. Noting that subscribers aren't likely to favor the idea of paying for TV on top of their often hefty wireless charges, service provider Vodafone has said it favors a mobile TV strategy whereby consumers pay for add-on video services that are offered in conjunction with free mobile TV. Mobile 3.0 had planned to charge monthly fees of as much as $10 to $15.

The Mobile 3.0 group had begun testing a service with nine TV channels and three radio stations.

The German situation isn't likely to influence the delivery of mobile TV in the United States, which is still in its embryonic stage. To date, no major third-party providers of mobile TV have emrged in the United States.

According to a report in Mobile burn the same day as the above news:

Toshiba announced that it was shutting down Mobile Broadcasting Corp. at the end of March 2009, stating that the company has not gained enough subscribers due in large part to the popularity of the free TV broadcasting that many of Japan's phones are now capable of receiving (and even recording).

The situation is different on many levels in the U.S. The nation's two largest carriers, AT&T and Verizon Wireless, both use Qualcomm's MediaFLO (definition) mobile TV standard on their TV compatible cell phones. While different technically, MediaFLO and DVB-H work on the same basic premiss of broadcasting a separate, mobile optimized digital TV signal over the air that compatible devices can receive. Since AT&T and Verizon more or less control the handset models that are available to its customers, much as is the case with German carriers, the two have been able to steer subscribers into using the MediaFLO system while avoiding competition from devices that could otherwise pick up free broadcast TV signals. Similarly, Sprint offers a streaming TV service on most of its handsets. T-Mobile currently offers no integrated TV support to its customers.

Then we had the bad news about Mobile Tv in Korea:

Some new numbers on mobile TV's non-pickup in Korea...more specifically, the TV broadcasting using digital multimedia broadcasting (DMB) format. The story says DMB, which includes the free terrestrial and premium satellite DMB-- has an audience of some 13.7 million, according to latest data. That's up from nine million in December last year. The number of DMB-enabled receivers sold here reached 13.69 million in June.

-- Mobile phones accounted for 48.4 percent of all DMB subscribers.-- Car navigation systems and other DMB-enabled terminals used in vehicles accounted for 37.8 percent of DMB receivers, followed by portable media players at 9.4 percent and USB devices at 3.8 percent.?Laptop computers were the least popular DMB device, accounting for just 0.9 percent of all receivers.

Bu the overall viewership numbers remain minuscule: TNS Media, a local research firm, overall viewer rating for the day was just 1.172 percent, peaking at 3.585 percent during the commuting hours of 6 to 7 p.m. in the survey. And, even more surprising: male viewers in their 50s proved the largest audience for mobile TV rather than the convention wisdow that tech-savvy youngsters would be watching TV on the go. Viewership was also relatively high among men in their 40s and 30s, but minuscule among women and younger customers.

We have completely stopped hearing anything new on MBMS. There is no news on Mobile TV trials. I think that Mobile Tv is going in Hibernation and will be for some time, until some killer charging models are in place for these kinds of services.

Is WiMax Slowing Down

In the past few week it’s becoming quite interesting to know where WiMax is heading and it’s progress if at all there is any. There are so many articles which emerge everyday to say that WiMax has leaped further in terms of development in the technology and commercialization. Although I am too convinced about that but one thing about which am pity sure is that LTE has to seriously push its plans if it has to be in any sort of chance to catch WiMax.

There is no doubt that WiMax, a high-speed wireless service, is gaining momentum worldwide. Latest figures show WiMax equipment sales rose nearly 50 percent in 2007 to US$800 million. WiMAX networks have been deployed in some 80 countries with 2.2 million customers, and growth is expected to continue.

According to the WiMAX Forum, worldwide WiMAX customers will exceed 200 million by 2012, generating US$7.7 billion in equipment sales. With IEEE 802.16 ratified by the ITU last October, many operators see it as a sensible alternative to 3G mobile Internet service.
Although there is a significant divide between the equipment manufacturers when it comes to LTE and WiMax but the later is certainly pushing hard thus making life very difficult for LTE camp. Indian government’s decision of auctioning 2.3, 2.5 GHz frequency bands for broadband data has further encouraged WiMax camp.

So far, most of the excitement has been generated by equipment manufacturers such as Huawei Technologies, a member of the WiMAX Forum. Huawei is moving fast to take advantage of surging demand, mostly in Europe and North America. So far Huawei has sold 16 commercial networks and 30 trial networks, making it one of the most prolific WiMAX vendors in the world.

Huawei also is engaged heavily in WiMAX R&D activity: It has 1,200 engineers dedicated to WiMAX product development; it owns 100 WiMAX- related patents, more than any other company. Huawei is also developing WiMAX terminals which are expected to become available for sale later this year. The handsets reportedly will work in dual-mode with CDMA, GSM and 3G (WCDMA).

