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Digital satellite multimedia broadcasting services in Europe are specified in the Mobile Satellite Services (MSS) frequency band by two recently developed standards, namely the European Telecommunications Standards Institute (ETSI) Satellite Digital Radio (SDR) and the Digital Video Broadcasting—Satellite services to Handhelds (DVB-SH) standards. Commercial deployment of operational systems based on these standards is foreseen in the coming years targeting mainly six large European markets. For these standards, a state-of-the-art channel code is deployed based on the 3rd Generation Partnership Project 2 (3GPP2) specifications having a wide range of coding rates. The purpose of this paper is twofold: (i) It studies and compares, for the first time, the Bit Error Rate (BER) performance of the 3GPP2 turbo code used in the aforementioned systems, in order to serve as a benchmark for system design engineers; and (ii) It investigates novel alternative channel coding schemes, including other state-of-the-art turbo code configurations and also Low-Density Parity-Check (LDPC) codes with linear-time encoding, such as the Irregular Repeat-Accumulate (IRA) codes, in order to improve the performance and/or reduce the complexity in future mobile satellite broadcasting systems. Extensive performance evaluation results in the Additive White Gaussian Noise (AWGN) and uncorrelated Rayleigh/Rician fading channels have shown that the use of turbo codes with higher number of states improves performance against the 3GPP2 turbo codes of up to 0.25 dB but the decoding complexity is almost doubled. Furthermore, the use of duo-binary turbo codes reduces decoding latency and makes them more robust in puncturing with performance improvement against the 3GPP2 turbo codes of up to 0.3 dB but performance degrades at very low coding rates. On the other hand, the use of Rate Compatible (RC)-IRA codes results in smaller performance improvement against the 3GPP2 turbo codes, i.e. up to 0.1 dB, but rate compatibility is used to obtain different coding rates with simple puncturing/extending method. [ABSTRACT FROM PUBLISHER]

Commercial terrestrial digital multimedia broadcasting (T-DMB) service was launched in the Republic of Korea. Reflecting recent demands of high quality video, Advanced T-DMB(AT-DMB) adopting a hierarchical modulation is being developed as the way to increase the payload data. Based on the AT-DMB system, this paper proposes a method to provide increased video quality with high spatial resolution. By using the emerging H.264/MPEG-4 AVC amendment 3 scalable extension (SVC), the proposed method is able to support high spatial resolution as well as the currently serviced spatial resolution while retaining the backward compatibility to T-DMB. In the experimental results, the benefits in terms of coding efficiency and spatial scalability are proven in comparison with the conventional T-DMB and alternative methods to provide a high spatial resolution video. [ABSTRACT FROM AUTHOR]

In this paper, we consider a peer-to-peer (P2P) network, where multimedia streams are broadcast by matched peers based on their resource reciprocation profiles. We propose a new framework where each peer creates a coalition of matched peers with which it can exchange resources in order to improve its utility. The utility is determined based on explicit consideration of the peer's multimedia attributes and the quality derived by the peers' reciprocation behavior. We adopt the proportional bargaining solution to negotiate the upload bandwidth among the matched peers. Proportional bargaining allows to determine each peer's optimal (in a Pareto optimal sense) upload rates in a coalition in terms of its utility impact. The impact of an incoming peer on the coalition value, which represents the collective utility achieved by the peers in a coalition, is assessed by explicitly investigating the coalition value improvement. Finally, our results show that the proposed coalition-based resource reciprocation can improve the resource allocation/scheduling algorithms deployed in existing P2P systems such as BitTorrent and CoolStreaming. We also discuss how the proposed resource reciprocation approach can be implemented in other multimedia broadcasting applications. [ABSTRACT FROM AUTHOR]

The interactive media platform(IMP) scheme proposed here provides an efficient solution for interactive digital TV in back-end. The platform actually integrates traditional TV guide system, interactive application execution system and digital video recorder(DVR) system together. The IMP consists of hardware infrastructures and middleware-based system software. This paper addresses a reference solution for interactive digital TV receiver that compliant with DVB-MHP. The architecture of IMP is proposed. The hardware architecture and middleware-based system software architecture are also presented respectively. In broadcast networks, all data including service information and interactive applications are transmitted from front-end to back-end periodically. Thus, broadcast latency is introduced to the platform while receivers processing broadcast data. Considering that broadcast latency has great influences to the platform performance, optimized strategies to reduce such latency while implementing is described in detail. The proposed platform has been implemented and the experimental result shows a good performance. [ABSTRACT FROM AUTHOR]

