检索结果-内蒙古大学图书馆

On error-correction coding for CDMA PON

JOURNAL OF LIGHTWAVE TECHNOLOGY 2005年第8期23卷 2342-2351页

作者： Lundqvist, H Karlsson, G KTH Royal Inst Technol Lab Commun Networks S-16440 Kista Sweden

Optical-code-division multiple access (OCDMA) has been investigated as a multiple-access technique for a long time, but so far, it has not reached any practical success. We investigate the performance of low-complexity OCDMA systems with a realistic model of noise and interference;the main limitation of the system is beat noise. To improve the performance, we consider forward-error correction (FEC) and soft decoding using standard error-correcting codes. The achievable error rates are evaluated using simulations and show significant improvement when FEC is used. The results also show that frequency-hopping systems perform better than temporally coded systems when beat noise is taken into accound.

关键词： beat noise error-correction coding optical-code-division multiple access (OCDMA) soft decoding

来源：评论

学校读者我要写书评

暂无评论

Joint Crosstalk-Avoidance and error-correction coding for Parallel Data Buses

引用

IEEE TRANSACTIONS ON INFORMATION THEORY 2019年第3期65卷 1626-1638页

作者： Niesen, Urs Kudekar, Shrinivas Qualcomm NJ Res Ctr Bridgewater NJ 08807 USA

Communication in integrated circuits faces two major impediments: inter-wire capacitive coupling and noise. coding can be used to address both these problems. So-called crosstalk-avoidance codes mitigate capacitive coupling, and traditional error-correction codes introduce resilience against channel errors. Unfortunately, crosstalk-avoidance and error-correction codes cannot be combined in a straightforward manner. On the one hand, crosstalk-avoidance encoding followed by error-correction encoding destroys the crosstalk-avoidance property. On the other hand, error-correction encoding followed by crosstalk-avoidance encoding causes the crosstalk-avoidance decoder to fail in the presence of errors. Existing approaches circumvent this difficulty by using additional bus wires to protect the parities generated from the output of the error-correction encoder, and are therefore inefficient. In this paper, we propose a novel joint crosstalk-avoidance and error-correction coding and decoding scheme that provides higher bus transmission rates compared with existing approaches. Our joint approach carefully embeds the parities such that the crosstalk-avoidance property is preserved. We analyze the rate and minimum distance of the proposed scheme. We also provide a density evolution analysis and predict iterative decoding thresholds for reliable communication under random bus erasures. This density evolution analysis is nonstandard, since the crosstalk-avoidance constraints are inherently nonlinear.

关键词： Crosstalk-avoidance coding density evolution error-correction coding irregular repeat-accumulate codes on-chip communication

来源：评论

学校读者我要写书评

暂无评论

Enhancement of error-correction coding of Spatial Watermarks for JPEG Compression

Enhancement of Error-Correction Coding of Spatial Watermarks...

引用

8th International Conference on Signal Image Technology and Internet Based Systems (SITIS)

作者： Kimoto, Tadahiko Toyo Univ Fac Sci & Engn Kawagoe Saitama Japan

ISBN: (纸本)9780769549118

This paper demonstrates how channel coding can improve the robustness of spatial image watermarks against JPEG DCT-based compression. Two error-correction coding (ECC) schemes are used here. One scheme, referred to as the vertical ECC (VECC), is to encode information bits in pixel levels by error-correction coding where the Gray code is used to improve the performance. The other scheme, referred to as the horizontal ECC (HECC), is to encode information bits in an image plane by error-correction coding. VECC is also used to encode the code bits of HECC in pixels. Simple single-error-correcting block codes are used in VECC and HECC. Several experiments of these schemes were conducted on test images. The result demonstrates that the error-correcting performance of HECC depends on that of VECC, and accordingly, HECC enhances the capability of VECC. Consequently, HECC with appropriate codes can achieve stronger robustness to JPEG-caused distortions than nonchannel-coding watermarking schemes.

