Erasure-Correction-Enhanced Iterative Decoding for LDPC-RS Product Codes

Low-density parity-check(LDPC)codes are widely used due to their significant errorcorrection capability and linear decoding complexity.However,it is not sufficient for LDPC codes to satisfy the ultra low bit error rate(BER)requirement of next-generation ultra-high-speed communications due to the error floor phenomenon.According to the residual error characteristics of LDPC codes,we consider using the high rate Reed-Solomon(RS)codes as the outer codes to construct LDPC-RS product codes to eliminate the error floor and propose the hybrid error-erasure-correction decoding algorithm for the outer code to exploit erasure-correction capability effectively.Furthermore,the overall performance of product codes is improved using iteration between outer and inner codes.Simulation results validate that BER of the product code with the proposed hybrid algorithm is lower than that of the product code with no erasure correction.Compared with other product codes using LDPC codes,the proposed LDPC-RS product code with the same code rate has much better performance and smaller rate loss attributed to the maximum distance separable(MDS)property and significant erasure-correction capability of RS codes.

MATRIX PRODUCT CODES WITH ROSENBLOOM-TSFASMAN METRIC

In this article, the Rosenbloom-Tsfasman metric of matrix product codes over finite commutative rings is studied and the lower bounds for the minimal Rosenbloom- Tsfasman distances of the matrix product codes axe obtained. The lower bounds of the dual codes of matrix product codes over finite commutative Frobenius rings are also given.

HIHO Decoding Algorithms of Turbo Product Codes for High Rate Optical Communications

This paper presents a new Hard-Input Hard-Output (HIHO) iterative decoding algorithm for Turbo Product Codes (TPC), and especially describes the BCH-TPC codes aiming to alleviate error propagation and lower error floor. This algorithm mainly emp hasizes a decision mechanism for bit-flips, which thoroughly evaluates four different aspects of the decoding process, properly weighs and combines their respective reliability measures, and then employs the combined measure to make a judgment with regard to whether any particular bit should be flipped or not. Simulations result in a very steep Bit Error Rate (BER) curve indicating that a high-level net coding gain can be expected with a reasonable complexity. The simplicity and effectiveness of this HIHO decoding algorithm makes it a p romising candidate for the application in future high-speed fiber optical communications.

HIGH-PERFORMANCE SIMPLE-ENCODING GENERATOR-BASED SYSTEMATIC IRREGULAR LDPC CODES AND RESULTED PRODUCT CODES

Low-Density Parity-Check (LDPC) code is one of the most exciting topics among the coding theory community.It is of great importance in both theory and practical communications over noisy channels.The most advantage of LDPC codes is their relatively lower decoding complexity compared with turbo codes,while the disadvantage is its higher encoding complexity.In this paper,a new ap- proach is first proposed to construct high performance irregular systematic LDPC codes based on sparse generator matrix,which can significantly reduce the encoding complexity under the same de- coding complexity as that of regular or irregular LDPC codes defined by traditional sparse parity-check matrix.Then,the proposed generator-based systematic irregular LDPC codes are adopted as con- stituent block codes in rows and columns to design a new kind of product codes family,which also can be interpreted as irregular LDPC codes characterized by graph and thus decoded iteratively.Finally, the performance of the generator-based LDPC codes and the resultant product codes is investigated over an Additive White Gaussian Noise (AWGN) and also compared with the conventional LDPC codes under the same conditions of decoding complexity and channel noise.

Design and Implementation of a Novel Algorithm for Iterative Decoding of Product Codes

A novel product code iterative decoding algorithm and its high speed implementation scheme are proposed in this paper. Based on partial combination of selected columns of check matrix, the reduced-complexity syndrome decoding method is proposed to decode sub-codes of product code and deliver soft output information. So iterative decoding of product codes is possible. The fast sorting algorithm and a look-up method are proposed for high speed implementation of this algorithm. Compared to the conventional weighing iterative algorithm, the proposed algorithm has lower complexity while offering better performance, which is demonstrated by simulations and implementation analysis. The implementation scheme and verilog HDL simulation show that it is feasible to achieve high speed decoding with the proposed algorithm.

Decoding algorithms for shortened-extended turbo product codes in WiMAX systems

The component codes of turbo product codes in WiMAX systems are extended Hamming codes and single parity check codes as well as their shortened forms, In this paper, three novel iterative decoding algorithms based on Chase, MAP algorithms and their combination are proposed for shortened-extended turbo product codes. The iterative decoding algorithm based on Chase algorithm is proposed to reduce the decoding complexity without any performance loss. An efficient MAP algorithm is then proposed to decode the component codes of shortened single parity check codes and shortened-extended Hamming codes. A comprehensive performance comparison of the proposed decoding schemes is conducted for three typical classes of turbo product codes in WiMAX OFDMA systems. The suitable decoding algorithms are recommended for different classes based on the simulation results.