In this paper, we introduce a new scheme to improve the performance of the terrestrial - digital multimedia broadcasting (T-DMB) system, which exploits the burst error characteristics at the output of the convolutional decoder and the properties of the Reed-Solomon (RS) decoder to correct more errors by predicting erasures in each RS packet in advance as many as possible before decoding in the RS decoder. Simulation results show that the proposed scheme yields performance gain of around 1 dB at BER of 10-8 which can result in the extended coverage area of the T-DMB system. [ABSTRACT FROM AUTHOR]

The Hybrid Fiber Coax (HFC) is a modern broadband access network, providing advanced interactive services such as Internet access, digital interactive television and cable telephony. The edge costs dominate the cost of launching new services, at the time of deployment (CapEx) as well as for maintenance (OpEx). Therefore next-generation edge devices aim at the convergence of these services and their platforms into a single multi-service infrastructure, thus sharing resources and bandwidth. The focus of this paper is on the HFC access network design for bandwidth-intensive TV services, bringing standard as well as switched broadcast technologies into play. Standard broadcast TV service deployments, offered through the Digital Video Broadcast (DVB) platform, require low installation costs, but the bandwidth consumption increases linearly with the number of available TV channels, even for very unpopular channels. Switched broadcast TV channels, offered on the (Euro-) DOCSIS platform together with other interactive unicast services such as Video on Demand, are only streamed to a node on the HFC access network if they are requested locally, thus limiting bandwidth consumption for less popular channels. We present an access network design tool, based on an analytical TV traffic model, minimizing the installation cost on the edge devices and study the influence of the most important traffic and content parameters. [ABSTRACT FROM AUTHOR]

In this paper, we describe how the transmission technologies developed for over-the-air Digital Television broadcasting could be used to offer Interactive Television and Internet Multimedia Service. We propose to use the ATSC-DTV system for the downlink and DVB-RCT standard to implement a wireless return channel. This paper will also present some technical aspects of the system implementation. [ABSTRACT FROM AUTHOR]

In this paper, novel and yet simple techniques are presented to minimize the error propagation caused by the large precursors and postcursors of the decision feedback equalizer (DFE) in 8VSB DTV system. A technique that selects a reference tap (symbol timing of DFE) from an estimated channel impulse response (CIR) is presented to minimize the effect of the large precursors. Another technique that selects the reference tap position, i.e., decision delay in a feedforward filter (FFF), from the estimated CIR and the amplitude of the selected reference tap is proposed to minimize the effect of large postcursors. The combined structure of a feedback filter (FBF) and Viterbi decoder for use in 8VSB DTV system is also proposed to replace the past unreliable decision symbols in FBF as well as to reduce the decision error probability. Simulation results show that our proposed DFE can prevent effectively the error propagation, in particular, by changing the reference tap and its position in FFF according to the channel condition. It is also shown that an echo removing capability of the proposed DFE, where 400 and 620 taps are used for the FFF and FBF, respectively, is greater than that of conventional DFEs by about -20 μs in the single pre-echo of -10 dB channel and by about 10 μs in the single post-echo of -1 dB channel. [ABSTRACT FROM AUTHOR]

In this paper, we describe a new 1/4 rate robust modulation techniques for Enhanced-xVSB system which is fully backward compatible with ATSC 8-VSB standard. 1/4 rate mode Enhanced-xVSB system provides broadcasters with a wide choice of trade-offs of data rate vs amount of robustness of enhanced data for pedestrian/mobile services. Lab test results of proposed Enhanced-xVSB 1/4 rate mode robust stream is a significantly improved multipath as well as AWGN reception performance for Enhanced-xVSB receiver. We suggest an Enhanced-xVSB terrestrial broadcasting system for ATSC HDTV and pedestrian/portable TV simultaneous broadcasting service providing. [ABSTRACT FROM AUTHOR]

