ABOUT MOBILE TV
Television? No good will come of this device. The word is half Greek and half Latin.
—C. P. Scott, journalist
For the first time in the history of the Emmy awards, in 2006 a category was created to give awards for original production of content that is designed for the new platforms, including PCs and the mobile world—cell phones, PDAs, Palm devices, iPods, and mobile TV. More than 74 entries were received, more than for any other Emmy award category. The entries included “24 Mobisodes” from the leading Hollywood studio 20th Century Fox. In October 2006, the content industry’s biggest event, MIPCON 2006, described the mobile TV as the most significant wireless trend ever for the mobile industry in the coming years. The production of content for the tiny screens of mobile TVs and PDAs has indeed unleashed the imagination of the industry with the production of short-form programs and original content designed to be effective even for the limited span of time available for viewing.
When the FIFA 2006 games kicked off in Germany in June 2006, the towering TV transmitters of Berlin, Munich, Frankfurt, Rome, and Milan, as well as a number of other European cities, broadcast the matches live for mobile TV for the first time in the 76-year history of FIFA. Some of the broadcasts were in fact for a wide range of devices, from mobiles with screens no larger than 2.5 in. to standard- and high-definition TVs, giant screens and wall displays, theaters, and ship-borne terminals. The broadcasts involved multiple technologies for mobile TV, such as digital video broadcasting for handhelds (DVB-H), digital multimedia broadcasting for TV (DMB-T), DVB-T, and analog TV, in simultaneous transmissions. At the same time thousands of 3G cellular towers were broadcasting and streaming TV to viewers traveling in cars and trains across Europe and other parts of the world. Transmissions were going out to tiny mobile screens that flickered on the mobile sets to bring a new TV experience to their users. The world of digital television had graduated to a new stage. After multiple trials and some commercial launches, the world of mobile TV had finally arrived.
While many were watching the transmissions live, special 1- to 2-min bulletins and broadcasts were going out live from the studios of news and business wire companies, which were designed to let mobile phone users watch and be in touch with their favorite events even though their activities would not allow them to be physically present at the site. The live transmissions were a “follow on” action after a series of successful trials in Pittsburgh, Barcelona, Oxford, and other sites that proved they could bring digital video broadcasting to millions of hand-helds under a new technology. This technology, which has been termed digital video broadcasting for handhelds, was an extension of the digital terrestrial technology or DVB-T being deployed widely across the globe.
At the same time chip makers like Texas Instruments, which in 2004 had brought out the TI Hollywood chip, a single chip for DVB-H tuning and reception in mobile sets; DiBcom; and other manufacturers were watching with their single-chip DVB-H embedded receivers the performance delivered by the high-efficiency and high-processor-power designs, which were rendering each frame of the match in real time and delivering quality TV that could not have been imagined even 5 years before.
These DVB-H transmissions that brought the FIFA World Cup live were not the first transmissions for mobile TV. The 3G operators in the United States of America, Japan, and Europe had been offering streaming video services and live TV since the commissioning of their 3G networks. Telenor Norway, for example, had broadcast the 2005 Winter Olympics held in Torino live, along with the highlights and other features, for mobile users on 3G networks. The same content was brought live to the users of 3G networks in Australia by Operator 3, and the 3G operators have never looked back. The 3G services are interactive in nature, as each user who chooses to watch his selected program starts his own Internet Protocol (IP) stream over the networks.
Elsewhere in the world, operators were using different technologies for delivering mobile TV and multimedia services. In Korea services using digital multimedia broadcasting technologies began in 2005, and in Japan the 3G FOMA services, in 2002, began the plank that would support the 3G mobile TV services in addition to the 1-Seg ISDB-T, based on terrestrial transmission, which came in later in 2006.
Mobile TV is now a reality. The technology, though new, has been proven. It is inconceivable that major global events or news will not now be available on the mobile TV medium, as will future major entertainments, sports, or other national or international events. Operators have started gearing up their networks for adding mobile TV services or have rolled out entirely new networks. There are over two billion mobile users around the globe and the potential market for mobile TV will be over 500 million by the end of 2007. The growth in the market is expected to be exponential and it will be aided by the lowering price of handsets and better agreement of standards. The price of chip sets for mobile TV has already fallen below the $10 price point, opening the way for advanced handsets to be widely available. The price points of the chip sets are expected to fall below $5 by the end of 2007.
