of 37 /37

seminar report

Embed Size (px)

Text of seminar report




ACKNOWLEDGEMENTThis project report could not have been prepared without the help and encouragement from various people. Hence for the same reason I would like to thank my faculties and my seniors without whom this report would have been a difficult task .It was for support that I got proper guidelines preparing my presentation . I would also like to thank my parents who helped me directly or indirectlyPRASHANT SINGH GAUTAM (0816131412) RAHUL MEHROTRA(0816131)








PREFACEThis project report is on the topic mobile television which sub divided into seven parts each and every par is bean deeply studied from the standard books and pages on the web for the simplicity of the reader each and every part is sub divided into headings with simple block diagrams and charts .we hope that our hard work will be appreciated by our teachers.Any suggestions for the improvement of this project report will be thankfully appreciated.


1. OBJECTIVEAlong with the progressive digital TV broadcasting technology,TV viewing is no longer restricted by time or space; the new trend is to watch digital TV programs through wireless mobile devices. So in this report we will discuss benefits of the contemporary mobile television over conventionalmovement restricted Television.

2.INTRODUCTIONMobile TV is the wireless transmission and reception of television content video and voice to platforms that are either moving or capable of moving. Mobile TV allows viewers to enjoy personalized, interactive television with content specifically adapted to the mobile medium. The features of mobility and personalized consumption distinguish mobile TV from traditional television services. The experience of viewing TV over mobile platforms differs in a variety of ways from traditional television viewing, most notably in the size of the viewing screen.

The technologies used to provide mobile TV services are digitally based,the terms unicast and multicast are used in the same way they are used for IPTV. That is, unicasting is transmission to a single subscriber, while multicasting sends content to multiple users. These definitions also correspond to those given for similar Internetbased applications.For network operators, the challenge has become: How can largescale delivery of high-quality multimedia to wireless devices be implemented profitably?Although delivery of this type of content is technically feasible over today's existing unicast networks such as 3G, these networks cannot support the volume and type of traffic required for a fully realized multimedia delivery service (many channels delivered on a mass market scale). Offloading multicast (one-to-many) multimedia traffic to a dedicated broadcast network is more efficient and less costly than deploying similar services over 3G networks.[1]4

Hence,various mobile TV standards can be designed to optimize the delivery of mobile TV.These systems are either totally terrestrially based,completely satellite based or a combination of both.Some of the standards include Digital Video BroadcastingHandheld(DVB-H),Digital Multimedia Broadcasting(DMB),Integrated Services Digital Broadcasting-Terrestrial(ISDB-T) and Media FLO. The standards employ advanced modulation techniques such as orthogonal frequency division multiplexing and are interoperable with mobile telecommunication networks.

3.MOTIVATIONThe development of multimedia coding technologies and mobile device implementation technologies makes it possible to serve a new multimedia broadcasting service over a mobile environment. Digital multimedia broadcasting (DMB), digital video broadcastinghandheld (DVB-H), and MediaFLO were recently proposed for mobile multimedia broadcasting serviceThe performance targets of these technologies are providing VCD(video CD) quality video and FM radio quality audio. There are currently two main ways of delivering mobile TV. The first is via a two-way cellular network, and the second is through a one-way, dedicated broadcast network. Each approach has its own advantages and disadvantages. Delivery over an existing cellular network has the advantage of using an established infrastructure, inherently reducing deployment costs. At the same time, the operator has ready-made market access to current cellular subscribers, who can be induced to add mobile TV to the services they buy.

The main disadvantage of using cellular networks (2G or 3G) is that mobile TV competes with voice and data services for bandwidth, which can decrease the overall quality of the mobile operators services. The high data rates that mobile TV demands can severely tax an already capacity-limited cellular system. Also, one cannot assume that existing

mobile handsets can receive mobile TV applications without major redesign and5

replacement. Issues such as screen size, received signal strength, battery power, and processing capability may well drive the mobile TV market to design hand-held receivers that provide a higher quality of voice and video than is available on most current cellular handsets.

