检索结果-内蒙古大学图书馆

IEEE TRANSACTIONS ON COMMUNICATIONS 2011年第6期59卷 1563-1569页

作者： Maiya, Shashank V. Fuja, Thomas E. Univ Notre Dame Dept Elect Engn Notre Dame IN 46556 USA

This paper introduces a new approach to cooperative communications. Consider two partner nodes that cooperate to convey their data to a common destination, each transmitting not only its own "local" data but also acting as a relay for its partner, thereby effecting spatial diversity. In the proposed scheme, each partner multiplexes local data with relayed data and convolutionally encodes the resulting bitstream prior to transmission;the other partner then uses its knowledge of the relayed data to prune edges from the code trellis, thereby decoding at a lower (and more robust) rate. The destination observes two copies of each source's data - one transmitted as local information, the other transmitted as relayed information - and employs iterative decoding to recover the same. The resulting performance is superior to that of cooperation schemes based on time sharing - for example, a gain of 4.1 dB is observed at a frame-error rate of 10(-3) with memory M = 3 codes - as well as schemes employing the newer algebraic superposition approach of Xiao et al., with trellis pruning enjoying an advantage of 0.55 dB to 1.04 dB over algebraic superposition, depending on M. The new approach requires some additional decoding complexity at each partner node, but the decoding complexity at the destination node is kept constant.

关键词： Cooperative systems fading channels error correction coding diversity methods

来源：评论

学校读者我要写书评

暂无评论

Optimal and near-optimal encoders for short and moderate-length tail-biting trellises

引用

IEEE TRANSACTIONS ON INFORMATION THEORY 1999年第7期45卷 2562-2571页

作者： Ståhl, P Anderson, JB Johannesson, R Lund Univ Dept Informat Technol Informat Theory Grp S-22100 Lund Sweden

The results of an extensive search for short and moderate-length polynomial convolutional encoders for time-invariant tail-biting representations of block codes at rates R = 1/4, 1/3, 1/2, and 2/3 are reported, The fa... 详细信息

关键词： convolutional codes error correction coding tail-biting encoders trellis codes

来源：评论

学校读者我要写书评

暂无评论

Efficient Hardware Architectures and Implementations of Packet-Level Erasure coding Schemes for High Data Rate Reliable Satellite Communications

引用

IEEE TRANSACTIONS ON AEROSPACE AND ELECTRONIC SYSTEMS 2022年第3期58卷 2269-2280页

作者： Theodoropoulos, Dimitris Kranitis, Nektarios Tsigkanos, Antonis Machairas, Elias Paschalis, Antonios Natl & Kapodistrian Univ Athens Dept Informat & Telecommun Athens 15784 Greece Natl & Kapodistrian Univ Athens Dept Aerosp Sci & Technol Evripos Univ Complex NKUA Athens 34400 Greece

Forward error correction coding schemes have been used extensively in order to provide continuous and reliable telemetry data transfer from satellites to ground stations and guarantee reliable communications even at low signal-to-noise ratio regimes, where burst errors are dominant. Nevertheless, conventional bit-level channel coding can fail to provide downlink reliability against long error bursts in future high data rate radio frequency and optical (laser) links, especially when automatic repeat queuing strategies are either problematic or impossible due to specific service delay constraints. Packet-level erasure coding has been considered by the Consultative Committee for Space Data Systems (CCSDS) in CCSDS 131.5-O-1 experimental specification for application in high data rate near-earth and deep-space communications, since it can protect against long error bursts as they may come along with the effect of scintillation outages or transmission errors. Implementations of packet-level encoding and decoding so far exist only in software, running on a general-purpose CPU. In this article, we introduce and compare analytical descriptions of packet-level encoding algorithms suitable for hardware implementations. Based on these algorithmic descriptions, we introduce, for the first time, architectures for hardware acceleration of these functions that allow integration on a high-speed on-board data-processing chain with very low footprint. We validate our hardware implementations and demonstrate the efficiency of the proposed architectures on a Xilinx KCU105 development board, which is built around the commercial equivalent of a space-grade field-programmable gate array device. Apart from offloading packet-level encoding from the on-board embedded processor, the proposed accelerators achieve a significant speedup (over 80 times), when compared with on-board software implementations, by porting on some of the most commonly used and state-of-the-art space-qualified embedded