关键词： Digital watermark spatial domain JPEG DCT compression error-correction coding Gray code

来源：评论

学校读者我要写书评

暂无评论

Cooperative coding for wireless networks

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 2004年第9期52卷 1470-1476页

作者： Stefanov, A Erkip, E Polytech Univ Dept Elect & Comp Engn Brooklyn NY 11201 USA

User cooperation represents an effective way of introducing diversity in wireless networks. Spatial diversity gains are obtained through the cooperative use of antennas belonging to several nodes. We design and analyze the performance of channel codes that are capable of achieving the full diversity provided by user cooperation, with the constraint that they also provide the best possible performance in the interuser link. We show that even though the interuser channel is noisy, the codes provide substantial diversity and coding gains over the noncooperative case.

关键词： diversity methods error-correction coding fading channels multiple-input/multiple-output (MIMO) systems

来源：评论

学校读者我要写书评

暂无评论

Multilevel Reed-Solomon Codes for PMR Channels

引用

IEEE TRANSACTIONS ON MAGNETICS 2016年第2期52卷 1-8页

作者： Demirkan, Ismail Silvus, Gregory Istanbul Sehir Univ TR-34662 Istanbul Turkey Broadcom Corp Longmont CO 80503 USA

Reed-Solomon (RS) codes are commonly utilized in magnetic recording systems to correct error bursts. A soft-output Viterbi algorithm (SOVA) is a commonly used detector to provide soft information to error-correcting decoders. We propose a novel architecture of a multilevel interleaved RS coding scheme that not only provides better performance but also has less complexity than an equivalent RS code. This architecture implements an error event detector using the soft information generated by the SOVA detector. The performance and complexity of the decoding technique are compared with the well-known soft-decoding techniques, such as generalized minimum distance decoding and Chase decoding techniques.

关键词： Chase decoding error-correction coding generalized minimum distance (GMD) decoding interleaved coding multilevel coding perpendicular magnetic recording (PMR) Reed-Solomon (RS) codes soft-output Viterbi algorithm (SOVA)

来源：评论

学校读者我要写书评

暂无评论

SOME CODES FOR CORRECTING AND DETECTING UNIDIRECTIONAL BYTE errorS

引用

IEEE TRANSACTIONS ON COMPUTERS 1993年第5期42卷 547-552页

作者： SAITOH, Y IMAI, H YOKOHAMA NATL UNIV FAC ENGNDIV ELECT & COMP ENGNHODOGAYA KUYOKOHAMAKANAGAWA 240JAPAN

Codes for correcting and detecting unidirectional byte errors are investigated. We derive the relations between distances and the error-correcting and -detecting capabilities of such codes. We show that a 2-fold unidirectional b-bit-byte error-correcting (2-UbEC) code requires at least three check bytes and that a 1-fold unidirectional b-bit-byte error-correcting/2-fold unidirectional b-bit-byte error-detecting (1-UbEC/2-UbED) code requires at least two check bytes. Construction methods for 2-UbEC codes with three check bytes and 1-UbEC/2-UbED codes with two check bytes are proposed.

关键词： BYTE errorS coding DEcoding error-correction coding error-DETECTION coding MEMORY FAULT TOLERANCE UNIDIRECTIONAL errorS

来源：评论

学校读者我要写书评

暂无评论

System-Level Design Space Exploration Methodology for Energy-Efficient Sensor Node Configurations: An Experimental Validation

引用

IEEE TRANSACTIONS ON COMPUTER-AIDED DESIGN OF INTEGRATED CIRCUITS AND SYSTEMS 2012年第4期31卷 586-596页

作者： Chouhan, Sonali Balakrishnan, M. Bose, Ranjan Indian Inst Technol Guwahati Dept Elect & Elect Engn Gauhati 781039 Assam India Indian Inst Technol Delhi Dept Comp Sci & Engn New Delhi 110016 India Indian Inst Technol Delhi Dept Elect Engn New Delhi 110016 India

For sensor nodes deployed at small distances, computation energy along with radio energy determines the battery life. We have proposed a system-level design space exploration methodology in [1] for searching an energy-efficient error-correcting code (ECC). This methodology takes into account the computation and the radio energy in an integrated manner. In this paper, we validate this methodology by deploying the Imote2 nodes and measuring energy values under different operating modes, e.g., with and without ECC. In this process, we propose a validation framework and node energy model. Experimental results validate the methodology and show that with ECC we can save up to 14% transmitter energy under a certain set of conditions. The main contribution of this paper is that it establishes experimentally that our methodology is effective in exploration of various node configurations and finding an energy-efficient solution.

