低系统开销的多TSV子阵列联合数据传输方法

串扰抑制编码往往具有图形限制特性,在小规模硅通孔(through silicon via,TSV)阵列中应用时,可以在合理的编解码器面积开销下取得良好的串扰抑制效果.为了在大规模的TSV阵列中实现低系统开销的高质量数据传输,提出基于多TSV子阵列联合数据传输的方法.针对参与数据联合传输的子阵列最优数量问题,通过研究子阵...     

片上网络的低功耗编码方法研究

从编码的角度出发,对降低片上网络的互连线功耗的方法进行了分析和研究.通过在片上微网络中采用纠错编码降低互连线电压摆幅的方法,在保证可靠性的同时,降低了功耗,实现了可靠性与功耗的合理折中.采用避免串扰码有效地减少线间耦合,从而达到降低线间耦合功耗的效果.并对纠错码与避免串扰码相结合降低互连线功耗的方法进行了分析.采用0.13μm CMOS工艺对各种编码方案进行了功耗仿真,结果显示:几种方案中联合编码方案节省功耗的效果最为明显.     

星载数据加密容错研究

在空间辐射环境中,单粒子反转效应(SEU)会导致星载系统存储器逻辑位发生翻转,且无法单纯依赖硬件措施完全消除,又由于卫星通信加密设备在大多数加密模式下具有错误扩散特性,星载数据加密设备的SEU软故障会导致批量数据不可用.针对星载数据加密过程的SEU影响问题,设计了基于奇偶校验码的星载数据加密过程检错算法和基于海明码的星载数据加密过程纠错算法,该容错方案可以有效降低SEU对星载数据加密过程的影响,提高星载数据加密的可靠性.通过大量图像数据仿真实验结果表明,提出的容错方案对星载数据加密过程可靠性的提高率与位出错概率成反比,有较好的空间适应性.     

Efficient dynamic priority based soft error mitigation techniques for configuration memory of FPGA hardware

Radiation-induced single bit upsets (SBUs) and multi-bit upsets (MBUs) are more prominent in Field Programmable Gate Arrays (FPGAs) due to the presence of a large number of latches in the configuration memory (CM) of FPGAs. At the same time, SBUs and MBUs in the CM can permanently or temporarily affect the hardware circuit implemented on FPGA. Hence, error mitigation and recovery techniques are necessary to protect the FPGA hardware from permanent faults arising due to such SBUs and MBUs. Different existing techniques used to mitigate the effect of soft errors in FPGA have high overhead and their implementations are also quite complex. In this paper, we have proposed efficient single bit as well as multi-bit error correcting methods to correct errors in the CM of FPGAs using simple parity equations and Erasure code. These codes are easy to implement, and the needed decoding circuits are also simple. Use of Dynamic Partial Reconfiguration (DPR) along with a simple hardware scheduling algorithm based download manager helps to perform the error correction in the CM without suspending the operations of the other hardware blocks. We propose a first of its kind methodology for novel transient fault correction using efficient error correcting codes with hardware scheduling for FPGAs. To validate the design we have tested the proposed methodology with Kintex FPGA. We have also measured different parameters like fault recovery time, power consumption, resource overhead and error correction efficiency to estimate the performance of our proposed methods.     

快速响应码的识别和解码

研究了快速响应码(QR Code)的识别方法和解码方法。在识别过程中采用Hough变换检测QR码的倾斜角度,通过几何计算纠正失真,并利用双线性插值算法将QR码旋转至水平,然后用Sobel边缘检测算子以及投影算法计算出QR码单元模块的边界。提供的方法能够快速、准确地识别出QR码,有效地抑制了拍摄QR码时产生的失真、噪声、倾斜等因素对QR码识读过程中的影响,提高了QR码的识别率。同时研究给出了QR码进行RS纠错译码过程中应注意的有关在有限域中的运算、如何求解伴随多项式、确定错误位置值和计算错误值的问题。     

A new efficient error control algorithm for wireless sensor networks in smart grid