关键词： Codes Encoding Parity check codes Software Field programmable gate arrays Standards Forward error correction Encoding error correction coding field-programmable gate arrays (FPGAs) forward error correction (FEC) satellite communication on-board systems

来源：评论

学校读者我要写书评

暂无评论

Hybrid Optical/RF Channel Performance Analysis for Turbo Codes

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 2011年第5期59卷 1389-1399页

作者： Tapse, Hrishikesh Borah, Deva K. Perez-Ramirez, Javier New Mexico State Univ Klipsch Sch Elect & Comp Engn Las Cruces NM 88003 USA

Turbo coded data transmission over a hybrid channel, consisting of parallel free space optical (FSO) and radio frequency (RF) links, is considered, and analytical bit error performance results are derived. The FSO link is modeled using the gamma-gamma distribution function, and both random and block fading channels are used. Random and specific codeword bit selections for transmission through the RF link are considered. Conditions to guarantee bit error rate (BER) performance improvement in hybrid channels over FSO only links are derived. In the case of block fading channels, the hybrid channel using turbo codes is found to provide several dBs of gain in the signal-to-noise ratio (SNR) over an optical only link. A technique to jointly optimize puncturing and RF bit selection patterns for the hybrid channel is also presented. Results demonstrate significant BER performance improvement obtained from the proposed joint optimization approach.

关键词： Optical communications on-off keying intensity modulation error correction coding iterative methods

来源：评论

学校读者我要写书评

暂无评论

A code division multiplexing scheme for satellite digital audio broadcasting

引用

IEEE JOURNAL ON SELECTED AREAS IN COMMUNICATIONS 1999年第11期17卷 1985-1998页

作者： Weerackody, V Lou, HL Sayeed, Z Lucent Technol Bell Labs Murray Hill NJ 07974 USA

Currently, several systems are being considered for digital audio broadcasting (DAB) and some of these systems will be deployed for commercial use in the near future. In this paper, we consider a code division multiplex (CDM) scheme for satellite DAB, For diversity purposes, this system makes use of at least two satellites, and in urban areas, where the satellite signals are shadowed by large structures, a terrestrial network is employed. We present a forward error protection (FEC) scheme that is robust under a variety of channel conditions, especially in cases where the received signal is severely attenuated because of highway underpasses and tunnels, This FEC scheme makes use of time diversity, and this introduces a large delay. Such delays will not affect the performance of broadcast systems;however, the delay will be an issue during tuning when a switch to another channel occurs. We introduce a separate low-delay low-rate tuning channel to facilitate tuning, Extensive simulation results are given to examine the performance of the system, and it is shown that about 70 audio channels, each with a rate of 96 kbit/s, can be satisfactorily supported in a bandwidth of approximately 12.5 MHz in most of the channel conditions considered.

关键词： broadcasting code division multiple access (CDMA) error correction coding

来源：评论

学校读者我要写书评

暂无评论

Real-time video compression system design and hardware implementation based on multiple ADV212

引用

High Technology Letters 2016年第3期22卷 282-287页

作者：徐冬冬 Wang Wenhua Zhang Yu Zhang Xingxiang Fu Tianjiao Ren Jianyue Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Scienses Changchun 130033 P. R. China University of Chinese Academy of Sciences Beijing 100039 P. R. China

In order to improve the transmission rate of the compression system,a real-time video lossy compression system based on multiple ADV212 is proposed and achieved. Considering the CMOS video format and the working principle of ADV212,a Custom-specific mode is used for various video formats firstly. The data can be cached through the FPGA internal RAM and SDRAM Ping-Pong operation. And the working efficiency is greatly promoted. Secondly,this method can realize direct code stream transmission or do it after storage. Through the error correcting coding,the correction ability of the flash memory is highly improved. Lastly,the compression and de-compression circuit boards are involved to specify the performance of the method. The results show that the compression system has a real-time and stable performance. And the compression ratio can be changed arbitrarily by configuring the program. The compression system can be realized and the real-time performance is good with large amount of data.

