检索结果-内蒙古大学图书馆

Cooperation in the Low Power Regime for the MAC Using Multiplexed rateless Codes

IEEE TRANSACTIONS ON SIGNAL PROCESSING 2010年第9期58卷 4720-4734页

作者： Uppal, Momin Yang, Zigui Host-Madsen, Anders Xiong, Zixiang Texas A&M Univ Dept Elect & Comp Engn College Stn TX 77843 USA Availink Inc Germantown MD 20874 USA Univ Hawaii Manoa Dept Elect Engn Honolulu HI 96822 USA

In this paper, we consider cooperation in the low power (low SNR) regime for the multiple access channel with the assumption that the transmitters have no channel state information. A relevant performance measure to consider is therefore the outage capacity. We develop cooperation methods based on multiplexed coding in conjunction with rateless codes and find the achievable rates and in particular the minimum energy per bit required to achieve a certain outage probability. We consider two modes of operation: full duplex [code-division multiple access (CDMA)], where nodes can transmit and receive simultaneously on the same frequency band, and half duplex [frequency-division multiple access (FDMA)], where the nodes transmit and listen on different frequency bands. We show that, perhaps surprisingly, there is little loss in performance when using FDMA. Furthermore, our results show that multiplexed rateless codes come within 0.1 dB of the outer bound on capacity. We also develop practical rateless coding methods for FDMA using multiplexed Raptor codes which operate within 0.52 and 1.1 dB of the theoretical limit for the two-and four-user case, respectively.

关键词： Minimum energy per bit multiplexed coding outage capacity rateless coding the MAC user cooperation

来源：评论

学校读者我要写书评

暂无评论

Distributed secure transmission for covert communication under multi-user network

引用

IET COMMUNICATIONS 2022年第16期16卷 1901-1911页

作者： Huang, Ying Lei, Jing Natl Univ Def Technol Coll Elect Sci & Technol Changsha Hunan Peoples R China

In order to counter the double attack with wardens and eavesdroppers in the practical scenario, a distributed transmission scheme with security and covertness is proposed, which combines coding techniques and transmission protocol. The covert message is encoded by rateless codes and transmitted embedded in normal frames. The security is based on the random essence of rateless coding, and the covertness is achieved by ignoring the error frames and maintaining the signal waveform. The inter-collusion between multiple wardens and eavesdroppers greatly increases the potential security hazards, which is first discussed in this paper. The authors can counter the inter-collusion attack by adjusting the ratio of covert frame transmission in the distributed transmission scheme with security and covertness. Compared with the related work, this paper has many advantages, such as good robustness, lower extra complexity, and the insurance of the performance for both normal message and covert message. The analysis and simulation results show that our distributed transmission scheme with security and covertness can achieve both covertness and security based on the effective design under the existing communication system.

关键词： transmission protocol distributed transmission scheme wireless channels protocols encoding covert communication eavesdroppers covertness multiple wardens distributed secure transmission potential security hazards multiuser network error frames inter-collusion attack normal frames telecommunication security covert frame transmission covert message rateless coding double attack

来源：评论

学校读者我要写书评

暂无评论

Analysis and Optimization of a rateless Coded Joint Relay System

引用

IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS 2010年第3期9卷 1175-1185页

作者： Gong, Chen Yue, Guosen Wang, Xiaodong Columbia Univ Dept Elect Engn New York NY 10027 USA NEC Labs Amer Inc Princeton NJ 08540 USA

We consider the code design for a half-duplex 4-node joint relay system with two sources, one relay, and one destination. The relay combines the information from both sources and transmits it to the destination together with both sources. We consider two coding schemes for information combining at the relay, namely, the superposition coding (SC) and the Raptor coding (RC). The Raptor codes are employed at the sources as well as the relay. The relay and the destination perform iterative a posteriori probability (APP) detection and soft Raptor decoding. For both SC and RC, the profiles for Raptor codes are optimized based on the extrinsic information transfer (EXIT) function analysis. For both the additive white Gaussian noise (AWGN) and block fading channels, the joint relay system with optimized profiles exhibits significant performance gains over that employing the code profile optimized for either the single-user AWGN channel or the 2-user multiple-access channel.

