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.

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.

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.

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."

What actually are Smartphones?

Mobile industry is these days ruled by the word Smartphones. There is no doubt that 2008 was the year of the smartphone. The last 12 months has seen the launch of iconic devices such as the iPhone 3G, Google G1, Blackberry Storm and Nokia N97. Smartphones are by every means driving the mobile market.

I come across this term almost everyday and thought how actually we define a Smartphone or What is a Smartphone?

The word “Smartphone” is a newly minted term that is used to describe a Telephone-capable device that also provides information and data organization capabilities. They are similar in size, shape, and usage to normal cell phone but feature more extensive data organization software and web abilities. Smartphones are equipped with complete operating systems that determine what kinds of functions and applications are available for that device. They provide a convenient way to carry several hand-held digital devices in one body. They provide the data and contact organization of a PDA, connectivity of a cellular phone, along with advanced multimedia like access to email and can in most cases support web browsing.

What Can a Smartphone Do? Unlike traditional cell phones that restrict a user to the applications and features that are originally designed for and then fixed into the phone, Smartphones allow for significant user-customization. These full-fledged operating systems (of which there are several options to choose from) allow a user to customize, install, and configure applications to suit their individual needs. Along with the prerequisite phone capability, Smartphones typically perform all sorts of important and useful tasks.

Smartphones are very smart in personal Information Management (PIM): PIM is a whole category of software functions that organize personal information. A typical PIM suite includes a scheduler for events, and address book for contacts, and to-do list. PIM can also include email, text notes, voice notes, and alarms / reminders.

Syncing with Desktop and Laptop PCs: Many Smartphones are designed to communicate with full-fledged PCs. Aside from just being cool, this feature allows users to easily install, remove, change and configure the software that they choose to equip their Smartphone with. It also allows further synchronization with PIM software both on your phone and on your PC.

Instant Messaging (IM): Not every phone that provides IM capability is a smart phone. But almost every Smartphone has a keyboard that at least allows access to every letter of the alphabet for sending Text messages. Some Smartphones have a key for every letter; others designate several letters per key. Word recognition software and other smart features further improve the speed and accuracy of Text messaging on these kinds of phones.

Email Access: While there are plenty of non-Smartphones that provide internet and email access, this option is more complete (and configurable) on Smartphone devices. You can sync email with your PIM software both on your phone and on your PC, send, read, and organize email, all from your phone. In most cases, you won’t even need to be near a wireless hotspot, either.

Web Browsing: All Smartphones allow for some form of Internet access. Wireless Network Protocols, or the technique in which web information is sent and received over cellular networks, are grouped into different generations.

But the question which remains albeit is what Makes a Smartphone Smart?

Smartphones are capable of so many features normally reserved for the realms of PCs and powerful PDA devices because they are almost PCs and PDAs themselves. There are typically two schools of thought used when designing a Smartphone: Create a PDA with Telephone capabilities, or a Telephone with PDA capabilities. No matter what design elements went into Smartphones developmental stages, there are still two things that set these mobile wonders apart from their regular cellphone cousins.

As mentioned above a Smartphone differs from a regular phone in that it has a processor running inside it, much like a computer does. These processors are currently nowhere near the power of PCs, but with the advent and subsequent redesign of Ultra Portable PCs (sometimes called Micro PCs), we are sure to see great leaps in Smartphone speeds in the future. Current Smartphones commonly use ARM processors; a power-efficient design used in other devices like routers, printers, and advanced MP3 players. A Smartphone processor is aided by computer chips that help perform certain tasks. A Smartphone equipped with a Digital Camera has an Image Processing Sensor inside it, much like a regular digital camera. Features like Playing Digital Music, complex web browsing, and other such access smart functions are all made possible by these computer chips.

If Smartphones have Operating Systems (OS), then it stands to reason that they also have software applications, as well. Applications that are written for a specific Smartphone platform (Platform is a fancy reference to the OS) can run on a Smartphone with that particular platform, regardless of what manufacturer produces the phone.

Based on the above discussion there is no doubt the most important software on a Smartphone is the Operating System. This is because nothing will work without it. A Smartphone operating system manages the hardware and software on the device. Some OS cover the entire access Software Stack while others only provide the lower levels like the Kernel and Middleware. These OS versions rely on third party software platforms to provide User Interface Frameworks.There are several different Operating Systems available for Smartphones. Some are designed for manufacturer-specific Smartphones, others are open and can be used on any Smartphone that meets the minimum requirements. Following are some of the OS for the Smartphones.