Many 2G mobile service operators and most 3G mobile service providers are providing VOD or streaming video. These services are mainly unicast, with limited transmission capacity. They are built upon the underlying technologies used in the mobile cellular system itself GSM, WCDMA, or CDMA2000. An example of a technology designed to work on a 3G network is Multimedia Broadcast Multicast Service (MBMS), a multicast distribution system that can operate in a unicast or multicast mode. Mobile TV services over existing GSM and WCDMA cellular networks operates in the 5 MHz WCDMA bandwidth, and it supports six parallel, real-time broadcast streaming services of 128 kbit/s each, per 5 MHz radio channel.[1]


Comparison ofVideo Services over Mobile Networks [1]

Over 3G Network Network

Over Dedicated


3rd generation mobile networks

One way dedicated broadcast network .

Technology Platform MBMS MediaFLO DVB-H/SH DMB

Requires a new dual-mode handset capable of Receiver device Requires a standard 3G cellular phone receiving the broadcast signal and the cellular signal for phone calls and mobile Internet access.

Status of roll-out Relatively wide availabilityservice is available to any 3G subscriber on a network7

Limited availability in certain countries; trial stages elsewhere.

offering mobile TV Relative Limitations Cost of building a dedicated network. 3G network may not be able to support mobile TV traffic as the number of 3G voice and data users grow.


Live television VOD, instant messaging

Video Production

Professional videos

4.ISSUESThree issues have been studied regarding the mobile TV system: (1) TV signal transmission technology and how to enhance TV signal fault-tolerance or increase signal transport efficiency in order to improve display quality of TV programs; (2) Mobile TV application developments and provision of personal context aware services,recommending suitable TV programs according to user habits and preferences of watching TV; (3) How to enhance display quality, provide smooth TV programming if delays occur, and reduce power consumption in mobile TV players Concerning power-saving issues, two parts are discussed:


(1) Components of receiving TV signals, how to design receiver startup schedule while receiving a TV program signal to save receiver power; (2) Design a power-saving play mechanism according to TV program signal features, after received TV signal is converted to digital data by the demodulator. Hence, these issues can be resolved by using special dedicated networks for multimedia broadcasting on mobile TV.[3] Few of them are-: y y y Digital Video Broadcasting-Handheld (DVB-H), Digital Multimedia Broadcasting (DMB), and MediaFLO DVB-H has been identified as the mobile TV standard in most of Europe, due to its compatibility with GSM and WCDMA mobile standards. T-DMB is being used in the Republic of Korea, Indonesia and parts of Europe, and a satellite version of the technology (S-DMB) is operating in the Republic of Korea.[1]

5.DVB-H5.1 Introduction DVB-H is a broadcast/multicast technology that is a derivative of the existing DVH-T (digital terrestrial) standard, but designed for use with mobile devices.[2]Digital Video Broadcasting-Handheld (DVB-H) is based on Digital Video Broadcasting-Terrestrial (DVB-T) specification and provides a solution to lower receiver power consumption and improves mobile receiving performance. The common routes with DVB-T offer a major advantage as where there are existing DVB-T implementations adding DVB-H is cheaper than implementing a system from scratch.9

5.2 Features DVB-H is officially endorsed by the European Union as the "preferred technology for terrestrial mobile broadcasting or digital terrestrial television with additional features to meet the specific requirements of handheld, battery-powered receivers. In 2002 four main requirements of the DVB-H system were agreed: broadcast services for portable and mobile usage with 'acceptable quality'; a typical user environment, and so geographical coverage, as mobile radio; access to service while moving in a vehicle at high speed (as well as imperceptible handover when moving from one cell to another); and as much compatibility with existing digital terrestrial television (DVB-T), to allow sharing of network and transmission equipment.

5.3 Implementation This system is implemented in two major parts: a front-end buffer control mechanism and a parallel DVB-H TV signal decoding model.When receiving a DVB-H TV program signal from a base station, signal is demodulated to generate video and audio data. As video bit rate, quality, and resolution are directly related to content complexity, running too many buffers will consume power, while too few buffers will cause the program to fail to be played successfully.The parallel DVB-H TV signal decoding model uses a data partition processing method to run parallel DSP decoding of DVB-H videos on a heterogeneous multi-core platform. It also schedules videos according to the DVB-H video features, in order to reduce data dependency among the frames on a multicore platform.(refer to figure1).