Integrated management system of agro-fishery products based on QR-code

Recently,both the importance and awareness relating to food safety relating to agrochemicals,chemical fertilizers,the pollution of ecosystem and unwholesome foods are growing rapidly.For the same reason,the purchaser's curiosity increases to know about the production process which can be accomplished by production traceability system.The traceability system can store and superintend the specific attribute information about products regarding the productive centre,producer and production finish data.The products undergo various circulation processes and they are being managed by individually constructed traceability system.Thus,it is difficult for the producer and the consumer to guarantee the safety from transpirable issues about the falsification of production traceability because the traceability information can be re-produced by forging through various ways.So in this paper,we proposed a system for integrated management of agro-fishery products based on quick response code(QR-code)for forgery prevention which may help to solve these issues.The proposed system makes QR-code using production information provided by producer.And then it is provided to the distributor and the consumer through integrated service model using the QR-code.Therefore,this system make sure to provide the same production traceability about the products to the distributor and the consumer and always keeps both updated with the same information.

Self-dual Codes with Symplectic Inner Product

In this paper, we discuss a kind of Hermitian inner product - symplectic inner product, which is different from the original inner product - Euclidean inner product. According to the definition of symplectic inner product, the codes under the symplectic inner product have better properties than those under the general Hermitian inner product. Here we present the necessary and sufficient condition for judging whether a linear code C over Fp with a generator matrix in the standard form is a symplectic self-dual code. In addition, we give a method for constructing a new symplectic self-dual codes over Fp, which is simpler than others.

QR Code在农产品质量安全追溯系统中的应用

针对农产品质量安全追溯系统中的溯源信息编码问题,研究了QR Code编码技术和识读方法。首先,比较了RFID和QR Code的不同特点,明确了QR Code在农产品质量安全追溯系统中的应用优势;然后,以国家标准GB/T18284-2000为依据,研究了QR Code符号结构与编码流程,并给出一个以C#引用QR Code.NET组件编程实现QR Code编码的实例;以此为基础,探讨了应用QR Code进行农产品质量安全追溯的途径,提出了利用智能手机识读QR Code的方法。分析结果表明,在农产品质量安全追溯系统中应用QR Code技术具有明显的经济性、有效性和简易性。

基于农产品质量安全追溯的QR Code编码应用与实现

针对农产品质量安全追溯平台中重要的条码技术,比较了一维条码和QR Code二维条码的差异,分析了QR Code二维条码的编码方法。以农产品质量安全追溯码32108811422681000001002112006为例,给出了QR Code二维条码编码的Java EE实现,经过试点应用,证明方法是可行的。

QR Code二维码在布匹信息管理系统中的应用

为解决布匹生产过程中数据手工输入效率低、可靠性差,无法动态跟踪各工序布匹实际运作状态等问题,将QR Code(Quick Response Code,快速响应码)二维码应用于布匹落布、布匹发放、工序收发等各生产环节。分析Delphi平台的FastReport5.0控件中QR二维码技术的特点,对工艺参数进行二维码图像加密,实现了布匹使用过程中数据的保密性和高安全性。通过对布匹信息管理系统的功能需求分析,提出二维码技术应用的整体架构,同时定制数据采集设备,介绍不同品种布匹的发放算法,并验证其逻辑可行性,有效地提高了工作效率,可为企业打造智能化生产流水线提供参考。

基于UCode的CPC编码系统

UCode为物联网潜在的重要编码方法,而产品总分类(CPC)是作为经济活动与产品的分类标准。在分析UCode编码和产品总分类编码的基础上,根据编码标识的唯一性原则和字段信息处理的局部性原则,提出了一种基于字符产品总分类编码与UCode编码的映射方法,实现了UID体系中用UCode编码格式实现产品总分类编码的方案,极大拓展了物联网编码的应用范围。

Form Gene Clustering Method about Pan-Ethnic-Group Products Based on Emotional Semantic

The use of pan-ethnic-group products form knowledge primarily depends on a designer＇s subjective experience without user participation. The majority of studies primarily focus on the detection of the perceptual demands of consumers from the target product category. A pan-ethnic-group products form gene clustering method based on emotional semantic is constructed. Consumers＇ perceptual images of the pan-ethnic-group products are obtained by means of product form gene extraction and coding and computer aided product form clustering technology. A case of form gene clustering about the typical pan-ethnic-group products is investigated which indicates that the method is feasible. This paper opens up a new direction for the future development of product form design which improves the agility of product design process in the era of Industry 4.0.

