Many analysts see a strong market for mobile TV, provided that it is packaged and priced correctly, but others offer a much more conservative viewpoint. Mobile TV broadcasts have started in South Korea, Japan, and the United States, with a number of other trials taking place around the world. For example, in the United States, Verizon Wireless (www.verizonwireless.com) has launched V-Cast, offering dozens of channels with 60-second "mobisodes" for US$15 per month, and Cingular (www.cingular.com) and Sprint Nextel (www.sprint.com) both offer MobiTV for US$10 per month. Many other countries are also beginning to offer mobile TV as well.
A number of vendors are preparing for mobile digital TV solutions. It is already becoming a standards war. As discussed in the next sections, the following standards are being promoted in different places around the world:
Which of these standards lives to dominate remains to be seen. After all, we have never created a global standard for analog TV, but then again, normal TVs aren't mobile and therefore don't require a global standard. Other issues need to be addressed, including potential regulatory problems, spectrum planning, network and access capacity, the reality of figuring out how to actually make money (monthly subscription fees? pay-per-view? pay-per-minute?), the fact that such offerings stand to cannibalize other 3G data services, the usability factor (will people actually want to watch TV on a 2-inch screen?), and, most importantly, content issues.
TV plays a significant role in the lives of people worldwide. In addition, mobile subscriber penetration has reached, if not surpassed, what is statistically a very high level of saturation in many markets. Finally, there is little doubt about the inevitable convergence of the broadcast and mobile industries because it is already happening. Therefore, broadcast mobile TV definitely has potential, and interactive TV and the extension of advertising are at the forefront of that success.
DMB was the first mobile TV standard to market, being put into use in a number of countries. It is currently operating in South Korea, where S-DMB (satellite DMB) and T-DMB (terrestrial DMB) services are in use. There are also some T-DMB trials currently occurring and planned around Europe. Germany is launching T-DMB for the 2006 World Cup. France is currently conducting a trial in Paris. Switzerland, Italy, and the United Kingdom are also preparing for trials during 2006.
The DMB standard is derived from the Digital Audio Broadcasting (DAB) standard that enjoys wide use in Europe for radio broadcasts. The acronym DAB is used both to identify the generic technology of digital audio broadcasting and specific technical standards, particularly the Eureka 147 (EU147) standard. DAB is based on Orthogonal Frequency Division Modulation (OFDM) for transmitting digital data over a lossy radio channel. DAB broadcasts use the MP2 audio coding technique, a close relative of the popular MP3 format, which was also created as part of the EU147 project.
S-DMB is a new concept in multimedia mobile broadcasting service that converges telecommunications and broadcasting. S-DMB delivers high-quality content for both stationary and mobile clients. It uses the same Code Division Multiplexing (CDM) technology as the mobile phone service. Initially, there are 3 video channels among the 9 offered; the other 6 are audio channels. Eventually there will be a total of 39 channels: 11 for video, 25 for audio, and 3 for data. As a satellite-based service, one of S-DMB's problems may be reception within buildings. SK Telecom (www.sktelecom.com), for instance, plans to overcome this problem by extending the signal receiving areas by installing "gap fillers," although not all areas will get filled. Another drawback is the lack of available handsets.
Whereas S-DMB was developed mostly by the private sector, T-DMB was part of South Korea's national initiative to digitize radio broadcasting. T-DMB has reason to be encouraged. In March 2005 the Korean Broadcasting Commission (www.kbc.go.kr/english), which regulates South Korea's airwaves, selected three broadcasting companies and three consortia comprising dozens of companies each to provide terrestrial-based multimedia services. A big plus for T-DMB is that terrestrial broadcasts will be free because the government forbids charging for what are considered public broadcasts. Although DMB is proprietary and designed for the Korean market, because DMB can send content to numerous consumers on the same frequency band, the technology scales gracefully and profitably. In fact, as the number of users increases, operational costs decrease. As a result, Korea is interested in having DMB adopted globally as a standard. Both LG (www.lg.co.kr/english) and Samsung (www.samsung.com) have major investments in DMB and hope that it will be adopted throughput Europe as a standard. South Korea's ministry of communications has created a special task force to lobby for European use of the DMB standard, and Korean companies have performed several demonstrations.
The ETSI chose DVB-H as a standard in November 2004. ETSI recommendations for a standard are voluntary, not compulsory, but DVB-H has already generated significant industry activity, including technical and commercial trials and a range of product launches. Based on DVB-T, DVB-H is fully backward compatible. It offers additional features to support handheld portable and mobile reception. The specification calls for 15Mbps in an 8MHz channel. Key advantages of DVB-H include the fact that it saves batteries and offers mobility with high data rates, single-antenna reception, impulse noise tolerance, increased general robustness, and seamless handoffs.
DVB-H is meant for IP-based services. It can share DVB-T "multiplex" (i.e., the bandwidth of a DTV channel subdivided into multiple subchannels) with MPEG-2 services. For a TV-like experience on a handheld device with a smaller screen, the next-generation MPEG standard (MPEG-4-AVC) will be needed. Although DVB-H will deliver a TV broadcast signal to a mobile TV device, any two-way interaction would be handled by mobile networks such as GPRS, EDGE, or 3G.