Figure 2 shows the outline of the DVB-H/T system specifications for common TV broadcasting programs using the DVBT signal transfer mode. Senders can use an A/D converter to convert the analog video and audio signals to a digital signal, respectively, and use a Moving Picture Experts Group 2 (MPEG-2) codec technique to convert TV program data into MPEG-2 format. DVB-H service data are compressed and encapsulated into an IP packet then encapsulated into the transmission stream through a Multiprotocol Encapsulation (MPE) mechanism. Meanwhile, the time slicing data stream is added. Along with other DVB-T TV services, the multiplexer multiplexes it into a larger transmission stream (or multiple program transmission stream) before sending the data in a DVB wireless network. At the receiver, if a client wants to receive certain services, the receiver front-end circuit must run continuously in order to obtain the complete transmission stream. Then, the demultiplexer extracts the video, audio, and data information streams of the selected programs and delivers this information to the video decoder, audio decoder, and other applications for processing. The sender Multi-Protocol Encapsulation-Forward


Error Correction (MPE-FEC) and time slicing mechanisms are collectively called the DVB-H IP-Encapsulator, while the receiver reverse recovery portion is called the DVB-H IPDecapsulator. The IP data container format for each layer of DVB-H has an IP packet in the MPE section and redundant data in the FEC section. After Section format encapsulation, the MPE and FEC sections are connected end to end according to the encapsulating sequence to form a section data string. Then, it begins to slice the first and all of the other 184 bytes of each section data string. A 4-byte transmission stream header is added to the front of the 184-byte data length in order to complete a transmission stream encapsulation or MPEG2 transmission stream packet. Its data length is 188 bytes, with two major parts. The first is a data front-end header that occupies a 4-byte length with the available information, including a Sync. Byte = 47 hex for synchronizing the emitter and receiver, error indications, and stream packet recognition. The second part is the data transfer payload, which length is 184 bytes.

One ideal parallel process could double the system processing efficiency. As the video image format contained in the DVB-H TV signal is an H.264 baseline format,In H.264 decoding, pictures are divided into I frame, P frame, and B frame, where P frame is decoded according to the I frame picture data, and the B frame refers to the picture data12

of the I frame and the P frame.Unless there is good parallel processing, data collision will occur.When decoding two interdependent pictures, even when both pictures are simultaneously processed, the other picture must wait for a decoded reference before decoding.Therefore, how to utilize parallel processing to shorten the operation waiting time is the focus of many studies. However, DVB-H does promise significantly better quality and potentially lower pricing for consumers, while the interactive features, in-built program guide and recording abilities also promise a much better user experience.[3]

5.4 Market Exposure DVB-H has a stronger position in the European and Asian markets. Commercial services have already launched in Italy on three of the major mobile networks and other countries including Spain, France and Germany are set to follow. Future DVB-H devices may blur the line between mobile and fixed TV services.[2]


6.MEDIA FLO6.1 Introduction The MediaFLO system is an end-to-end mobile broadcasting technology that can deliver high-quality video to any mobile device.[5]The "FLO" part of the name is an acronym for Forward Link Only. Forward Link is another term for the downlink connection on a mobile phone, meaning that the system only sends data to the mobile devices and does not receive any data back from it.[9]Currently, the only commercially released devices that can receive the MediaFLO signal are mobile phones, but the technology is capable of sending the signal to any device equipped with a MediaFLO receiver.Qualcomm, an innovator in wireless technologies, has demonstrated the broadcast of a MediaFLO signal on several mobile devices that are NOT tied to any cellular network.[5] In the US, Qualcomm will broadcast its service on what used to be UHF Channel 55, which is roughly the 700MHz frequency band.[9]

FLO technology was designed specifically for the efficient and economical distribution of the same multimedia content to millions of wireless subscribers simultaneously. It actually reduces the cost of delivering such content and enhances the user experience, allowing consumers to surf channels of content on the same mobile handsets they use for traditional cellular voice and data services,also works in concert with existing cellular data networks, FLO effectively addresses the issues in delivering multimedia content to a mass consumer audience. Unencumbered by legacy terrestrial or satellite delivery formats, this technology offers better performance for mobility and spectral efficiency than other mobile broadcast technologies, offering twice the channel capacity.The FLO service is designed to provide the user with a viewing experience similar to a television viewing experience by providing a familiar type of program -guide user interface. ). One of the key features of this multicasting technology is that it requires about half as many base stations as in a regular cellular network.Unencumbered by legacy terrestrial or satellite delivery formats, FLO offers better performance for mobility and spectral efficiency with minimal power consumption.[7]14