Mobile TV is the transmission of TV programs or video for a range of wireless devices ranging from mobile TV-capable phones to PDAs and wireless multimedia devices. The programs can be transmitted in a broadcast mode to every viewer in a coverage area or be unicast so as to be delivered to a user on demand. They can also be multicast to a group of users. The broadcast transmissions can be via the terrestrial medium just as analog or digital TV is delivered to our homes, or they can be delivered via high-powered satellites directly to mobiles. The transmissions can also be delivered over the Web using the Internet as the delivery mechanism.
1.3 HOW IS MOBILE TV DIFFERENT FROM ORDINARY TERRESTRIAL OR SATELLITE TV?
Mobile phones constitute an entirely different world. The phones come with screens that are tiny in comparison to a standard TV. They have a limitation on power consumption as preservation of the battery and talk time is of paramount importance. Every device in the cell is designed with features that can conserve power. The processors in cells, though powerful even in comparison to PCs just a few years back, cannot be harnessed to run complicated encoding or decoding tasks or format and frame rate conversions. Cell phones are connected via the 3G cellular networks, which can support high data rates for multimedia but are not designed to handle the 4–5 Mbps needed for a standard definition TV. Hence, though there are cell phones that can receive ordinary TV telecasts, they are not really ideal for such use.
Mobile TV is a technology that has been specifically designed to fit into the mobile world of limited bandwidth and power and small screens and yet add on new features such as interactivity via the cellular network. Taking advantage of the small screen size the number of pixels that need to be transmitted is reduced to roughly one-fourth of a standard definition TV. Digital TV today is based on the use of MPEG-2 compression mainly because this was the best compression available in 1990s when widespread cable- and satellite-delivered TV became common. Mobile TV uses more efficient compression algorithms such as MPEG-4 or Windows Media for compressing video and audio and that too with visual simple profiles. Compressing audio efficiently for voice has been the hallmark of cellular networks and these technologies are carried forward in the mobile TV world with the use of audio coding in adaptive multirate, QCELP, or advanced audio coding based on MPEG-2 or MPEG-4. In the Third Generation (3G) world, which is characterized by the need to use bandwidth efficiently to accommodate thousands of users in a cell area, file formats based on cellular industry standards such as 3GPP (Third Generation Partnership Project) are commonly used. In order to reduce bandwidth further and based on transmission conditions, cellular networks may also reduce the frame rates or render frames with a lower number of bytes per frame.
However, reducing the bit rates needed to deliver video is not the only characteristic of mobile TV services. The broadcast technologies have been specially modified to enable the receivers to save power. DVB-H for example uses a technique called time slicing, which allows the receiver to switch off power to the tuner for up to 80% of the time while showing uninterrupted video. The transmissions also incorporate features to overcome the highly unpredictable signal reception in mobile environments by providing robust forward error correction. Mobile environments are also characterized by users traveling at high speeds, e.g., in cars or trains. Standard terrestrial transmissions based on Advanced Television Systems Committee (ATSC) or even DVB-T standards are not suited to such environments due to Doppler shift of the frequencies, so that the 8000 carriers that are used for coded orthogonal frequency division multiplexing (COFDM) modulation appear to be at frequencies different from the intended. For these purposes, special modulation techniques such as COFDM with 4K carriers are used. Mobile TV has spawned its own set of standards for terrestrial, satellite, and 3G cellular network deliveries.
