As if city sidewalks weren't bumptious enough, the day may soon come when pedestrians not only chat on their cell phones as they stroll, but also check the highlights of the big game, catch satellite images of the latest Gulf Coast storm or send a clip from a Norah Jones video to a friend's cell phone. Technical advances shown last week at the International Broadcasting Convention (IBC) in Amsterdam, Netherlands, have turned mobile TV on cell phones from a harebrained scheme to a sure thing sometime within the next 18 months.
IBC saw demonstrations of mobile TVs, handsets embedded with digital TV receivers, DTV-compliant silicon tuners and low-power coded orthogonal frequency-division multiplexing (COFDM) demodulation and baseband-processing ICs. Infrastructure components such as encoders, multiplexers, monitoring systems and video gateways for digital mobile broadcasts were also showcased.
Besides the acceleration of technology, a key breakthrough that may finally get broadcasters out of the house was conceptual: the consensus among developers that mobile TV requires a different form factor and content composed of clips, teasers, samples and interactive Internet links, rather than a movie, a sitcom or even a 10-minute music video.
While it appears certain that mobile TV will come to consumers in bite-size portions, no one yet knows how it will get there. Handset users may be tuning in via terrestrial digital TV airwaves, digital radio spectrum, or 2.5- or third-generation (3G) cellular networks. Indeed, this embarrassment of choices may be the biggest headache broadcasters face.
Among the candidates as de facto mobile-broadcasting standard are Digital Multimedia Broadcast (DMB) over Eureka-147-based Digital Audio Broadcasting spectrum; Digital Video Broadcast-Handheld (DVB-H), which is based on the terrestrial digital TV standard; and Multimedia Multicast/Broadcast services over 3G cellular networks.
Further, DMB comes in two flavors: T-DMB, using terrestrial airwaves, and S-DMB, based on satellite. Japan has its own proprietary terrestrial digital TV standard, for which it set aside 1/13th of the digital TV transmission frequency band for mobile broadcasting for automotive and handset applications.
DMB and DVB-H were the star-quality standards on the IBC show floor. Asked which of them is likely to survive, many observers on IBC panels hedged. "I just don't know," said Ulrich Reimers, a professor at the Technical University of Braunschweig, Germany. "Clearly, both DMB and DVB-H still need to prove themselves."
To handicap the likeliest success stories this early, one needs to weigh technical, commercial and regulatory issues, said Mike Brooks, chairman of mobile applications within the U.K.-based Digital TV Group. "If any one of these elements is missing, the whole thing will fall over," Brooks said.
Those involved in ongoing mobile-broadcasting trials said at IBC that consumers have "a great appetite" for watching TV, particularly live content, on cell phones. But the paradigm must be "snacking," not a full meal of broadcast fare, they said. Such video tidbits can provide a portal to mobile Internet services, said advocates, thus opening a fresh opportunity for network operators to make money.
Moreover, mobile-broadcast technologies are practically ready for commercial deployment. Chip companies such as Texas Instruments, Frontier Silicon, Panasonic and Bosch are offering COFDM demodulation/baseband processors for mobile-on-TV receivers based on DMB. Both Samsung and LG Electronics are developing their own DMB media processors internally. Hitachi, Atmel and Samsung Electro-Mechanics are among those supplying DMB tuners.
On the DVB front, Nokia has a mobile handset that can be attached to a sleek DVB-T receiver and extra battery. And Xceive Corp., a startup developing RF-to-baseband receiver ICs, previewed a complete silicon tuner for DVB-H at IBC. The tuner, called XC3510, will start sampling next month so that "carriers and handset vendors can use it now in trials to understand if there are any DVB-H issues related to the number of transmitters or necessary power density," said Ramon Cazares, director of marketing at the Santa Clara, Calif., company.
There is even spectrum already dedicated to mobile broadcasting. Crown Castle USA (Houston) won a recent FCC auction, quietly buying an exclusive terrestrial license for 5 MHz of the nationwide L-band spectrum, previously used for U.S. weather balloon and weather satellite downlinking but recently freed up. The company launched a three-site Single Frequency Network trial in Pittsburgh this year built on DVB-H technology.
South Korean broadcasters and consumer device manufacturers wowed the European audience at IBC with the speed of their T-DMB-based mobile-DTV project. With mobile broadcast scheduled for rollout in Korea later this year, the Koreans claimed to have leapfrogged Europe, where DVB-H trials have just begun.
While the rest of the world was trying to leverage a terrestrial digital TV standard for mobile broadcasting, Koreans were "busily working away" at adding a few modifications to an almost decade-old Eureka-147-based DAB technology for video applications, said Anthony Sethill, chief executive officer of Frontier Silicon, a leading DAB chip supplier armed with its own low-power-consumption DMB silicon. "DMB works fabulously," Sethill said.
T-DMB uses ITU-T H.264 coding for video and MPEG-4 bit-sliced arithmetic coding for audio. It then multiplexes them, together with extra data, by using an MPEG-4 synchronization layer and MPEG-2 transport stream.
