A family of array codes with a maximum distance separable（MDS） property, named L codes, is proposed. The greatest strength of L codes is that the number of rows（columns） in a disk array does not be restricted by t...A family of array codes with a maximum distance separable（MDS） property, named L codes, is proposed. The greatest strength of L codes is that the number of rows（columns） in a disk array does not be restricted by the prime number, and more disks can be dynamically appended in a running storage system. L codes can tolerate at least two disk erasures and some sector loss simultaneously, and can tolerate multiple disk erasures（greater than or equal to three） under a certain condition. Because only XOR operations are needed in the process of encoding and decoding, L codes have very high computing efficiency which is roughly equivalent to X codes. Analysis shows that L codes are particularly suitable for large-scale storage systems.展开更多
We present an automatic repeat request（ARQ） free space optical（FSO） system, which consists of a pulse position modulation（PPM） hard decision and an ARQ. The new ARQ＇s data error detection is based on a PPM hard...We present an automatic repeat request（ARQ） free space optical（FSO） system, which consists of a pulse position modulation（PPM） hard decision and an ARQ. The new ARQ＇s data error detection is based on a PPM hard decision＇s results and can eliminate the traditional ARQ information redundancy. The results of the numerical simulation have a good agreement with theoretical analysis and show that the ARQ-FSO system can effectively improve the bit error rate（BER） performance of the direct hard decision PPM system. Additionally, the proposed system significantly improves the average throughput efficiency compared to traditional ARQ systems.These characteristics make the ARQ-FSO system suitable for application in low BER and complexity FSO scenarios.展开更多
Embedded RAM blocks（BRAMs） in field programmable gate arrays（FPGAs） are susceptible to single event effects（SEEs） induced by environmental factors such as cosmic rays, heavy ions, alpha particles and so on. As t...Embedded RAM blocks（BRAMs） in field programmable gate arrays（FPGAs） are susceptible to single event effects（SEEs） induced by environmental factors such as cosmic rays, heavy ions, alpha particles and so on. As technology scales, the issue will be more serious. In order to tackle this issue, two different error correcting codes（ECCs）, the shortened Hamming codes and shortened BCH codes, are investigated in this paper. The concrete design methods of the codes are presented. Also, the codes are both implemented in flash-based FPGAs. Finally, the synthesis report and simulation results are presented in the paper. Moreover, heavy-ion experiments are performed,and the experimental results indicate that the error cross-section of the device using the shortened Hamming codes can be reduced by two orders of magnitude compared with the device without mitigation, and no errors are discovered in the experiments for the device using the shortened BCH codes.展开更多
基金supported by the National Natural Science Foundation of China under Grant No.61202250
文摘A family of array codes with a maximum distance separable（MDS） property, named L codes, is proposed. The greatest strength of L codes is that the number of rows（columns） in a disk array does not be restricted by the prime number, and more disks can be dynamically appended in a running storage system. L codes can tolerate at least two disk erasures and some sector loss simultaneously, and can tolerate multiple disk erasures（greater than or equal to three） under a certain condition. Because only XOR operations are needed in the process of encoding and decoding, L codes have very high computing efficiency which is roughly equivalent to X codes. Analysis shows that L codes are particularly suitable for large-scale storage systems.
基金supported by the National Natural Science Foundation of China(No.61475049)the National Basic Research Program of China(No.2013CB29204)
文摘We present an automatic repeat request（ARQ） free space optical（FSO） system, which consists of a pulse position modulation（PPM） hard decision and an ARQ. The new ARQ＇s data error detection is based on a PPM hard decision＇s results and can eliminate the traditional ARQ information redundancy. The results of the numerical simulation have a good agreement with theoretical analysis and show that the ARQ-FSO system can effectively improve the bit error rate（BER） performance of the direct hard decision PPM system. Additionally, the proposed system significantly improves the average throughput efficiency compared to traditional ARQ systems.These characteristics make the ARQ-FSO system suitable for application in low BER and complexity FSO scenarios.
基金Supported by National Natural Science Foundation of China(11079045,11179003 and 11305233)
文摘Embedded RAM blocks（BRAMs） in field programmable gate arrays（FPGAs） are susceptible to single event effects（SEEs） induced by environmental factors such as cosmic rays, heavy ions, alpha particles and so on. As technology scales, the issue will be more serious. In order to tackle this issue, two different error correcting codes（ECCs）, the shortened Hamming codes and shortened BCH codes, are investigated in this paper. The concrete design methods of the codes are presented. Also, the codes are both implemented in flash-based FPGAs. Finally, the synthesis report and simulation results are presented in the paper. Moreover, heavy-ion experiments are performed,and the experimental results indicate that the error cross-section of the device using the shortened Hamming codes can be reduced by two orders of magnitude compared with the device without mitigation, and no errors are discovered in the experiments for the device using the shortened BCH codes.