Error detection and correction is an important issue in the design and maintenance of a smart grid communication network to provide reliable communication between sender and receiver. Various error-control coding techniques are employed to reduce bit error rates (BER) in wireless sensor networks (WSNs). The performance of these techniques is also compared and evaluated to find the most suitable technique for WSNs. This is the first study to compare the most efficient coding techniques in the smart grid environment, and it suggests a new error correction algorithm based on this comparison result. Therefore, this article first examines and compares two forward error control (FEC) coding techniques such as Bose-Chaudhuri-Hochquenghem code (BCH) and Reed Solomon code (RS) with various modulation methods including frequency shift keying (FSK), offset quadrature phase-shift keying (OQPSK), and differential phase shift keying (DPSK) in a 500 kV line-of-sight (LoS) substation smart grid environment. Second, as a result of this comparison, a new adaptive error control (AEC) algorithm is proposed. Adaptive error control adaptively changes error correction code (ECC) based on the channel behavior that is observed through the packet error rate (PER) in the recent previous transmissions. The link-quality-aware capacitated minimum hop spanning tree (LQ-CMST) algorithm and the multi-channel scheduling algorithm are used for data transmission over the log-normal channel. Therefore, the performance of compared coding techniques and AEC are also evaluated when multiple channels are used during transmission. Further, AEC is compared with static RS and without-FEC methods based on performance metrics such as the throughput, BER, and delay in different smart grid environments, e.g., 500 kV Substation (LoS), underground network transformer vaults (UTV) (LoS), and main power control room (MPR) (LoS). Our simulation results indicate that the proposed AEC algorithm achieves better performances than all those techniques.     

准可逆同步变长码

使码字能双向解码和构造同步字是当前提高变长码（VLC）自身容错能力的最主要两种方法,其中又分别以可逆变长码（RVLC）和同步变长码（SVLC）为主要代表。在SVLC中,找到了一类结合了这两种方法的VLC,它是移位对称数为2的整数次幂的SVLC。如果在用该码编码后的序列前中填加一同步字,则新序列可实现双向解码,故我们称之为准可逆同步变长码（QRSVLC）。QRSVLC的编码效率高于对称的RVLC,与非对称的RVLC相差无几。它还具有每个码字都包含同步字等优点。     

All unidirectional error-detecting code for universal applications

A code has been devised with a minimum distance D(c) = 2 to detect all unidirectional errors possible during communication. The ten decimal digits 0 to 9 are encoded using code words, each of which have seven bits. This is an unordered code with the minimum complexity in encoding and decoding to identify a codeword. The code is framed employing the uniform weight policy. This unique feature makes our code a complete unidirectional error-detecting code. In addition, the code proposed can correct one unidirectional error automatically by the proposed receiving-end logic. In addition, a uniform weighted code is suggested for ASCII which can detect all unidirectional errors with a limited 1-bit error correction ability     

基于内建自测的软错误与老化在线检测

负偏置温度不稳定性为主的老化会造成时序违规故障及软错误故障。为此,提出软错误与老化在线检测器(SEAOS)。在器件正常工作的情况下,在线检测上述2种故障。复用并发内建逻辑块观察器,使得硬件开销不超过30%。实验结果表明,在0.18 μm工艺尺寸下,与经典检测结构相比,SEAOS有较好的检测能力,且硬件开销较少。     

基于BST-PUF模型的轻量型认证与会话密钥交换协议

为解决现有PUF密钥交换协议存在的纠错机制复杂、辅助数据过大而导致的高开销问题,利用新提出的比特自检PUF电路（BST-PUF）设计了一种轻量型认证与密钥交换协议,在含有PUF的密码设备与服务器之间进行安全认证并建立共享会话密钥。协议能实现双向认证与可靠的密钥交换,抵抗篡改攻击、中间人攻击、DoS攻击、物理探测攻击与建模攻击等各种攻击技术。协议采用BST-PUF电路和鲁棒响应提取器来生成可靠的响应,取代传统PUF和纠错码组合,将可靠性标志F作为辅助数据用来恢复密钥,大幅降低纠错复杂性,减少辅助数据长度并提升PUF利用率。     

Reliable network-on-chip design for multi-core system-on-chip

Network-on-chip (NoC) architectures must deliver good latency-through put performance in the face of tight power and area budgets. However, in high-performance chip design, a significant design challenge is how to fulfill the requirements of circuit noise elimination, since the faults will slow down performance and dissipate much of the overall system power. This paper presents a simple coding scheme for reducing power dissipation, crosstalk noise, and crosstalk delay on the bus while simultaneously detecting errors at runtime. It uses a simple bus-invert encoding technique to reduce the prohibited transitions in terms of crosstalk noise and power dissipation. We also design a corresponding detector to detect errors at the input of the NoC routers. It can save energy by interrupting communications without storing and routing the packets when errors occur during transmissions. The experimental results for various multimedia applications show significant reduction in the number of patterns that are most likely to produce crosstalk errors. The results also show that it is attractive in terms of cost to apply the detecting logic to routers in the NoC with respect to the power consumption.     