1.4 WHAT ELSE IS DIFFERENT ABOUT MOBILE TV?
Mobile TV is designed to be received by cell phones, which are basically processors with their own operating systems (e.g., Windows Mobile) and application software packages (e.g., browsers, mailing programs). The handsets support the animation and graphics software packages such as Java or Macromedia Flash, players such as Real Player or Windows Media, etc. The operators have been aware of these capabilities and hence have designed content that takes advantage of the devices on which it will be played out. The new content that is prepared for mobile TV takes advantage of intermixing rich animations, graphics, and video sequences that play either natively or through software clients on mobile phones. The advantage is that the bandwidth used to deliver a flash animation file is a fraction of that used for delivering the same length of video. This means that mobile phones with all their limitations can indeed display very appealing content and presentation for simple programs such as weather or news. They can also be used to create entirely new services, such as chat or mail, that are delivered with video music and animations. The animation softwares such as Java or Flash basically taken from the PC world are, again, not ideally suited to the constrained environment of mobile sets. This has led to the need to adopt profiles of implementation that are suited to mobile devices. Java MIDP, Flash Lite profiles, and graphics delivered via scalable vector graphics SVG-Tiny or SVG-T are results of marathon standardization efforts across the industry to make a uniform environment for creation and delivery of content.
Watching mobile TV seems, quite deceptively, simple. After all it is but carrying the same pictures that are being broadcast anyway. But this simplicity hides a vast treasure of technologies and standards that have been developed over time to make the feat of bringing TV to the small 2-in. screens possible. Audio enthusiasts have long been used to handling over 30 types of audio file formats ranging from simple .wav files to .mpg, Real, QuickTime, Windows Media 9, and other file formats. Video has been available in no fewer than 25 different formats, from uncompressed video to MPEG-4/AVC. Moreover, video can be shown in a wide range of resolutions, frame sizes, and rates.
It has been a massive job for the industry to come together and agree on standards that will be used as a common platform for delivering mobile TV services. The standards may differ slightly based on technology, but the extent of agreement that has been achieved in a time frame as short as a decade reflects a new life cycle of technology and products. The effort required countless groups to work together. These ranged from chip designers and manufacturers to operating systems and application software designers, handset designers and manufacturers, software developers, the TV broadcast community, 3G mobile operators, and satellite TV broadcast operators, among the hundreds of stakeholders involved. It also involved the content generation industry, to design audio and video content for the mobiles; the broadcasting and the cellular mobile industries, to prepare the transmissions systems for handling of mobile TV; and many others.
The change, which became abundantly clear with the advent of mobile phones, had been in the air for quite some time. Mobile phones are no longer “phones,” but are multimedia devices for receiving and creating content, entertainment, and professional use. Their handsets can be connected to PCs, digital and video cameras, office systems, and a host of other devices to deliver or play multimedia files or presentations.
1.6 RESOURCES FOR DELIVERING MOBILE TV
A mobile phone is a versatile device. It is connected to cellular networks and at the same time receives FM broadcasts through its FM tuner or connects to a wireless LAN using Wi-Fi. The delivery of mobile TV can similarly be multimodal through the 3G networks themselves, 3G network broadcast extensions such as MBMS or MCBS, or satellite or terrestrial broadcast networks. In all these manifestations of delivery, a common resource that is needed is the frequency spectrum. The rapid growth of mobile TV and its momentum and scale were indeed an event that was not foreseen by the industry, though not all may agree with this statement. The result has been that the mobile TV industry has been left scrambling to search for ways to find its spectrum and deliver mobile TV. In the United Kingdom and the United States the traditional TV broadcast spectrum in UHF and VHF stands occupied by the transition to digital and the need to simulcast content in both modes. In the United Kingdom, BT Movio has fallen back on the use of the digital audio broadcast (DAB) spectrum to deliver mobile TV using a standard called DAB-IP. In Korea the DAB spectrum for satellite services was used to deliver services in a format named digital multimedia broadcast—satellite, or DMB-S. DVB-H is a standard largely designed to use the existing DVB-T networks to also carry DVB-H services and ideally use the same spectrum. This is indeed the case in many countries with the UHF spectrum being earmarked for such services. In the United States, where the ATSC systems do not permit “ride on” of mobile transmissions, the UHF spectrum remains occupied with digital transitions and spectrum is auctioned. Modeo, a DVB-H operator, has ventured to lay out an entirely new network based on DVB-H using the L-band at 1670 MHz. Another operator, HiWire, having spectrum in the 700-MHz band, is launching its DVB-H services using this spectrum slot. The United States (along with Korea and India) is also the stronghold of the code division multiple access technologies originated by Qualcomm. Qualcomm has announced a broadcast technology for mobile TV called mediaFLO, which will be available to all operators to provide mobile TV in a broadcast mode. Many other countries are set to use the same technology. In Korea the government also has allowed the use of the VHF spectrum for mobile TV services and this has led to the launching of the terrestrial version of the DMB services called DMB-T. In Japan, which uses ISDB-T broadcasting, the industry chose to allow the same to be used for mobile TV with a technology called 1-Seg broadcasting.