Technical trials of DVB-H services are currently under way in Europe, the United States, and Australia, and major events such as the International Broadcasting Convention (IBC; www.ibc.org), the 3GSM World Congress (www.3gsmworldcongress.com), CeBIT (www.cebit.de), and DVB World (www.iab.ch/dvbworld2006_prog.htm) have featured full end-to-end demonstrations. Commercial launches of DVB-H services are occurring in 2006 in Italy and the United States. Most major U.S. markets are expected to have DVB-H infrastructure ready for use by 2007.
ISDB encompasses several core standards, including ISDB-S (satellite TV), ISDB-T (terrestrial digital TV), ISDB-C (digital cable TV), and ISDB-Tsb (terrestrial digital sound broadcasting in the 2.6GHz band). The TV standards are all based on MPEG-2 video and audio coding and can deliver high-definition TV (HDTV). ISDB-T and ISDB-Tsb are for mobile reception in TV bands.
The ISDB standards vary in the modulation schemes used due to the particular requirements of the different frequency bands. ISDB-S uses PSK modulation; ISDB-T and ISDB-Tbs use QPSK, DQPSK, 16-QAM, or 64-QAM; and ISDB-C uses 64-QAM.
Japan adopted ISDB-T in commercial transmissions in December 2003, and it had a total market of about 100 million TV receivers in early 2006. (ISDB standards are discussed in more detail in Chapter 10.)
MediaFLO, a wireless innovation from Qualcomm (www.qualcomm.com), is a comprehensive end-to-end solution that simultaneously and cost-effectively delivers very high volumes of high-quality, streaming, or clipped audio and video multimedia to wireless subscribers. Based on Qualcomm's proprietary Forward Link Only (FLO) technology, it is an air interface with multicast delivery capabilities designed to increase capacity and reduce content delivery costs to mobile handsets. It is designed from the ground up for superior mobility. FLO is based on OFDM outbound high-speed technology.
MediaFLO works on the 700MHz spectrum and is being embraced in the United States. However, global movements are also involved, largely through the FLO Forum (www.floforum.org). The purpose of the FLO Forum is to assemble wireless industry stakeholders around the central mission of establishing FLO as an internationally supported technology standard. Its position is that FLO technology is poised to significantly change the way multimedia is delivered to mobile devices. As these changes take hold, possibilities for the entire wireless industry stand to increase dramatically.
MediaFLO is designed to be a one-way, high-speed wireless system to deliver content, including audio and video, to mobile devices. The concept is to make the channels (multiple) CDMA and W-CDMA operators. Mobile virtual network operators (MVNOs) and resellers of the service and/or content are expected to make use of the network. (MVNOs are companies that do not own licensed spectrum of their own but instead make use of another mobile operator's network, while reselling the wireless services under their own brand names.) But wireless operators are not the only potential customers of MediaFLO; the technology is seen as an ideal way for broadcast stations to include an entire new group of viewersmobile users. MediaFLO will be made available to both CDMA and W-CDMA network operators and TV, cable, and satellite operators. The major innovation is that MediaFLO will allow content that is usually available only for fixed viewing to now be available to mobile devices, whether they are laptops or mobile phones equipped with color screens and enough storage to buffer the content. This obviously suggests that mobile devices will need to accommodate mass storage and the ability to cache content for later viewing, allowing customers who experience any problems in live reception to view the program later. And, of course, the system must ensure full security.
Whereas TV stations can broadcast a single program in the 6MHz or 8 MHz of bandwidth allocated to broadcast TV, MediaFLO can deliver between 50 and 100 nationwide and local content channels, including up to 15 live streaming channels and numerous clip-case and audio channels. Wireless service providers can send audio, video, and large data files to the customer while also maintaining their own data channels for other two-way applications. Using Quarter Video Graphics Array (QVGA) resolution, 30fps video, and high-quality stereo audio, the content on MediaFLO channels promises to be delivered in a familiar and easy-to-use format.
With MediaFLO, each wireless device requires a receiver and circuitry capable of receiving the 700MHz band in addition to traditional transceivers on the 850MHz and 1,900MHz bands (in the United States). Of course, we anticipate that such devices will be available shortly. Being based on the 700MHz band, MediaFLO has better coverage than the 850MHz or 1,900MHz bands. The fact that it is an outbound-only system means that it requires fewer 700MHz transmitters to cover the United States than do standard wireless two-way systems. According to Qualcomm's estimates, MediaFLO will be able to provide nationwide coverage with 30 to 50 times fewer transmitter sites, which represents a huge savings in building the system.
Designed as an end-to-end solution, MediaFLO has given consideration to everything needed to make the system work, including the MediaFLO content distribution system, program guides that will be available to customers, a billing system, and the 700MHz channels over which the content will be delivered. MediaFLO is scheduled to go live in the United States in 2006. Qualcomm says that it will require about $800 million to build the system, some of which may come from third parties. It is likely that the system will be built on a city-by-city basis. MediaFLO could be deployed today in some areas of the country where UHF-TV channels 54, 55, and 56 are not in use. As the UHF-TV stations on these channels are turned off or moved in other cities, MediaFLO can be brought online.
Part I: Communications Fundamentals
Telecommunications Technology Fundamentals
Traditional Transmission Media
Establishing Communications Channels
Part II: Data Networking and the Internet
Data Communications Basics
Local Area Networking
Wide Area Networking
The Internet and IP Infrastructures
Part III: The New Generation of Networks
Broadband Access Alternatives
Part IV: Wireless Communications
Wireless Communications Basics
WMANs, WLANs, and WPANs
Emerging Wireless Applications