Because of similarities among basic building blocks in DMB and DVB-H, it is unlikely that two handsets, each featuring a different mobile-TV standard, will end up being vastly different in quality or power consumption.
However, Jeonghoon Park, senior engineer in the Mobile Solution Lab at Samsung Electronics, said DAB enjoys several advantages. They include an already well-established DAB network infrastructure, a more cost-effective coverage area that requires less investment and a number of chip companies that have already developed DMB silicon, he said.
Others believe the Achilles' heel of DVB-H may be frequency. Frontier Silicon's Sethill cautioned that TV frequency allocation, tightly regulated by governments, might hobble the deployment of DVB-H. In contrast, DMB can plug into a widely installed DAB infrastructure that already reaches 80 percent of Europe, he said.
Rather than leveraging the DAB infrastructure, DVB-H proponents believe the best way to go in terms of securing enough bandwidth and building a collaborative network with mobile operators is creating a converged platform built on a 2.5G/3G cellular network and a digital terrestrial TV broadcast infrastructure. Using DVB-H, combined with Internet Protocol (IP) datacasting, Europe which led the world in the mobile-communication revolution with the GSM standard believes it has the eventual winning formula.
Via terrestrial digital TV, DVB-H delivers multimedia content encapsulated in IP packets to large audiences at lower cost, without clogging a cellular network, DVB-H promoters say. The spec also creates opportunities for mobile operators, through their billing mechanisms, to carry and charge for the new broadcast services, they said.
DVB-H adds new features, modifications and options to DVB-T's technical specifications, seeking lower power, more robust mobility and better quality-of-service in portable TV reception. These include time slicing, multiprotocol encapsulation-forward error correction and options such as air interface enhancement and additional signaling.
Because of the flexible network infrastructure designs allowed in DVB-H, it's possible to multiplex DVB-H services in an existing terrestrial DTV network based on DVB-T. Also, DVB-H services can be launched on a newly dedicated DVB-H network, independent of terrestrial digital TV.
Crown Castle USA opted for the second option. The move opened the door to DVB-H deployment in the United States, where a rival terrestrial DTV system called the Advanced Television Systems Committee standard is deployed. Currently, the U.S. digital terrestrial system (based on ATSC) does not have its own mobile-TV broadcasting spec. Doubts persist that its 8VSB-based modulation scheme will work for mobile transmission.
Crown Castle chose DVB-H because of the robustness of its mobile-TV broadcast standard, Michael Schueppert, senior vice president of business development at Crown Castle, said at an IBC panel. While the current trial in Pittsburgh is small-scale, Schueppert said, "The DVB-H is working very nicely and its performance is exceeding expectations."
Cramming more than one receiver for different TV broadcast standards into a mobile handset already constrained by battery power is out of the question. Also, there are other questions about such matters as antenna installation, said Simon Mason, head of new-production development at broadband Internet provider NTL. DMB's antenna, for example, is still "too large to make a [TV-capable] mobile phone sexy," he said. "It needs to be knocked out."
Regardless of the broadcast transmission standard chosen, handset vendors will need a very tiny digital TV receiver tuner. They will be asking for a silicon tuner with no shield requirement and no external filters.
What about content?
Technology issues aside, IBC participants agreed that mobile-TV broadcasting will require content reformatting. The use of zoom or slow motion is essential so that viewers can digest the content better on a small display, they said. Asked if consumers may be put off by poor video quality, lower frame rates and jerky motion on a tiny screen, Masai Suenaga, vice president of Mobile Broadcasting Corp., a Tokyo-based provider of satellite mobile digital TV broadcasts, said consumers have proven to be quite forgiving even in Japan. "They buy video on their mobile handsets not for video quality but for information," Suenaga said. "They understand the limitations."
Toru Sano of Nippon Television Network Corp. defined mobile TV as "a portal for mobile Internet services." For example, a short video clip from a soccer broadcast can whet the consumer's appetite, triggering links related to the game or an individual player, or offering the option to watch more of the game.
NTL's Mason said that a Cambridge, England, trial conducted in tandem with Microsoft and Tandberg is carefully studying consumers' viewing habits. "We need to understand how much of the content is cached into a handset as 'take-it-with-you' content, while how much is consumed as it's broadcast."
One unanswered question is whether broadcasters and mobile operators will end up as friends or foes in this market. Because mobile-TV broadcasting is still wedded to mobile telephony, broadcasters will need to work with mobile operators, rather than against them. Acknowledging that a precise business model still needs to be sorted out, Crown Castle's Schueppert said, "Different people need to come together."
As Suenaga noted, "Broadcasters know their weaknesses." The ability to bill for content, for example, is not their specialty. But "mobile operators also know their weaknesses," Suenaga said. Broadcasters can offer far more economical one-to-many content delivery, for example, and tailoring TV programming for mobile handsets is more the business of broadcasters than of network operators.
"Once mobile-TV reception becomes a standard feature of a mobile handset, it will penetrate the market very quickly," Schueppert predicted. "The cellular-phone business is very much a fashion-oriented business."