Amid the flurry of activity and hype surrounding mobile tv , various network models and technology platforms have emerged as contenders . Let's explore the options .
there is presently a great deal of Industry hype surrounding mobile television . said by some to be the next killer application of mobile sector and dismissed by others as having no sustainable business model , mobile tv is a conjure of possibilities . it lies at the eyes of maelstorm technologies network models and frequency bands , waiting for many trials to end and a manifestation of clue as to the most practical and commercially viable direction .
he notion of the television delivering signals to a moving receiver is not a entirely new concept . A no. of countries have for years enjoyed live digital tv in buses and trains . , courtasy of Digital video broadcasting - Terrestrial (DVB-T) Technology . Utilizing coded Orthogonal Frequency Division Multiplexing Modulation (COFDM) , DVB-T was originally designed with mobile applications in mind . The signal can accomodate variations in signal strength , field strength and multiple reflections that typically reach a receiver in motion .
However despite this foresight in it's development , DVB-T as it stands is not appropriate for broadcasting to handheld devices . Nor is its US counterpart The Advanced Television System committee (ATSC) standard , utilizing8 vestigial side band modulation , which was never designed for mobile applications .
Experiencing TV on handheld devices .raises a whole
new set of issues that has spawned several new broadcast technology platforms . Attracting the most attention Globally is the digital video broadcast to handheld (DVB-H) standard which is derived from DVB-T . The most important difference is that DVB-H transmits the signal bursts in order to conserve handset batery life . It also incorporates greater forward error correction essential for boosting handheld reception Another significant difference is that the data encapsulation technique . The DVB-H stream is an IP datacast at 200 to 500 kbps/program , yielding up to 50 programs in an 8 Mhz channel . This resolution is sufficient for the tiny handset . screen . In contrast , standard definition DVB-T uses MPEG-2 encoding at 4-5 Mbps /program yielding upto 5 standard resolution programs per channel .
DVB-H is not only mobile TV platform finding favor . Korea and China are first to embrace terrestrial digital multimedia broadcast (T-DMB) derived from eureka 147 digital audio broadcast (DAB) standard . Moreover USA Qualcom has developed the forward link only (FLO) technology for the delivery of multimedia content T-DMB , FLO , and DVB-H have delivery of multimedia copntent
To know more about these Technologies , Go through the following books
IP Multicast with Applications to IPTV and Mobile DVB-HImplementing Mobile TV, Second Edition: ATSC Mobile DTV, MediaFLO, DVB-H/SH, DMB,WiMAX, 3G Systems, and Rich Media Applications (Focal Press Media Technology Professional Series)
Digital Television, Third Edition: Satellite, Cable, Terrestrial, IPTV, Mobile TV in the DVB FrameworkMobile TV: Customizing Content and Experience (Human-Computer Interaction Series)
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