关键词： compression system ADV212 Custom-specific Ping-Pong operation error correction coding

来源：评论

学校读者我要写书评

暂无评论

Redundancy Minimizing Techniques for Robust Transmission in Wireless Networks

引用

JOURNAL OF COMMUNICATIONS AND NETWORKS 2009年第6期11卷 564-573页

作者： Kacewicz, Anna Wicker, Stephen B. Cornell Univ Sch Elect & Comp Engn Ithaca NY 14853 USA

In this paper, we consider a wireless multiple path network in which a transmitting node would like to send a message to the receiving node with a certain probability of success. These two nodes are separated by N erasure paths, and we devise two algorithms to determine minimum redundancy and optimal symbol allocation for this setup. We discuss the case with N = 3 and then extend the case to an arbitrary number of paths. One of the algorithms minimum redundancy algorithm in exponential time is shown to be optimal in several cases, but has exponential running time. The other algorithm, minimum redundancy algorithm in polynomial time, is sub-optimal but has polynomial worst-case running time. These algorithms are based off the theory of maximum-distance separable codes. We apply the MRAET algorithm on maximum-distance separable, Luby transform, and Raptor codes and compare their performance.

关键词： error correction coding multiple path channels networks redundancy robustness

来源：评论

学校读者我要写书评

暂无评论

Demonstration of Optical FEC coding Scheme With Convolutional Code Consisting of a Signal Source

引用

IEEE PHOTONICS TECHNOLOGY LETTERS 2017年第1期29卷 165-168页

作者： Aikawa, Yohei Uenohara, Hiroyuki Tokyo Inst Technol Lab Future Interdisciplinary Res Sci & Technol Yokohama Kanagawa 2268503 Japan

In this letter, we experimentally demonstrated an all-optical forward error correction (FEC) coding scheme with the (7, 5)(8) convolutional code using a single signal source to compensate time-dependent noise. The proposed coding scheme was comprised of optical XOR gates, delay lines, and optical wavelength converters, which are based on four-wave mixing in highly non-linear fibers. The temporal waveforms of the optical FEC coding scheme were experimentally achieved for 10 Gb/s return-to-zero differential phase shift keying (RZ-DPSK) signals modulated with 2(23)-1, and the obtained idler signals accurately corresponded to the (7, 5)(8) code between any input signals. Under the optimized conditions of operational wavelengths, the proposed scheme theoretically offered 4.0 and 3.5 dB net coding gains for the conditions of BER >= 10(-8) and BER = 10(-9), respectively, owing to its small power penalties.

关键词： error correction coding optical signal processing optical FEC coding optical logic system

来源：评论

学校读者我要写书评

暂无评论

Communication method between spectrum heterogeneous secondary users in OFDM-based cognitive radio

引用

ELECTRONICS LETTERS 2011年第14期47卷 827-U66页

作者： Ko, J. Kim, C. Pohang Univ Sci & Technol Dept Comp Sci & Engn Pohang Gyungbuk South Korea

A method that facilitates message exchange between spectrum heterogeneous secondary users in OFDM-based cognitive radio networks is presented. The proposed method utilises error correction coding to address spectrum h... 详细信息

关键词： cognitive radio wireless channels control channel error correction codes spectrum heterogeneous secondary user message exchange Codes communication method OFDM-based cognitive radio network radio spectrum management error correction coding Radio links and equipment OFDM modulation

来源：评论

学校读者我要写书评

暂无评论

Digital image watermarking based on multiresolution decomposition

引用

ELECTRONICS LETTERS 2000年第13期36卷 1108-1110页

作者： Niu, XM Lu, ZM Sun, SH Harbin Inst Technol Dept Automat Test & Control Harbin 150001 Peoples R China

A multiresolution watermarking method with grey-level watermarking is presented. Both the watermark and the original image are decomposed into three-level multiresolution structures using different mechanisms. The decomposed watermark information is further coded by error correction coding. Each level of watermark information is embedded into the corresponding level of the transformed image. Experimental results show that the proposed algorithm is robust against common image manipulations.

关键词： discrete wavelet transforms industrial property grey-level watermarking Integral transforms in numerical analysis image manipulations error correction codes digital image watermarking three-level multiresolution structures Image and video coding image coding Video signal processing transformed image multiresolution decomposition error correction coding DWT image sequences

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：