Todays wireless operator will offer to consumers a service powered behind-the-scenes by a MediaFLO system based on FLO technology,a FLO-based programming lineup that utilizes 30 frames-per-second (fps) QVGA (a Quarter Video Graphics Array or 240x320 pixels) with stereo audio includes 14 real-time streaming video channels of wide-area content (ex: national content) and 5 real-time streaming video channels of local marketspecific content. This can be delivered concurrently with 50 nationwide non-real-time channels (consisting of pre-recorded content) and 15 local non-real-time channels, with each channel providing up to 20 minutes of content per day. non-real-time content can be delivered in the background seamlessly and made available for viewing in accordance with a provided program guide. The allocation between local and wide-area content is flexible and may vary during the course of the programming day. The delivery of nonreal-time content allows immediate access to music, weather or news summaries by topic while real-time streaming services support live events such as sports. In addition to widearea and local content, a large number of Internet Protocol (IP) data channels can be included in the programming line-up. Such channels may include (but are not limited to) traffic information, financial information or local weather updates.

The ability to change channels quickly is considered a key user requirement. Equally important is watch time, which is designed to be comparable to talk time, if not longer, so as not to compromise the functionality of the mobile device.In addition to viewing highquality video and audio content and IP data, the user may also have access to related interactive services, including the option to purchase a music album, ring tone, or download of a song featured in a music program. The user may also be able to purchase access to on-demand video programming, above and beyond the content featured on the program guide. The MediaFLO system, based on FLO technology, is able to deliver such a rich variety of content choice to consumers while efficiently utilizing spectrum as well as effectively managing capital and operating expenses for the service provider.[6]


6.2MediaFLO System Architecture

A MediaFLO system is comprised of four sub-systems: the Network Operation Center (which consists of a National Operations Center and one or more Local Operation Centers), FLO Transmitters, 3G Network, and FLO-enabled devices (also known as FLO Handsets).

6.2.1 Network Operation Center The Network Operation Center consists of the central facility(s) of the FLO network, including the National Operations Center (NOC) and one or more Local Operation Centers (LOC). The NOC can include the billing, distribution, and content-management infrastructure for the network. The NOC manages various elements of the network and serves as an access point for national and local content providers to distribute wide area content and program guide information to mobile devices.It also manages user-service subscriptions, the delivery of access and encryption keys, and provides billing information to cellular operators. The Network Operation Center may include one or more LOCs to serve as an access point from which local content providers can distribute local content to mobile devices in the associated market area.[6]

6.2.2 FLO Transmitters Each transmitter transmits FLO waveforms to deliver content to mobile devices.[6] 6.2.3 3G Network The 3G network belongs to the wireless operator(s) and supports interactive services to allow mobile devices to communicate with the NOC in order to facilitate service subscriptions and access key distribution.[6]


6.2.4 FLO-Enabled Devices FLO-enabled devices can receive FLO waveforms containing subscribed content services and program-guide information. FLO-enabled devices are primarily cell phones, which are actually multipurpose devices that serve as telephones, address books, Internet portals, gaming consoles, etc. Of all the various cell phone functions, the most important remains the ability to make and receive phone calls. Because all applications on a mobile device share common resourcesthe most important of which is battery powera service that wastes that power will quickly fail. FLO has been designed specifically to optimize power consumption through intelligent integration on the device and optimized delivery over the network.[6]

6.3 MediaFLO System Overview

6.3.1 Content Acquisition and Distribution

In a FLO network, content that is representative of a linear real-time channel is received directly from content providers, typically via a C-band satellite in MPEG-21 format (704 or 720 x 480 or 576 pixels), utilizing off-the-shelf infrastructure equipment. This is the most common format utilized by programmers, making it relatively simple for content providers to interface with a FLO System. The use of a standard definition as a source content provides sufficient resolution to allow for efficient transcoding to H.2642 QVGA resolution supported by the FLO network. Non-real-time content is received by a content server, typically via an IP link, and then reformatted into FLO packet streams and redistributed over a Single Frequency Network (SFN). This distribution of the FLO packet streams is facilitated by the MediaFLO Media Distribution System (MDS). This non-real-time content is delivered according to a prearranged schedule.