ZTE, another Chinese equipment maker and a senior member of the WiMAX Forum, began OFDM research in 1998. It projects sales of WiMAX equipment will reach that of CDMA by 2011 (estimated US$700 million). ZTE is more enthusiastic about WiMAX and it predicts WiMAX will make up 20 percent of the global wireless market by the end of 2009 after commercial handsets become readily available later this year.

When all the manufacturers are getting excited and trying to run as fast as they can operators are mum whether they will jump on the WiMAX bandwagon. Vodafone, T-Mobile and AT&T are yet to announce any significant trials on WiMax. There are no signs of any massive deployment of WiMax especially in China and India which are considered as the biggest WiMax market. China Mobile and China Unicom show no signs of massive deployment or commercial service after small trials two years ago in a half-dozen cities, including Beijing, Shanghai, Wuhan and Shenzhen. Most trials employed 802.16d (fixed access) at 3.5 GHz, a temporary spectrum band for experiment. Most trials used WiMAX as backhaul for businesses to transmit data and video in a campus environment. It is premature to assume large-scale deployment will follow, at least in the immediate future, because the industry is consumed completely by restructuring, which, in addition to changes in organization and personnel.

China Mobile, for example, is carrying the torch of TD-SCDMA, a home- grown, 3G wireless standard which the government hopes to become a winner someday. For China Mobile, TD-SCDMA is very much a political mandate and it has no option but to succeed. If this holds out, it is natural for the operator to adopt some kind of LTE for TD-SCDMA, an evolutionary platform for faster speed and more profitable service.

Questions remain, Operators must weigh WiMax’s potential gains against the cost of deploying regional or national networks, and there is no clear-cut answer. While WiMAX can offer significant speed to fixed and mobile devices which are conducive to more bandwidth-sensitive services like video and TV broadcast, the key hurdle is scale. As tests show, a typical 802.16e base station delivers 30Mbps, but actual speed can whittle down to 1.2Mbps or lower when “fully loaded” with access.

If speed is compromised, cost will become a serious concern. According to estimates, operator capex for WiMAX will be 20 percent to 50 percent higher than for HSDPA, a software-enabled overlay for sending data over 3G networks. At higher frequency, say 3.5 GHz, the number of WiMAX base stations must increase, as many as 50 percent more than for HSDPA, to cover the same area without signal degradation. This is the last thing operators want after already plunking down billions on 3G networks.

So far operators have focused mainly on network and handset performance and not on services which can have a negative effect on initial growth. Despite all the hype, it is not clear if WiMAX will create the miracle equipment vendors want to see especially in China, since there simply is a lack of driving force among the governments, operators and the public. If anything, WiMAX will complement 3G especially in data service for high- end customers, enterprises and government agencies, but its role as a public service will be limited.

Q2 Revenues for the major Telecomms Companies

With the Quarter 2 (Q2) just gone everybody concerned in the telecoms industry are waiting for the Q2 results from the major telecoms giants. By looking at the current state of the economy and with the entire credit crunch problem, there is some nervousness regarding the growth expectation in the telecoms area.

In the past few weeks most of the telecoms giants has announced their Q2 earning. I must say the results don’t look too bad and I will not be quoted wrong when I say that some of the investors have breathed a sigh of relief. There is no doubt that little bit of tricky times might be head but overall growth forecast for Q3 are encouraging.

First of all let me tell you about the major shock of the Q2.

Ericsson and Alcatel-Lucent has really got lot to do after their Q2 results. Although expected, Swedish telecoms giant Ericsson reported a fall of 70 per cent in its second quarter profits. The company blamed the fall on the high cost of shedding staff and falling handset sales by its Sony Ericsson joint venture. Sony Ericsson reported that its second quarter pretax profits were 8 million euros compared with 327 million euros a year earlier and announced plans to cut 2000 jobs worldwide.

But Alcatel-Lucent was the most shocking when it announced a humongous $1.7 billion second quarter loss. CEO Patrica Russo and chairman Serge Tchuruk who together orchestrated AlcaLu’s merger two years ago has already said that they’ll step down by year’s end.

The size of the loss, the sixth straight quarterly red ink since the merger has stunned analysts who had expected less painful news. The company said $1.27 billion of the loss was due to a write-down of AlcaLu’s North America CDMA technology business.

The company also is trimming its board, dumping former Lucent CEO Henry Schacht.

I must admit that as one of the giants of telecoms world the above results looks very disappointing. What is more worrying specially for Ericsson is the fact that it’s sales in Western, Central and Eastern Europe, the Middle East, Africa and Asia Pacific were all down by varying degrees. The only positive news came form America where its sales in North and Latin America were up.

TeliSonera on the other hand reported a 5.7 percent increase in sales for the second quarter and revenues of $1.3 billion, up some 6 percent from a year ago. TeliaSonera said it expects stable growth for the remainder of 2008 which is indeed good news for the investors.
The Nordic telco, which spurned an attempted takeover earlier this year by France Telecom said margins for broadband services in Sweden were under pressure, hurt by the growth of mobile broadband services. CEO Lars Nyberg told Swedish radio news that he backed the board's earlier decision to reject a bid from France Telecom."I am glad that we can continue to grow on our own," Nyberg said.TeliaSonera and its associated companies had some 122.9 million customers in the quarter, up 19.3 per cent from the end of the second quarter 2007.