基于戈莱码的真彩图像空域信息隐藏方法研究

（23,12）戈莱码真彩色图像空间域信息隐藏方法是一种以真彩色图像为载体,利用戈莱码编码冗余携带秘密信息的新的信息隐藏方法。对秘密信息进行映射编码形成错误图样,以真彩色图像块高位加扰信息为戈莱码的编码数据,将编码产生的校验数据有选择地嵌入真彩色图像块的低位数据中,然后根据错误图样修改个别处于低位的校验位,完成秘密信息的隐写。理论分析和实验结果表明,方法具有良好的隐蔽通信性能。     

Entanglement-assisted operator codeword stabilized quantum codes

In this paper, we introduce a unified framework to construct entanglement-assisted quantum error-correcting codes (QECCs), including additive and nonadditive codes, based on the codeword stabilized (CWS) framework on subsystems. The CWS framework is a scheme to construct QECCs, including both additive and nonadditive codes, and gives a method to construct a QECC from a classical error-correcting code in standard form. Entangled pairs of qubits (ebits) can be used to improve capacity of quantum error correction. In addition, it gives a method to overcome the dual-containing constraint. Operator quantum error correction (OQEC) gives a general framework to construct QECCs. We construct OQEC codes with ebits based on the CWS framework. This new scheme, entanglement-assisted operator codeword stabilized (EAOCWS) quantum codes, is the most general framework we know of to construct both additive and nonadditive codes from classical error-correcting codes. We describe the formalism of our scheme, demonstrate the construction with examples, and give several EAOCWS codes     

面向HPC互连网络的低延迟前向纠错编码研究与实现

当前主流高性能互连网络的端口速率已达到100~400 Gbps,其单通道速率已达到25~50 Gbps。在这种高速率的网络上传输数据,前向纠错编码是提高其可靠性的必要技术。以太网国际规范IEEE 802.3采用的前向纠错编码为RS(528,514)和RS(544,514),但是这2种码型难以满足高性能互连网络在低延迟方面的性能需求。首先,分析了RS的编码和译码结构,并定量研究了RS码型参数与编解码延迟之间的关系。接着,提出了一种面向当前高性能互连网络的新型低延迟编码—RS(271,257),并比较了该码型在占用带宽和纠错能力等方面的优缺点。最后,实现了基于RS(271,257)的低延迟网络编码子层,并对其进行了资源消耗评估和延迟性能模拟。综合考虑资源消耗、纠错能力和延迟性能3方面因素,RS(271,257)是一种理想的低延迟前向纠错码型,可满足当前面向HPC的低延迟高性能互连网络的编码子层的设计需求。     

一种检测与校正JPEG数据传输错误的新方法

无线传输JPEG数据时，由于信道存在噪音，经常会发生偶然性错误或突发性错误，因此错误检测与恢复在无线传输JPEG图像中有着举足轻重的作用。由于JPEG图像对传输错误非常敏感，一个bit位的传输错误就会影响后续位的解码，从而造成图像质量的严重下降。传统的处理JPEG传输错误是采用错误掩藏与编码自同步方法。其中错误隐藏是使用插值的方法来恢复数据，但其会在一定程度上降低传输图像的质量；编码自同步方法则会影响传输数据的通用性。为了更好地检测与校正JPEG数据传输错误，提出了一种新的JPEG编码数据传输错误检测与恢复方法。该方法以图像相关性作为判别依据，使用全搜索的方法来恢复数据。通过对该方法可行性进行的理论分析和仿真的实验表明，该方法可以更好地恢复偶然性传输错误，并可极大提高无线传输JPEG图像的质量。     

Design of the coarse-grained reconfigurable architecture DART with on-line error detection

This paper presents the implementation of the coarse-grained reconfigurable architecture (CGRA) DART with on-line error detection intended for increasing fault-tolerance. Most parts of the data paths and of the local memory of DART are protected using residue code modulo 3, whereas only the logic unit is protected using duplication with comparison. These low-cost hardware techniques would allow to tolerate temporary faults (including so called soft errors caused by radiation), provided that some technique based on re-execution of the last operation is used. Synthesis results obtained for a 90 nm CMOS technology have confirmed significant hardware and power consumption savings of the proposed approach over commonly used duplication with comparison. Introducing one extra pipeline stage in the self-checking version of the basic arithmetic blocks has allowed to significantly reduce the delay overhead compared to our previous design.     

