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Communication Over Individual Channels

IEEE TRANSACTIONS ON INFORMATION THEORY 2011年第11期57卷 7333-7358页

作者： Lomnitz, Yuval Feder, Meir Tel Aviv Univ Dept Elect Engn Syst IL-69978 Ramat Aviv Israel

A communication problem in considered, where no mathematical model is specified for the channel. The achievable rates are determined as a function of the channel input and output sequences known a-posteriori, without assuming any a-priori relation between them. For discrete channels the empirical mutual information between the input and output sequences is shown to be achievable, while for continuous channels the achievable rate is based on the empirical correlation between the sequences. A rate-adaptive scheme employing feedback which achieves these rates asymptotically with a guaranteed reliability, without prior knowledge of the channel behavior, is presented.

关键词： Channel uncertainty communication feedback communication unknown channels random coding rateless coding

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Push-to-peer video-on-demand system:: Design and evaluation

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2007年第9期25卷 1706-1716页

作者： Suh, Kyoungwon Diot, Christophe Kurose, Jim Massoulie, Laurent Neumann, Christoph Towsley, Don Varvello, Matteo Univ Massachusetts Amherst MA 01003 USA Illinois State Univ Normal IL 61761 USA Thomson Res Lab Paris France Eurecom Sophia Antipolis France

We propose Push-to-Peer, a peer-to-peer system to cooperatively stream video. The main departure from previous work is: that content is proactively pushed to peers, and persistently stored before the actual peer-to-peer transfers. The initial content placement increases content availability and improves the use of peer uplink bandwidth. Our specific contributions are: (i) content placement and associated pull policies that allow the optimal use of uplink bandwidth;(ii) performance analysis of such policies in controlled environments such as DSL networks under ISP control;(iii) a distributed load balancing strategy for selection of serving peers.

关键词： peer-to-peer networks video on demand service push service rateless coding randomized peer selection

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Comprehensive protection of data-partitioned video for broadband wireless IPTV streaming

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MOBILE INFORMATION SYSTEMS 2012年第2期8卷 83-105页

作者： Al-Jobouri, Laith Fleury, Martin Ghanbari, Mohammed Univ Essex Dept CSEE Colchester CO4 3SQ Essex England

This paper examines the threat to video streaming from slow and fast fading, traffic congestion, and channel packet drops. The proposed response is a combination of: rateless channel coding, which is adaptively applied;data-partitioned source coding to exploit prioritized packetization;and duplicate slice provision, which is the focus of the evaluation in this paper. The paper also considers the distribution of intra-refresh macroblocks as a means of avoiding sudden data rate increases. When error bursts occur, this paper shows that duplicate slices are certainly necessary but this provision is more effective for medium quality video than it is for high quality video. The percentage of intra-refresh macroblocks can be low and still reduce the impact of temporal error propagation.

关键词： Data-partitioning error resilience FEC IPTV rateless coding redundant packets video streaming WiMAX

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Throughput Optimization in rateless Coded Cooperative Relay Networks

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IEICE TRANSACTIONS ON COMMUNICATIONS 2012年第5期E95B卷 1810-1814页

作者： James, Ashish Madhukumar, A. S. Adachi, Fumiyuki Nanyang Technol Univ Sch Comp Engn Singapore 639798 Singapore Tohoku Univ Grad Sch Engn Dept Elect & Commun Engn Sendai Miyagi 9808579 Japan

By performing the encoding operation on several message packets, rateless coding in cooperative networks has the potential risk of processing information already available to the receivers. In this paper, the intermediate packet decodability of rateless codes is exploited to mitigate such redundant packet processing at the cooperating nodes. The message packets that are already decoded at the receivers are eliminated from further processing by harnessing the back channel (from receiver to transmitter) for feedback. This reduces the required number of transmissions and optimizes the throughput of the network.

