The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Thomas Stockhammer - One of the best experts on this subject based on the ideXlab platform.
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advancedwireless multiuser video streaming using the scalable video coding extensions of h 264 mpeg4 avc
International Conference on Multimedia and Expo, 2006Co-Authors: Guenther Liebl, Thomas Schierl, Thomas Wiegand, Thomas StockhammerAbstract:We propose a dynamic sharing of radio resources in a wireless multiuser system by combining a flexible video coding scheme, namely the currently developed scalable video coding (SVC) extension of H.264/AVC with appropriate radio link Buffer Management for multiuser streaming services. The paper introduces the components of the proposed system and the used cross-layer interface. Simulation results verify the benefits of our approach.
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Radio Link Buffer Management and Scheduling for Wireless Video Streaming
Telecommunication Systems, 2005Co-Authors: Günther Liebl, Hrvoje Jenkac, Thomas Stockhammer, Christian BuchnerAbstract:In this paper we compare strategies for joint radio link Buffer Management and scheduling for wireless video streaming. Based on previous work in this area [8], we search for an optimal combination of scheduler and drop strategy for different end-to-end streaming options including timestamp-based streaming and ahead-of-time streaming, both with variable initial playout delay. We will show that a performance gain versus the two best drop strategies in Liebl et al. [8], i.e. drop the HOL packet or drop the packet with the lowest priority starting from HOL, is possible: Provided that some basic side-information on the structure of the incoming video stream is available, a more sophisticated drop strategy removes packets from an HOL group of packets in such a way that the temporal dependencies usually present in video streams are not violated. This advanced Buffer Management scheme yields significant improvements for almost all investigated scheduling algorithms and streaming options. In addition, we will demonstrate the importance of fairness among users when selecting a suitable scheduler, especially if ahead-of-time streaming is to be applied: Given a reasonable initial playout delay at the streaming media client, both the overall achievable quality averaged over all users, as well as the individual quality of users with bad channel conditions can be increased significantly by trading off fairness with maximum throughput of the system.
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joint Buffer Management and scheduling for wireless video streaming
International Conference on Networking, 2005Co-Authors: Günther Liebl, Hrvoje Jenkac, Thomas Stockhammer, Christian BuchnerAbstract:In this paper we revisit strategies for joint radio link Buffer Management and scheduling for wireless video streaming. Based on previous work [1], we search for an optimal combination of scheduler and drop strategy for different end–to–end streaming options. We will show that a performance gain vs. the two best drop strategies in [1], ie drop the HOL packet or drop the lowest priority packet starting from HOL, is possible: Provided that basic side-information on the video stream structure is available, a more sophisticated strategy removes packets from an HOL group of packets such that the temporal dependencies usually present in video streams are not violated. This advanced Buffer Management scheme yields significant improvements for almost all investigated scheduling algorithms and streaming options. In addition, we will demonstrate the importance of fairness among users when selecting a suitable scheduler.
Petar Popovski - One of the best experts on this subject based on the ideXlab platform.
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harq Buffer Management an information theoretic view
International Symposium on Information Theory, 2015Co-Authors: Wonju Lee, Osvaldo Simeone, Joonhyuk Kang, Sundeep Rangan, Petar PopovskiAbstract:A key practical constraint on the design of Hybrid automatic repeat request (HARQ) schemes is the modem chip area that needs to be allocated to store previously received packets. The fact that, in modern wireless standards, this area can amount to a large fraction of the overall chip has recently highlighted the importance of HARQ Buffer Management, that is, of the use of advanced compression policies for storage of received data. This work tackles the analysis of the throughput of standard HARQ schemes, namely Type-I, Chase Combining and Incremental Redundancy, under the assumption of a finite-capacity HARQ Buffer by taking an information-theoretic standpoint based on random coding. Both coded modulation, via Gaussian signaling, and Bit Interleaved Coded Modulation (BICM) are considered. The analysis sheds light on questions of practical relevance for HARQ Buffer Management such as on the type of information to be extracted from the received packets and on how to store it.