关键词： Cooperative communication relay rateless coding raptor codes multiple-access channel half-duplex

来源：评论

学校读者我要写书评

暂无评论

A Reliable Geocast Routing Protocol for Vehicular Ad Hoc Networks

引用

WIRELESS PERSONAL COMMUNICATIONS 2015年第1期83卷 281-295页

作者： Rezaeifar, Zeinab Hendessi, Faramarz Ghahfarokhi, Behrouz Shahgholi Gulliver, T. Aaron Hanyang Univ Dept Comp Sci & Engn Seoul 133791 South Korea Isfahan Univ Technol Dept Elect & Comp Engn Esfahan Iran Univ Isfahan Fac Comp Engn Esfahan Iran Univ Victoria Dept Elect & Comp Engn STN CSC Victoria BC V8W 2Y2 Canada

In addition to safety applications, new Vehicular Ad-Hoc Network (VANET) applications such as onboard entertainment and traffic management are rapidly being developed. This has made geocast, i.e. the transmission of data over a geographic area, an important research topic. Often geocast is done over wide and distant areas, which can result in significant overhead. In this paper, existing VANET routing protocols are investigated from a geocast perspective. To address the shortcomings of these methods in addressing both overhead and packet delivery ratio issues in geocast routing, two enhanced mechanisms are introduced based on the AODV routing protocol. Unicast routing is employed in the proposed protocols to transmit data to the destination region, and then flooding is used within the region for data dissemination. Furthermore, rateless coding and link layer notifications are used to improve the delivery ratio. The proposed methods are compared with existing flooding based geocast routing and Inter Vehicle Geocast (IVG) routing. Results are presented for an urban environment in terms of delay, overhead, and message delivery. These results show that the proposed approach significantly reduces the overhead and increases the delivery ratio with a minimal increase in delay.

关键词： Vehicular Ad-Hoc Network (VANET) Routing Geocast AODV rateless coding

来源：评论

学校读者我要写书评

暂无评论

Universal Communication-Part I: Modulo Additive Channels

引用

IEEE TRANSACTIONS ON INFORMATION THEORY 2013年第9期59卷 5488-5510页

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

Which communication rates can be attained over a channel whose output is an unknown (possibly stochastic) function of the input that may vary arbitrarily in time with no a priori model? Following the spirit of the finite-state compressibility of a sequence, defined by Lempel and Ziv, a "capacity" is defined for such a channel as the highest rate achievable by a designer knowing the particular relation that indeed exists between the input and output for all times, yet is constrained to use a fixed finite-length block communication scheme without feedback, i.e., use the same encoder and decoder over each block. In the case of the modulo additive channel, where the output sequence is obtained by modulo addition of an unknown individual sequence to the input sequence, this capacity is upper bounded by a function of the finite state compressibility of the noise sequence. A universal communication scheme with feedback that attains this capacity universally, without prior knowledge of the noise sequence, is presented.

关键词： Arbitrarily varying channels (AVCs) feedback communication individual sequences rateless coding universal communication unknown channels

来源：评论

学校读者我要写书评

暂无评论

Unequal error protection for data partitioned H.264/AVC video broadcasting

引用

MULTIMEDIA TOOLS AND APPLICATIONS 2015年第15期74卷 5787-5809页

作者： Nazir, Sajid Vukobratovic, Dejan Stankovic, Vladimir Andonovic, Ivan Nybom, Kristian Gronroos, Stefan Univ Strathclyde Dept EEE Glasgow Lanark Scotland Univ Novi Sad Dept Power Elect & Commun Engn Novi Sad 21000 Serbia Abo Akad Univ Turku Finland

Application Layer Forward Error Correction (AL-FEC) is becoming a popular addition to protocols for real-time video delivery over IP-based wireless networks. In particular, rateless codes are identified as suitable solution for AL-FEC due to their flexibility and capacity-approaching performance. Since each part of video data is not equally important for video reconstruction, it is beneficial to group it based on its importance, and then provide different degree of protection using Unequal Error Protection (UEP). Data partitioning (DP) is one such low-cost feature in H.264/AVC enabling partitioning of video data based on its importance. We propose schemes for the DP H.264/AVC video transmission using Raptor and Random Linear Codes (RLC) and investigate their performance as AL-FEC solutions in Digital Video Broadcasting. We provide comparisons between optimized Non-Overlapping Window RLC and Expanding Window (EW) RLC, which are two effective UEP RLC strategies. The results using realistic channel traces show viability of the EW RLC as a promising solution for multimedia broadcast applications.

关键词： Video compression rateless coding Digital Video Broadcasting Joint source-channel coding

来源：评论

学校读者我要写书评

暂无评论

An Efficient rateless Scheme Based on the Extendibility of Systematic Polar Codes

引用

IEEE ACCESS 2017年 5卷 23223-23232页

作者： Feng, Bowen Zhang, Qinyu Jiao, Jian Harbin Inst Technol Commun Engn Res Ctr Shenzhen 518055 Guangdong Peoples R China

In this paper, a new rateless scheme based on the extendibility of systematic polar codes is proposed, which is applicable for the scenario without channel state information (CSI). With detailed analyses on the existing rateless schemes, we obtain the drawbacks and difficulties which can make the schemes dysfunctional. We expound the extendibility of systematic polar codes elaborately, which forms the basis of the new rateless scheme. In addition, with the incremental redundancy hybrid automatic repeat request transmission, the new rateless scheme is established. The construction of polar codes specialized for the new scheme is also proposed, which can provide reliable performance. Comparing with the existing rateless schemes, the new scheme can be applied for arbitrary channels efficiently and reliably.