Error-resilient pattern classification using a combination of spreading and coding gains

An approach that aims to enhance error resilience in pattern classification problems is proposed. The new approach combines the spread spectrum technique, specifically its selectivity and sensitivity, with error-correcting output codes (ECOC) for pattern classification. This approach combines both the coding gain of ECOC and the spreading gain of the spread spectrum technique to improve error resilience. ECOC is a well-established technique for general purpose pattern classification, which reduces the multi-class learning problem to an ensemble of two-class problems and uses special codewords to improve the error resilience of pattern classification. The direct sequence code division multiple access (DS-CDMA) technique is a spread spectrum technique that provides high user selectivity and high signal detection sensitivity, resulting in a reliable connection through a noisy radio communication channel shared by multiple users. Using DS-CDMA to spread the codeword, assigned to each pattern class by the ECOC technique, gives codes with coding properties that enable better correction of classification errors than ECOC alone. Results of performance assessment experiments show that the use of DS-CDMA alongside ECOC boosts error-resilience significantly, by yielding better classification accuracy than ECOC by itself.     

Energy reduction through crosstalk avoidance coding in networks on chip

Commercial designs are currently integrating from 10 to 100 embedded processors in a single system on chip (SoC) and the number is likely to increase significantly in the near future. With this ever increasing degree of integration, design of communication architectures for large, multi-core SoCs is a challenge. Traditional bus-based systems will no longer be able to meet the clock cycle requirements of these big SoCs. Instead, the communication requirements of these large multi processor SoCs (MP-SoCs) are convened by the emerging network-on-chip (NoC) paradigm. Crosstalk between adjacent wires is an important signal integrity issue in NoC communication fabrics and it can cause timing violations and extra energy dissipation. Crosstalk avoidance codes (CACs) can be used to improve the signal integrity by reducing the effective coupling capacitance, lowering the energy dissipation of wire segments. As NoCs are built on packet-switching, it is advantageous to modify data packets by including coded bits to protect against the negative effects of crosstalk. By incorporating crosstalk avoidance coding in NoC data streams and organizing the CAC-encoded data packets in an efficient manner, so that total number of encoding/decoding operations can be reduced over the communication channel, we are able to achieve lower communication energy, which in turn will help to decrease the overall energy dissipation.     

基于人工神经网络的NoC智能动态链路管理方法

功耗是片上网络(NoC)主要限制因素,链路状态的选择性开/关切换算法可降低电路级和系统级的链路功耗,这些算法大多集中于一个简单的静态阈值触发机制,该机制决定了是否应该打开或关闭链路;为解决上述触发机制存在诸多限制,提出了一种针对NoC的人工神经网络(ANN,artificial neutral network)作为动态链路功耗管理方法,该方法基于对系统状态的有监督在线学习,通过使用小型可扩展的神经网络来关闭和打开链路,从而提高预测能力;基于人工神经网络的模型利用了非常低的硬件资源,并且可以集成在大型网状和环面NoC中;通过对不同网络拓扑上各种综合流量模型的仿真结果表明,与静态阈值计算相比,该方法在较低的硬件支出下可以节省功耗;可为解决链路管理NoC中的功耗问题提供思路。     

宽带MIMO电力线系统有限反馈预编码方法*

多输入多输出(multiple input multiple output, MIMO)宽带电力线通信(power line communication, PLC)系统中由于电磁耦合存在共信道干扰,从而限制系统信道容量性能。针对该问题,提出一种基于量化反馈的预编码算法。首先利用两个相位角对预编码矩阵进行参数化,通过对相位角均匀量化形成预编码码本;其次采用弦距离准则从码本中选取最优码字。最后基于数据流的子载波映射信息,提出一种新的功率分配方案。仿真结果表明,该算法利用码本索引可有效降低反馈开销,同时结合新的功率分配方案可有效降低系统误码率、提升系统吞吐量。