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harq Buffer Management an information theoretic view
arXiv: Information Theory, 2015Co-Authors: Wonju Lee, Osvaldo Simeone, Joonhyuk Kang, Sundeep Rangan, Petar PopovskiAbstract:A key practical constraint on the design of Hybrid automatic repeat request (HARQ) schemes is the size of the on-chip Buffer that is available at the receiver to store previously received packets. In fact, in modern wireless standards such as LTE and LTE-A, the HARQ Buffer size is one of the main drivers of the modem area and power consumption. This has recently highlighted the importance of HARQ Buffer Management, that is, of the use of Buffer-aware transmission schemes and of advanced compression policies for the storage of received data. This work investigates HARQ Buffer Management by leveraging information-theoretic achievability arguments based on random coding. Specifically, standard HARQ schemes, namely Type-I, Chase Combining and Incremental Redundancy, are first studied under the assumption of a finite-capacity HARQ Buffer by considering both coded modulation, via Gaussian signaling, and Bit Interleaved Coded Modulation (BICM). The analysis sheds light on the impact of different compression strategies, namely the conventional compression log-likelihood ratios and the direct digitization of baseband signals, on the throughput. Then, coding strategies based on layered modulation and optimized coding blocklength are investigated, highlighting the benefits of HARQ Buffer-aware transmission schemes. The optimization of baseband compression for multiple-antenna links is also studied, demonstrating the optimality of a transform coding approach.
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HARQ Buffer Management: An Information-Theoretic View
IEEE Transactions on Communications, 2015Co-Authors: Wonju Lee, Osvaldo Simeone, Joonhyuk Kang, Sundeep Rangan, Petar PopovskiAbstract:A key practical constraint on the design of hybrid automatic repeat request (HARQ) schemes is the size of the on-chip Buffer that is available at the receiver to store previously received packets. In fact, in modern wireless standards such as LTE and LTE-A, the HARQ Buffer size is one of the main drivers of the modem area and power consumption. This has recently highlighted the importance of HARQ Buffer Management, that is, of the use of Buffer-aware transmission schemes and of advanced compression policies for the storage of received data. This work investigates HARQ Buffer Management by leveraging information-theoretic achievability arguments based on random coding. Specifically, standard HARQ schemes, namely Type-I, Chase Combining, and Incremental Redundancy, are first studied under the assumption of a finite-capacity HARQ Buffer by considering both coded modulation, via Gaussian signaling, and Bit Interleaved Coded Modulation (BICM). The analysis sheds light on the impact of different compression strategies, namely the conventional compression log-likelihood ratios and the direct digitization of baseband signals, on the throughput. The optimization of coding blocklength is also investigated, highlighting the benefits of HARQ Buffer-aware transmission scheme.
Wonju Lee - One of the best experts on this subject based on the ideXlab platform.
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harq Buffer Management an information theoretic view
International Symposium on Information Theory, 2015Co-Authors: Wonju Lee, Osvaldo Simeone, Joonhyuk Kang, Sundeep Rangan, Petar PopovskiAbstract:A key practical constraint on the design of Hybrid automatic repeat request (HARQ) schemes is the modem chip area that needs to be allocated to store previously received packets. The fact that, in modern wireless standards, this area can amount to a large fraction of the overall chip has recently highlighted the importance of HARQ Buffer Management, that is, of the use of advanced compression policies for storage of received data. This work tackles the analysis of the throughput of standard HARQ schemes, namely Type-I, Chase Combining and Incremental Redundancy, under the assumption of a finite-capacity HARQ Buffer by taking an information-theoretic standpoint based on random coding. Both coded modulation, via Gaussian signaling, and Bit Interleaved Coded Modulation (BICM) are considered. The analysis sheds light on questions of practical relevance for HARQ Buffer Management such as on the type of information to be extracted from the received packets and on how to store it.