In a world driven by the accessibility of data for business, for communication and entertainment, but one populated by an increasingly nomadic society, it is no surprise that the appetite for wireless services continues to grow. The limitations of existing technologies however, particularly for wireless multi-casting and broadcasting, suggest that new approaches are needed to allow users to access services in the all wireless world. A popular approach for improving wireless services proposes to equip Mobile Terminals (MTs) with more than one radio interface to enable access to services in an always best connected paradigm. One such architecture envisages a co-operating overlay network, or inter-network, that comprises of a cellular telephony network and a digital broadcasting network. MTs in the inter-network have two corresponding radio interfaces and co-operation between the networks provide the user with seamless access to diverse services across the inter-worked platform. In this paper, we introduce novel location management proposals for co-operating overlay networks that incorporate a unidirectional broadcast overlay and provide a cost and latency analysis of the schemes. Our cost analysis demonstrates the soundness of the techniques and the value of the analyses as comparative evaluation tools. In particular, it is shown that there are a wide range of realistic operating conditions where the novel proposals presented here provide an optimum performance in cost terms. [ABSTRACT FROM AUTHOR]

In this paper we present the results of a study that examines the user's perception—understood as both information assimilation and subjective satisfaction—of multimedia quality, when impacted by varying network-level parameters (delay and jitter). In addition, we integrate eye-tracking assessment to provide a more complete understanding of user perception of multimedia quality. Results show that delay and jitter significantly affect user satisfaction; variation in video eye path when either no single/obvious point of focus exists or when the point of attention changes dramatically. Lastly, results showed that content variation significantly affected user satisfaction, as well as user information assimilation. [ABSTRACT FROM AUTHOR]

It has been demonstrated that turbo codes substantially outperform other codes, e.g., convolutional codes, both in the non-fading additive white Gaussian noise (AWGN) channel as well as multiple-transmit and multiple-receive antenna fading channels. Moreover, it has also been reported that turbo codes perform very well in fast fading channels, but perform somewhat poorly on slow and block fading channels of which the broadband fixed wireless access (FWA) channel is an example. In this paper, we thoroughly compare the performance of turbo-coded and convolutional-coded broadband FWA systems both with and without antenna diversity under the condition of identical complexity for a variety of decoding algorithms. In particular, we derive mathematical expressions to characterize the complexity of turbo decoding based on state-of-the-art Log-MAP and Max-Log-MAP algorithms as well as convolutional decoding based on the Viterbi algorithm in terms of the number of equivalent addition operations. Simulation results show that turbo codes do not offer any performance advantage over convolutional codes in FWA systems without antenna diversity or FWA systems with limited antenna diversity. Indeed, turbo codes only outperform convolutional codes in FWA systems having significant antenna diversity. [ABSTRACT FROM AUTHOR]

Video broadcasting has been proved to be an efficient technique to increase the scalability of a video-on-demand (VoD) system. In this paper, we address the problems in providing interactive functions for VBR encoded videos in a broadcast VoD system. A traffic smoothing scheme is proposed to support the VCR functions in delivering VBR videos over CBR channels by the staggered broadcasting protocol. By introducing a small buffering delay, the customers are able to join back to the broadcasting groups after the interactive functions. A system model is then developed to determine the optimal parameters such that the system can meet the delay requirement as well as provide the expected quality of service to the customers. The results show that the proposed system framework is very efficient in terms of bandwidth requirement and buffering delay to provide interactive VoD services. [ABSTRACT FROM AUTHOR]

This paper presents a new economic and effective TPEG (transport protocol experts group) application for location based service (LBS) that can be provided in terrestrial-digital multimedia broadcasting (T-DMB) transmission system. We propose a novel point-of-interest (POI) application interoperable with TPEG protocol, and introduce the POI data server/client and the DMB receiver with TPEG decoder implemented by using the proposed protocol. The stability and effectiveness of the proposed protocol is verified through the experimental broadcasting, and the pilot service using the commercial T-DMB network is being provided successfully. [ABSTRACT FROM AUTHOR]

Digital multimedia broadcasting service has been at the center of developing issues in mobile environment. in contrast to traditional multimedia broadcasting systems, mobile devices have limit of information handling capacity. In order to solve the problem, this paper presents a personalized channel recommendation system at client side in mobile environment. The system includes four modules: client manager agent, monitoring agent, data preparation agent and recommendation agent. Within the recommendation agent, we develop a recommendation algorithm using users' preference transitions for the channels. Also, we design and implement the prototype system on the Wireless Internet Platform for Interoperability. In the experiment, we compare the proposed algorithm with a conventional method. The experimental results show that the proposed recommendation system can provide better performance than the conventional method. [ABSTRACT FROM AUTHOR]

