Soonhee Kwon

Single device data correction (SDDC) is a main reliability, availability, and serviceability feature of DRAM systems in servers due to the significant hard-failure rate associated with DRAM devices. To correct errors in one DRAM device, error pattern is determined by even parity bits and error location is determined by the error pattern and cyclic redundancy check (CRC) bits in SDDC decoding. In this brief, a SDDC decoding scheme is proposed, which improves the error-correction performance by uniquely determining the error location. For that purpose, requirements for binary CRC generator polynomials to uniquely determine the error location are derived. Based on these requirements, a systematic method for constructing CRC generator polynomials is proposed, which guarantees 100% error-correction rate. Finally, it is confirmed that the proposed SDDC decoding scheme has lower decoding complexity compared with various ECC schemes and also shows 100% SDDC decoding success through simulation.

Error-correcting codes (ECCs) are essential to improve the reliability of digital communication systems. ECCs can detect or correct the errors by introducing and utilizing the systematic parity check bits, which however deteriorate the spectral efficiency of digital communication systems. In order to enhance the spectral efficiency, the used ECC may be blindly detected at the receiver. Also, blind detection of ECCs is important in the broadcasting systems. Recently, blind detection schemes of ECCs have been actively studied and most of them assume that the receiver knows which type of ECC, a block code or a non-block code, is used. However, in real situations, blind classification about whether the ECC is a block code or a non-block code should be performed first. In this paper, a blind classification scheme of ECCs in a noisy environment is proposed, which does not require the knowledge of parameters of the used ECC. The proposed scheme classifies whether the received bit-stream is encoded by an ECC or not, and if it is determined that the received bit-stream is encoded, the proposed scheme further classifies whether the used ECC is a block code or a non-block code. Also, a novel rank calculation scheme of the intercepted matrix is proposed by performing a probabilistic analysis of random row permutation for the intercepted matrix. Based on this analysis, the minimum number of random row permutations is theoretically derived for guaranteeing correct rank calculation with probability at least β. Through various simulations, it is shown that the proposed rank calculation and blind classification schemes outperform the existing rank calculation and blind classification schemes. Furthermore, it is verified that the performance gap between the proposed schemes and the existing schemes becomes larger as β is increased.

In this paper, the theoretical lower-bound on the success probability of blind reconstruction of Bose–Chaudhuri–Hocquenghem (BCH) codes is derived. In particular, the blind reconstruction method of BCH codes based on the consecutive roots of generator polynomials is mainly analyzed because this method shows the best blind reconstruction performance. In order to derive a performance lower-bound, the theoretical analysis of BCH codes on the aspects of blind reconstruction is performed. Furthermore, the analysis results can be applied not only to the binary BCH codes but also to the non-binary BCH codes including Reed–Solomon (RS) codes. By comparing the derived lower-bound with the simulation results, it is confirmed that the success probability of the blind reconstruction of BCH codes based on the consecutive roots of generator polynomials is well bounded by the proposed lower-bound.

In this paper, a new algorithm for blind reconstruction of generator polynomial for narrow-sense Bose-Chaudhuri-Hocquenghem (BCH) codes is proposed. The proposed algorithm uses the property that the number of valid codewords is differed with respect to the dimension of code. Furthermore, by following the channel cross-over probability of binary symmetric channel (BSC), the probability that a received codewords is the valid codewords of a BCH code is calculated and used in proposed algorithm. Through the hypothesis test which use the number of valid codewords, the BCH code used at the transmitter is distinguished at the receiver and then the generator polynomial can be reconstructed. Simulation results confirm that the proposed algorithm has much better recognition performance than the previous method.

In this letter, a blind reconstruction method of Bose-Chaudhuri-Hocquenghem (BCH) codes is proposed, which uses the property that all the codeword polynomials of a t-error correcting BCH code have the same 2t consecutive roots over Galois field. The proposed method inherently eliminates most of the erroneous codewords from the received codewords by utilizing the information about the starting position and length of consecutive roots of each received codeword. Therefore, the blind reconstruction performance is substantially improved and the simulation results confirm that the proposed method outperforms other blind reconstruction methods.