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harq Buffer Management an information theoretic view
arXiv: Information Theory, 2015Co-Authors: Wonju Lee, Osvaldo Simeone, Joonhyuk Kang, Sundeep Rangan, Petar PopovskiAbstract:A key practical constraint on the design of Hybrid automatic repeat request (HARQ) schemes is the size of the on-chip Buffer that is available at the receiver to store previously received packets. In fact, in modern wireless standards such as LTE and LTE-A, the HARQ Buffer size is one of the main drivers of the modem area and power consumption. This has recently highlighted the importance of HARQ Buffer Management, that is, of the use of Buffer-aware transmission schemes and of advanced compression policies for the storage of received data. This work investigates HARQ Buffer Management by leveraging information-theoretic achievability arguments based on random coding. Specifically, standard HARQ schemes, namely Type-I, Chase Combining and Incremental Redundancy, are first studied under the assumption of a finite-capacity HARQ Buffer by considering both coded modulation, via Gaussian signaling, and Bit Interleaved Coded Modulation (BICM). The analysis sheds light on the impact of different compression strategies, namely the conventional compression log-likelihood ratios and the direct digitization of baseband signals, on the throughput. Then, coding strategies based on layered modulation and optimized coding blocklength are investigated, highlighting the benefits of HARQ Buffer-aware transmission schemes. The optimization of baseband compression for multiple-antenna links is also studied, demonstrating the optimality of a transform coding approach.
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HARQ Buffer Management: An Information-Theoretic View
IEEE Transactions on Communications, 2015Co-Authors: Wonju Lee, Osvaldo Simeone, Joonhyuk Kang, Sundeep Rangan, Petar PopovskiAbstract:A key practical constraint on the design of hybrid automatic repeat request (HARQ) schemes is the size of the on-chip Buffer that is available at the receiver to store previously received packets. In fact, in modern wireless standards such as LTE and LTE-A, the HARQ Buffer size is one of the main drivers of the modem area and power consumption. This has recently highlighted the importance of HARQ Buffer Management, that is, of the use of Buffer-aware transmission schemes and of advanced compression policies for the storage of received data. This work investigates HARQ Buffer Management by leveraging information-theoretic achievability arguments based on random coding. Specifically, standard HARQ schemes, namely Type-I, Chase Combining, and Incremental Redundancy, are first studied under the assumption of a finite-capacity HARQ Buffer by considering both coded modulation, via Gaussian signaling, and Bit Interleaved Coded Modulation (BICM). The analysis sheds light on the impact of different compression strategies, namely the conventional compression log-likelihood ratios and the direct digitization of baseband signals, on the throughput. The optimization of coding blocklength is also investigated, highlighting the benefits of HARQ Buffer-aware transmission scheme.
J W Mark - One of the best experts on this subject based on the ideXlab platform.
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a Buffer Management scheme for the scoq switch under nonuniform traffic loading
IEEE Transactions on Communications, 1994Co-Authors: D X Chen, J W MarkAbstract:The SCOQ switch is a Batcher-banyan based high performance fast packet switch with shared concentration and output queueing, with a maximum of L( >
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a Buffer Management scheme for the scoq switch under nonuniform traffic loading
International Conference on Computer Communications, 1992Co-Authors: D X Chen, J W MarkAbstract:The SCOQ switch is a Batcher-banyan-based high-performance fast packet switch with shared concentration and output queuing, with a maximum of L( >
J L Zhao - One of the best experts on this subject based on the ideXlab platform.
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Buffer Management for video database systems
International Conference on Data Engineering, 1995Co-Authors: Doron Rotem, J L ZhaoAbstract:Future multimedia information systems are likely to manage thousands of videos with various lengths and display requirements. Mismatch of playback and delivery rates of compressed video data requires sophisticated Buffer Management algorithms to guarantee smooth playback of video data. In this paper, we address some of the many design and operational issues including Buffer size requirements, refreshing policies, and support of multiple access points to the same video object. Three different Buffer Management strategies are proposed and analyzed to minimize the average waiting time while ensuring display without jerkiness. We also evaluate the effectiveness these Buffer Management strategies with a simulation study. >