关键词： rateless coding cooperative communication feedback

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Winning by Successive Failures-Enhanced Link Adaptation for Cellular Networks

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IEEE COMMUNICATIONS LETTERS 2023年第7期27卷 1904-1908页

作者： Kutz, Gideon Tillinger, Amit Bar-Or Oved, Tal Landis, Shay Amrani, Ofer Touboul, Assaf Qualcomm Israel WRD Modem Tech Sys IL-4524075 Hod Hasharon Israel Tel Aviv Univ Dept Elect Engn Syst IL-69978 Tel Aviv Israel

Link adaptation algorithm that tailors the data transmission coding-rate to the dynamic channel state is an essential ingredient in any (modern) cellular network. Current link adaptation schemes are based on the usage of periodic pilots sent by the base station. The mobile terminal determines the optimal coding-rate to be employed based on processing the received pilots, and then reports its findings back to the base station. Herein, we show that these schemes perform far from optimal and do not come close to achieving the channel capacity. To address this shortcoming, we propose enhanced link adaptation scheme based on a rateless-like coding approach. According to the proposed scheme, the base station sends multiple re-transmissions, effectively combined at the receiver side, until decoding is successful. It is demonstrated that the proposed scheme can closely track the channel capacity, even for highly mobile terminals, hence achieving significant gains over current link adaptation schemes. From the practical side, we address several implementation-related issues thus paving the way for the adaptation of the proposed scheme to the use of 5G networks.

关键词： Link adpatation rateless coding

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Achievable Rates and Fairness in rateless Coded Relaying Schemes

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IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2008年第11期7卷 4439-4444页

作者： Nikjah, Reza Beaulieu, Norman C. Univ Alberta Dept Elect & Comp Engn Edmonton AB Canada

The average throughput of three decode-and-forward (DF) half-duplex (DFHD) and two DF full-duplex (DFFD) rateless coded relaying schemes are studied under a peak power constraint (PPC) and an average power constraint (APC). Two of the DFHD and one of the DFFD protocols are known. One new, much simpler, DFHD protocol, and one new DFFD protocol are proposed. The fairness in comparing the protocols in terms of energy cost is formulated, and the protocols are compared to each other in a power-fair regime. The two previously proposed DFHD protocols, one of which is superior to the other under the PPC, are found to have almost the same performances when compared power-fairly. The proposed protocols are built upon opportunistic communication and power optimization such that, although inferior to their predecessors in a PPC regime, they can slightly surpass them under the APC.

关键词： Achievable rates decode-and-forward relaying full-duplex relaying half-duplex relaying power fairness rateless coding

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Soft-Switching Hybrid FSO/RF Links Using Short-Length Raptor Codes: Design and Implementation

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IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2009年第9期27卷 1698-1708页

作者： Zhang, Wenzhe Hranilovic, Steve Shi, Ce McMaster Univ Dept Elect & Comp Engn Hamilton ON L8S 4K1 Canada

Free-space optical (FSO) links offer gigabit per second data rates and low system complexity, but suffer from atmospheric loss due to fog and scintillation. Radio-frequency (RF) links have lower data rates, but are relatively insensitive to weather. Hybrid FSO/RF links combine the advantages of both links. Currently, selection or "hard-switching" is performed between FSO or RF links depending on feedback from the receiver. This technique is inefficient since only one medium is used at a time. In this paper, we develop a "soft-switching" scheme for hybrid FSO/RF links using short-length Raptor codes. Raptor encoded packets are sent simultaneously on both links and the code adapts to the conditions on either link with very limited feedback. A set of short-length Raptor codes (k = 16 to 1024) are presented which are amenable to highspeed implementation. A practical Raptor encoder and decoder are implemented in an FPGA and shown to support a 714 Mbps data rate with a 97 mW power consumption and 26360 gate circuit scale. The performance of the switching algorithms is simulated in a realistic channel model based on climate data. For a 1 Gbps FSO link combined with a 96 Mbps WiMAX RF link, an average rate of over 472 Mbps is achieved using the implemented Raptor code while hard-switching techniques achieved 112 Mbps on average.