First look at AT&T's earnings for Q2 showed that perhaps we did not have to worry about big, old AT&T after all. Many industry analysts had been watching the telco's second quarter numbers for signs of weakness that might portend further weakness for the industry at large, but AT&T issued a report marked by an increase in net income, strong wireless performance and continued progress with U-verse and wireline IP efforts.
For the second quarter, the company's net income hit $3.8 billion, or $0.63 earnings per share, up 34 percent from the same quarter last year. Revenue reached $30.9 billion, an increase of 4.7 percent. Wireless data revenues were up 52 percent, and wireless postpaid subscriber churn came in at 1.1 percent, a quarterly record for AT&T. Wireline IP data revenues increased 16.1 percent. U-verse subscriber additions amounted to 179,000 for the quarter, giving AT&T a total U-verse subscriber tally of 549,000.

There are good results from Vodafone as well. I have always been impressed with Vodafone as a company. Vodafone has always got ideas in its sleeve and it always come with some aggression and beat the general trends in the market. The Q2 results of Vodafone were again boosted mainly by the emerging markets where the only big disappointment came form Spain.
Some of you might remember, recently when Vodafone announced that it would feel the effects of the global downturn, its share price went down by 14 per cent, the largest fall in Vodafone history.

The company reacted to this fall by announcing a £1 billion buyback. However, this warning by the outgoing CEO, Arun Sarin, that the outlook was less than rosy might have disguised some hidden gems within Vodafone's arsenal of revenue generating resources.
Sure, the sharp decline in the Spanish market hit the company badly as did the lacklustre results from the U.K. But both are very mature markets and consumers in both countries are reining back on all expenditures. The revenue growth high spots were the emerging markets, namely Eastern Europe, the Middle East, Africa, Asia and Pacific which was up 30.9 per cent, supported by growth from India of more than 50 per cent. Overall, Vodafone reported a 19.1 per cent revenue growth to £9.8 billion for the three months to the end of June 2008-and added 8.5 million subscribers.
I always like the aggressiveness that Vodafone has got when it comes to revenue generation. This was once again proved evidently when Vodafone announced the 50 per cent rise in Q2 revenues from its data services. This shocking 50% rise is after the number of its customers using the web from mobile devices was more than doubled. Data revenue for the quarter stood at £664 million globally, compared with £441 million for the same period last year. The CEO of Vodafone Germany, Friedrich Joussen, was also upbeat claiming that, although revenue fell slightly in the second quarter, due mainly to regulatory causes, "it won't be long until we see growth again."
There are also growing indications that the company is seriously considering an offer for freenet's DSL business. "We are taking a very close look at it," said Joussen, adding that a purchase couldn't be ruled out. Vodafone Germany doesn't necessarily need acquisitions as its organic growth is strong, Joussen said.

Nokia also posted better that expected results for Q2 after having previously forecast that the cell phone market would grow by 10 per cent. The CFO of Nokia, Rick Simonson, has indicated that, with half a year visibility, Nokia would be able to post growth of 10 per cent or more. This upbeat assessment comes after the company good results for the second quarter which pushed Nokia's share price up by eight per cent--albeit that the company's share price had plunged about 40 per cent this year amid concerns the mobile industry would suffer as the credit crunch and inflation took their toll.

There is no doubt that everybody's affected by the economic reality and Nokia and its customers are no different. But in my view Nokia have an ability to play all markets where some markets are growing strongly, some not so strongly. That is the beauty of Nokia where it’s not trapped to one market only.

During the posting of the Q2 results, Nokia's CEO, Olli-Pekka Kallasvuo, added to Nokia’s optimistic outlook by stating that the company had received good feedback about the broad range of new products it expected to sell in its handset business. Last week, Nokia indicated that increased demand from Russia and India would help it achieve continued growth this year.
LG Electronics is forecasting a tough third quarter despite posting positive results for the second quarter. The handset vendor said it is facing slowing shipments to emerging markets and higher competition in developed markets.

The handset maker, which ranks fourth in the handset market in terms of global shipments, said revenues grew 39 percent from the year-ago quarter to $3.7 billion, which was more than one-third of the parent company's revenue in the second quarter. The division reported an operating profit of $531 million, up nearly 12 percent over the year-ago quarter.

By looking at the above Q2 results I feel highly optimistic for good times ahead. Verizon Communications support my view further when it announced its second quarter earnings rose 12 percent, galvanized by 45.3 percent year-over-year wireless data growth. Verizon Wireless added 1.5 million net customers in Q2, bringing its overall subscriber total to 68.7 million.

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:

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.

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.

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.