The transport mechanism for the distribution of this content to the FLO transmitter may be via satellite, fiber, etc. At one or more locations in the target market, the content is received and the FLO packets are converted to FLO waveforms and radiated out to the devices in the market via FLO Transmitters. If any local content is provided, it will be combined with the wide area content and radiated out to the target market.

Only those devices that have subscribed to the service may receive the content, which in turn can be stored on the mobile device for future viewing, in accordance with a service program guide, or as a linear feed of content, delivered in real-time to the device. This content may consist of high-quality video (QVGA) and audio (MPEG-4 HE-AAC3) as well as IP data streams. A 3G cellular network is required to provide control functions to support interactivity and facilitate user authorization to the service. Equally important, the 3G network provides a basis for interactivity, including purchase and download transactions.[6]

6.3.2 Power Consumption Optimization FLO technology simultaneously optimizes power consumption, frequency diversity4, and time diversity5. Other similar, but less efficient, systems optimize one or two of these parameters but ultimately compromise the others. FLO has a unique capability that allows it to access a small fraction of the total signal transmitted without compromising either frequency or time diversity. As a result of these considerations, it is expected that a FLO-enabled mobile device can achieve comparable battery life to a conventional cellular phone; that is, a few hours of viewing and talk time and a few days of stand-by time per battery charge.

The FLO air interface employs Time Division Multiplexing (TDM) to transmit each content stream at specific intervals within the FLO waveform. The mobile device accesses overhead information to determine at which time intervals a desired content stream is transmitted. The mobile device receiver circuitry only powers up during the time periods in which the desired content stream is transmitted; at all other times it is18

powered down. The receiver ON/OFF duty cycle is expected to be relatively low or immaterial, depending on the media content size and data rate used. FLO technology minimizes program channel acquisition time.[6] 6.3.3 Wide- and Local-Area Content FLO supports the coexistence of local and wide-area coverage within a single Radio Frequency (RF) channel. The content that is of common interest to all the subscribers in a wide-area network is synchronously transmitted by all of the transmitters. Content of regional or local interest can be carried in a specific market. This per market control is a key feature, offering the ability to blackout and retune based on any contractual obligations associated with specific programming.[6]

6.4 MediaFLO Technology Accessories Qualcomm, an innovator in wireless technologies, has demonstrated the broadcast of a MediaFLO signal on several mobile devices that are NOT tied to any cellular network. FLO technology is an open standard.Various devices compatible to MediaFLO are there y y y Personal media player MediaFLO Wi-Fi Accessory Mini-USB Accessory and many more.

6.4.1 Mini-USB Accessory A separate, yet dedicated device such as the MediaFLO Mini-USB Accessory with miniUSB interface has several advantages over a converged device. The ultra portable design allows users to plug it into any supported mobile device and watch streaming television and video anywhere the MediaFLO signal can be received.[5]


7. DMB-T7.1 Introduction DMB stands for Digital Multimedia Broadcasting and is a suite of systems used to send television and similar media programming over the air to mobile devices. DMB provided the first commercial digital mobile video broadcasting service of its kind in the world. S-DMB is a version that makes use of satellites, while T-DMB uses terrestrial (ground based) transmitters..[8]

T-DMB system was technically approved by the World DAB forum in November 2004 and finally published as an ETSI standard in June 2005. The DMB system defines the interactive data service functionality in order to provide additional information suitable for a display size and to prepare convergent services between broadcasting and Telecommunications.To meet the requirements of T-DMB, international standardsfor multimedia service and a more robust channel codingscheme were applied to the traditional DAB system.

One of the key features of this multicasting technology is that it requires about half as many base stations as in a regular cellular network(of media FLO technology).