关键词： Communication systems design methodology energy management energy measurement error-correction coding modeling

来源：评论

学校读者我要写书评

暂无评论

Performance Analysis of the IEEE 802.15.4a UWB System

引用

IEEE TRANSACTIONS ON COMMUNICATIONS 2009年第5期57卷 1474-1485页

作者： Ahmadian, Zahra Lampe, Lutz Univ British Columbia Dept Elect & Comp Engn Vancouver BC V5Z 1M9 Canada

The recently approved IEEE 802.15.4a standard defines an ultra-wideband (UWB) based physical layer using concatenated coding with mixed binary phase-shift keying and binary pulse-position modulation (BPSK-BPPM) and direct-sequence spreading with time hopping. The concatenated code consists of an outer Reed-Solomon (RS) and an inner convolutional code, and the coding and modulation are combined such that both coherent and noncoherent receiver architectures are supported. In this paper, the error-rate performance of IEEE 802.15.4a compliant UWB radios is investigated. To this end, semi-analytical expressions for the bit-error rate (BER) and frame-error rate (FER) of the coded UWB system are derived. The presented framework is comprehensive in that (i) different methods for generating reliability information (i.e., decoding metrics), (ii) the effects of suboptimal multipath combining, and (iii) coherent and noncoherent reception methods are included. Furthermore, a particularly suited errors-and-erasures RS decoding scheme is devised. The evaluation of the error-rate expressions together with simulation results for realistic UWB channels show that (i) the error-rate approximations are tight over wide ranges of BER and FER, (ii) symbol-wise metrics are clearly advantageous over bit-wise metrics for decoding of the convolutional code, (iii) combining the 5 to 10 strongest multipath components approaches the performance of full combining within 1-2 dB for residential and 3-5 dB for outdoor UWB environments, and (iv) the simplicity of noncoherent detection comes at loss of more than 10 dB in signal-to-noise ratio compared to coherent detection.

关键词： Ultra-wideband (UWB) impulse radio (IR) IEEE 802.15.4a standard pulse-position modulation (PPM) error-correction coding RAKE receiver energy detection

来源：评论

学校读者我要写书评

暂无评论

The development of turbo and LDPC codes for deep-space applications

引用

PROCEEDINGS OF THE IEEE 2007年第11期95卷 2142-2156页

作者： Andrews, Kenneth S. Divsalar, Dariush Dolinar, Sam Hamkins, Jon Jones, Christopher R. Pollara, Fabrizio CALTECH Pasadena CA 91109 USA

The development of error-correcting codes has been closely coupled with deep-space exploration since the early days of both. Since the discovery of turbo codes in 1993, the research community has invested a great deal of work on modern iteratively decoded codes, and naturally NASA's Jet Propulsion Laboratory (JPL) has been very much involved. This paper describes the research, design, implementation, and standardization work that has taken place at JPL for both turbo and low-density parity-check (LDPC) codes. Turbo code development proceeded from theoretical analyses of polynomial selection, weight distributions imposed by interleaver designs, decoder error floors, and iterative decoding thresholds. A family of turbo codes was standardized and implemented and is currently in use by several spacecraft. JPL's LDPC codes are built from protographs and circulants, selected by analyses of decoding thresholds and methods to avoid loops in the code graph. LDPC encoders and decoders have been implemented in hardware for planned spacecraft, and standardization is under way.

关键词： bounds Consultative Committee for Space Data Systems (CCSDS) error-correction coding low-density parity-check (LDPC) code protograph spacecraft space vehicle communication turbo code

来源：评论

学校读者我要写书评

暂无评论

Determination of error values for algebraic-geometry codes and the Forney formula

引用

IEEE TRANSACTIONS ON INFORMATION THEORY 1998年第5期44卷 1881-1886页

作者： Hansen, JP Jensen, HE Kotter, R Aarhus Univ Dept Math DK-8000 Aarhus C Denmark Tech Univ Denmark Dept Math DK-2800 Lyngby Denmark IBM Corp Res Lab San Jose CA USA

In the decoding of one-point algebraic-geometry codes with one defining equation in two variables we generalize the Forney formula for the Bose-Chaudhuri-Hocqungham (BCH) codes.

关键词： algebraic-geometric codes BCH codes decoding error-correction coding Forney formula

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：