• Symbian OS: Symbian OS is used in over 100 different makes and models of Smartphone. This Operating System contains only the Kernel and Middleware parts of its software stack. This means that users of the Symbian OS will rely upon other software platforms for the AEE and User Interface Frameworks. This allows significant customization by both Wireless retailers and consumers.
• Linux OS: There is something special about Linux. It is developed and written by the developer community rather than by a single company. This allows for maximum creativity and innovation for developers and those software-savvy consumers, but has one major drawback: it means that software, updates, and other applications written for Linux operating systems differ greatly from each other. This reduces compatibility, and thus originally caused developers to avoid Linux. That is now changing, but many Smartphone manufacturers prefer to stick with more universally accepted OS software.
• Windows Mobile: This is one of the few Smartphone OS that envelops the entire Software Stack. Much of the strengths of Windows mobile lie in its completeness and full compatibility with other Windows based systems.
• Java and Garnet OS

See also: Dumbphones, Featurephones, Smartphones, Superphones...

LTE-Advanced Presentations and White Papers

I have added some LTE-Advanced presentations and White papers to the 3G4G website. If interested, here is the link.

Powerful search functionality on 3G4G website

I just figured out yesterday that Google now allows to do very powerful customised searches. I have added a search box to the 3G4G website. Try it out (bottom of the page) for any 3G/4G or Mobile related searches here.

Bluetooth yet to become popular in Japan

Plen: The Bluetooth Controlled Robot

Interesting article from the Recent Signature Magazine:

Tokyo is the high-tech capital of a gadget-loving country. And yet, “consumer awareness and acceptance of Bluetooth technology has lagged in Japan,” according to Emma Naudo, an analyst at IMS Research, a U.K.-based firm that publishes an annual report on the subject.

Derek Soh is the Bluetooth SIG’s marketing director for APAC and Japan. He agrees with Naudo’s assessment, noting a Millward Brown study that showed only 60 percent of the Japanese population is aware of the technology, versus up to 85 percent elsewhere. This is puzzling, given that Japan has so many companies developing and pushing the technology. According to Soh, among companies represented in the Bluetooth SIG, Japan has the third-highest number of Bluetooth SIG Associate members after the United States and Taiwan, and it boasts the fourth-highest number of Adopter members.

So why is Bluetooth technology under performing in a land that is often the first to embrace the latest technology?

“Headset-to-handset connection has been Bluetooth technology’s biggest driver in handsets,” says Alex Green, also of IMS Research. “So if the headset market hasn’t taken off in Japan, it’s going to reduce the demand for Bluetooth in handsets.”

In Europe and the United States, concerns about the health effects of cellphone usage and laws against using mobile handsets while driving fueled the proliferation of wireless headsets. However,in Japan people tend to spend less time driving and more time taking public transit. There is also a cultural preference for mobile text messaging over making voice calls. While the Japanese government enacted stiffer penalties in 2004 for driving while talking on a cell phone, the uptick in Bluetooth enabled headset sales has been modest. “Headsets just don’t appear to be available in as many retail outlets as in other countries,” says Green.

According to Mihoko Kasuga, an executive with SoftBank Mobile, the nation’s third-largest and fastest growing mobile phone service provider, Japanese consumers see Bluetooth technology more as an added bonus than an essential feature. For transferring data, infrared comes standard on most handsets and is the preferred method of quickly exchanging contact details. Mobile phones also have dedicated e-mail addresses, and Japan’s high-speed 3G networks facilitate data transmission.

But there is light on the horizon. “The number of Bluetooth enabled handsets in Japan is forecast to grow from just under 20 million—30 to 40 percent of those shipped—in 2007 to over 60 million, 80 percent, in 2013, a CAGR (compound annual growth rate) of 24 percent,” says Naudo.

In addition to more headset use, there are other reasons for the optimistic forecast. “Streaming music services over mobile networks, such as Japan’s Chaku Uta, will be key drivers of Bluetooth inclusion in cellular handsets,” predicts Andy Bae, a senior analyst at New York-based ABI Research.

Bluetooth technology is making inroads in several other Japanese sectors as well. The auto industry is installing the wireless specification in more and more new cars. “Japanese automakers have lagged behind their European and U.S. counterparts in adopting Bluetooth technology, but now they are beginning to catchup,” noted an article in The Nikkei Weekly, a business newspaper published in Tokyo.

Says Green at IMS Research, “We estimate that around 24 million Bluetooth chips were used by automotive companies in 2007,” although he added that “only around 10 percent of cars produced in 2007 had Bluetooth technology built in at the point of production.” That has opened up a new market for after market products like hands-free kits, navigation devices and A/V systems.

Another sector where Bluetooth technology may see further success in Japan is video games. “In 2007, total shipment volume of Bluetooth enabled gaming devices such as the Nintendo Wii and Sony PS3 surpassed that of Bluetooth enabled headsets – amazing!” says Soh.

Finally, several companies, including Toshiba, will begin rolling out Bluetooth low energy enabled devices aspart of a personal health care ecosystem by mid-2009, and many hope this effort will help familiarize Japanese consumers with the technology. (Click here for more on Toshiba and the Japanese health care market.)

With the ongoing updates to the Bluetooth core specification, developers are planning plenty of newproducts featuring the technology. Whether Japanese consumers will bite remains to be seen.

Beau Miller has lived in Tokyo for 17 years and is the editor of Metropolis, Japan’s weekly lifestyle and listings magazine for the English-speaking community.