7.2 TechnicalExplanation The standard is officially called Digital Terrestrial Multimedia Broadcast (abbreviated as DTMB). The standard was formerly named Digital Multimedia BroadcastTerrestrial/Handheld (abbreviated as DMB-T/H). The data transmission methodology implemented by the standard is TDS-OFDM (short for "Time Domain SynchronousOrthogonal frequency-division multiplexing"), which is primarily a multiple-carrier modulation technology, supporting both single-carrier and dual-carrier modulation schemes. DMB transmissions can be sent employing S-DMB(satellite Digital Media20

Broadcasting) for outdoor coverage and T-DMB(terrestrial Digital Media Broadcasting) for urban area and indoor coverage. DMB utilizes H.264 codec for video compression and BSAC or V2 for audio compression. The compressed audio and video is then transmitted in an MPEG2 stream as in DVB-H. To overcome the problems mobility introduced, T-DMB uses Forward Error Correction(FEC) like DVB-T. Time-slicing is used to achieve burst transmissions and this will enable power saving at the receiver. Despite the advantages, there are also shortcomings. Because the standard supports both single-carrier and dual-carrier modulation schemes, and because it does not define default video encoding standards, the R&D cost and complexity of IC chipsets for this standard will be higher, leading to more expensive receiver products.[11]

7.3 Market Exposure While it is running in trials in other countries, including some European ones, it is primarily used only in South Korea. The key difference between the South Korean and European standards is the way the video signal is transported.[8]


8.FUTURE OF MOBILE TELEVISIONThe future of mobile television lies in the combination of both unicast and multicast services available.[2]

9.SUMMARYStandards that form the basis for dedicated mobile television networks are following-:

9.1 DVB-H It is based on the DVB-T digital broadcast standard and is optimized for handheld terminals. DVB-H incorporates time-slicing to reduce power consumption and to allow time for a smooth handover from one cell to another. It is designed to operate in bandwidths of 5 MHz, 6 MHz, 7 MHz, and 8 MHz, which correspond to the bandwidths used by broadcasting services around the world.

9.2 Terrestrial Digital Multimedia Broadcasting (T-DMB) It is an enhancement of the T-DAB system to provide multimedia services including video, audio, and interactive data services for handheld receivers in a mobile environment. It operates in a channel bandwidth of 1.712 MHz and is completely backward-compatible with the T-DAB system for audio services.

9.3 Media Forward Link Only (MediaFLO) It is an end-to end system that enables broadcasting of video streams, audio-only streams, digital multimedia files, and data-casting to mobile devices, including handheld receivers. The system is designed to optimize coverage, capacity, and power

consumption for handheld receivers. It can operate in channel bandwidths of 5 MHz, 6 MHz, 7 MHz, or 8 MHz.[1]



We can conclude from the above study that deployment of mobile television over dedicated networks is suitable in most of the cases over 3G networks and moreover depending upon the requirement of the application various dedicated technologies are available which can be compared as follows-

Comparison of various technologies. Mobile Solutions TV 3G-MBMS T- DMB Digital Video Streaming on 3G Terrestrial Digital Multimedia Broadcasting MediaFLO Media Forward Link Only DVB-H Digital Video Broadcast to the Handset Transmitter 3G Network Repeater Terrestrial Transmitter Digital Terrestrial TV Transmitter

FLO Transmitter Data Rate 384 Kbps 1.4 Mbps 22-40 Km 11 Mbps Up to 25Km 11 Mbps Up 25Km Primary Use Worldwide Korea/Europe US Europe to

Coverage(1Tx) Up to 2Km



1. What is mobile TV?- www.ictregulationtoolkit.org/en/Section.3427.html


Nokia N77 Preview - DVB-H Mobile TV Handset-

www.allaboutsymbian.com/.../Nokia_N77_Preview-DVBH_Mobile_TV_Handset.php3. Power-Aware DVB-H Mobile TV System on Heterogeneous Multicore Platform-

www.hindawi.com/journals/wcn/2010/812356.html4. White Paper - DVB-H Broadcast to Mobile Devives-http://ispa-sat.ru/info/DVB-

H_White_Paper.pdf 5. MediaFLO Technology Accessorieswww.qualcomm.com/common/documents/.../MFT_Accessories_MWC09.pdf 6. FLOTM TECHNOLOGY OVERVIEWwww.mediaflo.com/news/pdf/tech_overview.pdf 7. Creating a Mobile Broadcast Platform - MediaFLOwww.mediaflo.com/news/.../mft_sys_prod_overview_brochure.pdfs