The scramble to provide mobile TV services by using the available networks and resources partly explains the multiple standards that now characterize this industry. Serious efforts are now on to find spectrum and resources for mobile TV on a regional or global basis that will in the future lead to convergence of the standards.
It is not only the users that comprise the mobile TV community. The new multimedia phones that can display mobile TV can also play music and that, too, taken directly off the networks rather than downloaded from a PC. The music content industry for sale to mobiles was born. The new opportunities unleashed by software for mobile TV and content development in Java or Flash made, in one go, millions of software developers working in this field of the industry. So it was with the chip set, with its associated software designers and developers who work in an industry in which nearly half a billion handsets can be sold in one year. The family expanded with new content creators, content aggregators, music stores, and e-commerce platform developers. The need to protect content so that the rights holders could receive their dues (unlike the early days of Internet content sharing) led to serious measures for digital rights management. The traditional community of content production in Hollywood indeed stands expanded manifold, encompassing all in the industry, be they cellular operators, broadcasters, content producers, or those in the vast software, hardware, and services industries.
1.8 NEW GROWTH AREAS FOR MOBILE TV
While mobile TV may appear to be an end in itself, it is in fact a part of the portfolio of multimedia services that can be delivered by the new generation of mobile networks. It is thus in company with multimedia messaging, video calling, audio and video downloads, multimedia client server or Java applications, presence location, instant messaging; the list is endless. Multimedia today empowers the user to take and transfer pictures and videos, prepare and deliver presentations, and run office applications. In fact the increasing use of multimedia was a foregone conclusion after the success of i-Mode services in Japan, which demonstrated the power of the data capabilities of the wireless networks. The launch of FOMA (Freedom of Mobile Multimedia Access) services with its 3G network took interactivity and multimedia applications to a new level. The new-generation networks empower the users to generate their own content, which can be broadcast or shared with others. The rich media services have become a part of all advanced third-generation networks.
The mobile TV provides a new opportunity to a wide range of users. The users get new power from the multimedia capabilities built into the handsets, which now include video and audio and multimedia applications properly configured to deliver live TV or video conferencing. The nature of content needed for mobile networks being different, the media industry also gets an opportunity to create new distribution platforms, target advertising, and reuse existing content for the new networks. The broadcast and cellular operators have been seeing a new growth market and there is considerable new opportunity for the manufacturing and the software industries.
1.9 IS MOBILE TV REALLY IMPORTANT?
A question that has been asked in millions of mobile TV blogs is whether mobile TV is really that important. Would anyone really watch TV on the sets once the initial craze was over? The answer, it would appear from initial responses, is probably in the positive. This is so because the mobile TV can be available widely through broadcast networks and watching the same is not necessarily going to be expansive. The users today are on the move, and refreshing new content and updates, fun, and music seem to be always welcome, as are the opportunities to remain connected using the new generation of smart phones. Continuous additions to the mobile phone capabilities, beginning with a simple camera, MP3 player, FM radio, and now mobile TV, have shifted the handset from a mere calling and answering device to being squarely a part of an advanced entertainment, Internet access, gaming, office application, mobile commerce, and utility device.
While the mobile TV is itself a very important tool, not only for live TV, but also for videoconferencing, video file sharing, group working, etc., an extensive use of mobile multimedia that forms the bedrock of delivery technologies is equally important. We are now squarely in this new age.