关键词： Free-space optical (FSO) communication systems hybrid RF/FSO channels optical wireless rateless coding reliability of optical wireless systems

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FMTCP: A Fountain Code-Based Multipath Transmission Control Protocol

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IEEE-ACM TRANSACTIONS ON NETWORKING 2015年第2期23卷 465-478页

作者： Cui, Yong Wang, Lian Wang, Xin Wang, Hongyi Wang, Yining Tsinghua Univ Beijing 100084 Peoples R China SUNY Stony Brook Dept Elect & Comp Engn Stony Brook NY 11794 USA

Ideally, the throughput of a Multipath TCP (MPTCP) connection should be as high as that of multiple disjoint single-path TCP flows. In reality, the throughput of MPTCP is far lower than expected. In this paper, we conduct an extensive simulation-based study on this phenomenon, and the results indicate that a subflow experiencing high delay and loss severely affects the performance of other subflows, thus becoming the bottleneck of the MPTCP connection and significantly degrading the aggregate goodput. To tackle this problem, we propose Fountain code-based Multipath TCP (FMTCP), which effectively mitigates the negative impact of the heterogeneity of different paths. FMTCP takes advantage of the random nature of the fountain code to flexibly transmit encoded symbols from the same or different data blocks over different subflows. Moreover, we design a data allocation algorithm based on the expected packet arriving time and decoding demand to coordinate the transmissions of different subflows. Quantitative analyses are provided to show the benefit of FMTCP. We also evaluate the performance of FMTCP through ns-2 simulations and demonstrate that FMTCP outperforms IETF-MPTCP, a typical MPTCP approach, when the paths have diverse loss and delay in terms of higher total goodput, lower delay, and jitter. In addition, FMTCP achieves high stability under abrupt changes of path quality.

关键词： Fountain code multipath TCP rateless coding scheduling

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rateless Codes for AVC Models

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IEEE TRANSACTIONS ON INFORMATION THEORY 2010年第7期56卷 3105-3114页

作者： Sarwate, Anand D. Gastpar, Michael Univ Calif Berkeley Dept Elect Engn & Comp Sci Berkeley CA 94720 USA Delft Univ Technol Fac Elect Engn Math & Comp Sci EEMCS Delft Netherlands

The arbitrarily varying channel (AVC) is a channel model whose state is selected maliciously by an adversary. Fixed-blocklength coding assumes a worst-case bound on the adversary's capabilities, which leads to pessimistic results. This paper defines a variable-length perspective on this problem, for which achievable rates are shown that depend on the realized actions of the adversary. Specifically, rateless codes are constructed which require a limited amount of common randomness. These codes are constructed for two kinds of AVC models. In the first the channel state cannot depend on the channel input, and in the second it can. As a by-product, the randomized coding capacity of the AVC with state depending on the transmitted codeword is found and shown to be achievable with a small amount of common randomness. The results for this model are proved using a randomized strategy based on list decoding.

关键词： Adversarial models arbitrarily varying channels (AVCs) randomization rateless coding

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A Design of Physical-Layer Raptor Codes for Wide SNR Ranges

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IEEE COMMUNICATIONS LETTERS 2014年第3期18卷 491-494页

作者： Kuo, Shiuan-Hao Guan, Yong Liang Lee, Shih-Kai Lin, Mao-Chao Natl Taiwan Univ Grad Inst Commun Engn Taipei 106 Taiwan Nanyang Technol Univ Sch Elect & Elect Engn Singapore 639798 Singapore Yuan Ze Univ Dept Commun Engn Tao Yuan 32003 Taiwan Natl Taiwan Univ Dept Elect Engn Taipei 106 Taiwan

It is known that the Raptor code can be constructed to achieve a rate close to the capacity of the binary-input AWGN (BIAWGN) channel with a fixed signal-to-noise ratio (SNR). In this letter, we propose a constructive approach of designing the Raptor code over the BIAWGN channel such that the achieved rates are close to the associated capacities for wide SNR ranges.

关键词： rateless coding Raptor code channel capacity

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