Studies on GIS Based Tracing and Traceability of Safe Crop Product in China

The safety of safe crop products （SCP） is critical to maintain people＇s health and living standard. With the global efforts on the improvement of the traceability of food products, it is inevitable to establish corresponding traceability systems to monitor the safety of crop products in China. In this article, the supply chain pattern of SCP in China has been analyzed and its spatial characters have been described in detail. The study deals with on how to relate traceability technology with GIS, and on how to trace and retrace the safety of SCP using the function of excellent spatial representation, spatial locating, and spatial analysis provided in GIS, which has been discussed from several aspects, such as coding technique of traceability information, transferring technique of traceability information, spatialization of traceability information, and application integration of traceability system. A pilot study was carried out to present the basic functions of the system, which provided an efficient and credible way to trace and retrace the safety of SCP in a real supply chain. An innovative idea has been brought forward for how to establish an efficient, credible, applied traceability system of SCP.

基于QR-Code的个性化电子名片的产品研究与实践

针对现阶段各种社交软件信息的流通单一性以及纸质名片不利于保存、流通性差、信息更新不及时的问题,本文设计了基于QR-Code的个性化电子名片。个性化电子名片程序将用户个人信息进行录入后,通过二维码的方式对信息进行展出,可直接保存,进行紧急联系,在社交中更有效率集中信息,及时传递信息。

Photonics Improvement of the Time-Bandwidth Product for a Linearly Chirped Waveform

A photonics approach to generate a linearly chirped waveform with increased TBWP is proposed and investigated. The time bandwidth product (TBWP) of the linearly chirped waveform is improved based on optical microwave frequency multiplying combined with temporal synthesis. An integrated dual-polarization modulator and an optical filter are utilized to perform frequency doubling operation by generating an orthogonally polarized optical signal, which consists of an optical carrier in one polarization direction and a second-order chirped optical sideband in another. Then the orthogonally polarized optical signal puts into a polarization modulator (PolM) to perform phase coding process. By driving a Pseudorandom (PN) sequence to the PolM, the time duration of the generated bandwidth doubled linearly chirped waveform can be synthesized to arbitrary length. The approach is verified by simulation. A linearly chirped waveform with central frequency of 8.25 GHz, bandwidth of 500 MHz, time duration of 6.4 ns is used to generate a synthesized waveform with central frequency of 16.5 GHz, bandwidth of 1 GHz, time duration of 819.2 ns. The TBWP of the linearly chirped signal is improved from 3.2 to 819.2. The proposed method features arbitrary large TBWP, and it can be used in a radar system to improve its resolution.

Estimation of Two-Dimensional Correction Factors for Min-Sum Decoding of Regular LDPC Code

In this paper, two-dimensional (2-D) correction scheme is proposed to improve the performance of conventional Min-Sum (MS) decoding of regular low density parity check codes. The adopted algorithm to obtain the correction factors is simply based on estimating the mean square difference (MSD) between the transmitted codeword and the posteriori information of both bit and check node that produced at the MS decoder. Semi-practical tests using software-defined radio (SDR) and specific code simulations show that the proposed quasi-optimal algorithm provides a comparable error performance as Sum-Product (SP) decoding while requiring less complexity.

Serial Genetic Algorithm Decoder for Low Density Parity Check Codes

Genetic algorithms are successfully used for decoding some classes of error correcting codes, and offer very good performances for solving large optimization problems. This article proposes a new decoder based on Serial Genetic Algorithm Decoder (SGAD) for decoding Low Density Parity Check (LDPC) codes. The results show that the proposed algorithm gives large gains over sum-product decoder, which proves its efficiency.

广东省东莞市生猪及其产品质量安全信息化监管模式

为解决猪肉产品消费环节与生猪养殖环节信息脱钩的问题,东莞市以数字喷码技术为基础,探索建立了生猪及其产品质量安全信息化监管模式,打通了从生猪养殖到猪肉产品消费各环节的信息关联,实现了生猪屠宰及肉产品质量安全可追溯和全产业链智慧监管。经东莞市2个生猪屠宰场及4个农贸市场试点证实,该模式可行有效,既节省了屠宰加工企业经营成本,又提高了肉产品价值,同时也提高了监管机构监管效率,使动物检疫行为更加规范,动物疫病防控能力得到增强,保障了东莞市猪肉肉产品质量卫生安全。东莞市的全过程信息化监管模式为其他地区的生猪产品信息化监管提供了借鉴。

《药品标准管理办法》解读与思考

2023年7月,国家药品监督管理局发布《药品标准管理办法》(以下简称《办法》)。本文就《办法》的主要内容进行解读,分析其存在的不足为:《办法》现有条文中对药品标准代号和药品标准信息化建设目标未明确。建议国家药品监督管理部门及时向标准化主管部门申请药品标准代号“YB”字母的确权,并将药品标准代号、编号规则在下一轮《办法》修正时写入条文,同时明确药品标准信息化体系建设目标;按用户界面层、计算处理层、数据存储层的基本框架搭建国家药品标准数据共享平台,免费向社会公开数字化药品标准,提供查阅和下载服务。