关键词： Systematic polar codes rateless coding IR-HARQ construction

来源：评论

学校读者我要写书评

暂无评论

Decoding Delay Performance of Random Linear Network coding for Broadcast

引用

IEEE TRANSACTIONS ON VEHICULAR TECHNOLOGY 2017年第8期66卷 7050-7060页

作者： Chatzigeorgiou, Ioannis Tassi, Andrea Univ Lancaster Sch Comp & Commun InfoLab21 Lancaster LA1 4WA England Univ Bristol Dept Elect & Elect Engn Bristol BS8 1TH Avon England

Characterization of the delay profile of systems employing random linear network coding is important for the reliable provision of broadcast services. Previous studies focused on network coding over large finite fields or developed Markov chains to model the delay distribution but did not look at the effect of transmission deadlines on the delay. In this paper, we consider generations of source packets that are encoded and transmitted over the erasure broadcast channel. The transmission of packets associated with a generation is taken to be deadline constrained, that is, the transmitter drops a generation and proceeds to the next one when a predetermined deadline expires. Closed-form expressions for the average number of required packet transmissions per generation are obtained in terms of the generation size, the field size, the erasure probability, and the deadline choice. An upper bound on the average decoding delay, which is tighter than previous bounds found in the literature, is also derived. Analysis shows that the proposed framework can be used to fine-tune the system parameters and ascertain that neither insufficient nor excessive amounts of packets are sent over the broadcast channel.

关键词： Broadcast delay multicast network coding non-systematic probability analysis rateless coding systematic

来源：评论

学校读者我要写书评

暂无评论

Extreme Value FEC for Reliable Broadcasting in Wireless Networks

引用

IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 2010年第7期28卷 1180-1189页

作者： Xiao, Weiyao Starobinski, David Boston Univ Dept Elect & Comp Engn Boston MA 02215 USA

The advent of practical rateless codes enables implementation of highly efficient packet-level forward error correction (FEC) strategies for reliable data broadcasting in loss-prone wireless networks, such as sensor networks. Yet, the critical question of accurately quantifying the proper amount of redundancy has remained largely unsolved. In this paper, we exploit advances in extreme value theory to rigorously address this problem. Under the asymptotic regime of a large number of receivers, we derive a closed-form expression for the cumulative distribution function (CDF) of the completion time of file distribution. We show the existence of a phase transition associated with this CDF and accurately locate the transition point. We derive tight convergence bounds demonstrating the accuracy of the asymptotic estimate for the practical case of a finite number of receivers. Further, we asymptotically characterize the CDF of the completion time under heterogeneous packet loss, by establishing a close relationship between the data broadcasting and multi-set coupon collector problems. We demonstrate the benefits of our approach through simulation and through real experiments on a Tmote Sky sensor testbed. Specifically, we augment the existing rateless Deluge software dissemination protocol with an extreme value FEC strategy. The experimental results reveal reduction by a factor of five in retransmission request messages and by a factor of two in total dissemination time, at the cost of a marginally higher number of data packet transmissions in the order of 5%.

关键词： Extreme Value Theory Coupon Collector's Problem Forward Error Correction (FEC) rateless coding Over-the-Air Programming

来源：评论

学校读者我要写书评

暂无评论

Decoding of LT-Like Codes in the Absence of Degree-One Code Symbols

引用

ETRI JOURNAL 2016年第5期38卷 896-902页

作者： Abdulkhaleq, Nadhir I. Gazi, Orhan Cankaya Univ Dept Elect & Commun Ankara Turkey

Luby transform (LT) codes were the first practical rateless erasure codes proposed in the literature. The performances of these codes, which are iteratively decoded using belief propagation algorithms, depend on the degree distribution used to generate the coded symbols. The existence of degree-one coded symbols is essential for the starting and continuation of the decoding process. The absence of a degree-one coded symbol at any instant of an iterative decoding operation results in decoding failure. To alleviate this problem, we proposed a method used in the absence of a degree-one code symbol to overcome a stuck decoding operation and its continuation. The simulation results show that the proposed approach provides a better performance than a conventional LT code and memory-based robust soliton distributed LT code, as well as that of a Gaussian elimination assisted LT code, particularly for short data lengths.

关键词： rateless coding LT erasure codes Degree-one Tanner graph pattern recognition

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：