Hierarchical modulation can be effectively used to enhance terrestrial digital multimedia broadcasting (T-DMB) or digital audio broadcasting (DAB) systems in response to both the demand for higher data-rate and the need to be backward compatible with legacy receivers. QAM-type modulations are well-liked for hierarchical transmission but require coherent detection based on pilot symbol aided channel estimation. In the T-DMB or the DAB system using DQPSK modulation, however, any available pilot symbols except for the phase reference symbol do not exist. Differential amplitude phase shift keying (DAPSK) modulation is easily applied to the T-DMB system for a hierarchical modulation but may be susceptible to fast fading. As a good candidate for a hierarchical modulation of T-DMB to solve the above problems, we propose an amplitude differential phase shift keying (A-DPSK) modulation which is robust to fast fading by estimating only amplitude coefficients of the channel transfer function with the use of amplitude pilots. To raise the accuracy of channel estimation, we arrange the amplitude pilots in a come-type and introduce a noise-reduction scheme of averaging estimated channel coefficients. Simulation results show that the proposed A-DPSK provides a good choice for achieving a higher data-rate over other possible modulation schemes for advanced T-DMB or DAB systems. [ABSTRACT FROM AUTHOR]

This work proposes a quality-oriented multimedia delivery framework that tackles the issue of optimizing video broadcasting and interactive video applications over packet networks with respect to both resource utilization and user perceived quality. Previous work showed that the quality of service requirements of multimedia applications can be optimally satisfied by pipeline forwarding of packets by keeping delay controlled and resource utilization high, while enabling highly scalable network devices. These properties are key in today networks to enable valuable (i.e., chargeable for) services and to avoid that the traffic increase due to broadband video either collapses existing networks or forces the deployment of high cost, cutting-edge technology to properly upgrade them. However, the current Internet is not based on such technology and its incremental introduction raises questions on how to handle video packets generated by pipeline-forwarding-unaware sources. This work proposes to use the perceptual importance of the carried video samples to determine which packets shall be transferred with pipeline forwarding-thus receiving deterministic service-and which with a traditional, e.g., best effort or differentiated service. Two new scheduling algorithms are proposed, with an extensive analysis and simulation results, which also investigate the impact of the encoding scheme. Performance bounds have been established by comparing the proposed algorithms with an exhaustive-search approach, showing that the performance is within 2 dB PSNR from the optimal solution in the worst case. [ABSTRACT FROM AUTHOR]

We consider texture, luminance, corner and the edge information in the image to generate a mask that makes the addition of the watermark less perceptible to the human eye. The operation of embedding and extraction of the watermark is done in the frequency domain thereby providing robustness against common frequency-based attacks including image compression and filtering. We use decimal sequences for watermarking instead of pseudo random sequences, providing us with a greater flexibility in the choice of sequence. Weighted Peak Signal to Noise Ratio is used to evaluate the perceptual change between the original and the watermarked image. [ABSTRACT FROM AUTHOR]

While terrestrial mobile multimedia broadcasting presents an exciting opportunity for both innovation and convergence to provide multimedia services in new operating environments, it remains a challenge to locate frequency spectrum in which to deploy these applications. The fact is that the frequencies suitable for such applications in a mobile environment are already heavily encumbered, and it is difficult to locate bands that are harmonized, even on a regional basis. Nonetheless, there are also opportunities for new mobile multimedia broadcasting applications, given the transition to technologies that more efficiently utilize spectrum, such as in the case of the analog to digital television transition. [ABSTRACT FROM AUTHOR]

A converged broadcast and telecommunication service platform is presented that is able to create, deliver, and manage interactive, multimedia content and services for consumption on three different terminal types. The motivations of service providers for designing converged interactive multimedia services, which are crafted for their individual requirements, are investigated. The overall design of the system is presented with particular emphasis placed on the operational features of each of the sub-systems, the flows of media and metadata through the sub-systems and the formats and protocols required for inter-communication between them. The key features of tools required for creating converged interactive multimedia content for a range of different end-user terminal types are examined. Finally possible enhancements to this system are discussed. This study is of particular interest to those organizations currently conducting trials and commercial launches of DVB-H services because it provides them with an insight of the various additional functions required in the service provisioning platforms to provide fully interactive services to a range of different mobile terminal types. [ABSTRACT FROM AUTHOR]