List of Articles LDPC Codes

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  1 - Reliability Analysis of the Sum-Product Decoding Algorithm for the PSK Modulation Scheme
  Hadi Khodaei Jooshin Mahdi Nangir
  10.29252/jist.8.31.167
  Iteratively decoding and reconstruction of encoded data has been considered in recent decades. Most of these iterative schemes are based on graphical codes. Messages are passed through space graphs to reach a reliable belief of the original data. This paper presents a p More

  Iteratively decoding and reconstruction of encoded data has been considered in recent decades. Most of these iterative schemes are based on graphical codes. Messages are passed through space graphs to reach a reliable belief of the original data. This paper presents a performance analysis of the Low-Density Parity-Check (LDPC) code design method which approach the capacity of the Additive White Gaussian Noise (AWGN) model for communication channels. We investigate the reliability of the system under Phase Shift Keying (PSK) modulation. We study the effects and advantages of variation in the codeword length, the rate of parity-check matrix of the LDPC codes, and the number of iterations in the Sum-Product Algorithm (SPA). By employing an LDPC encoder prior to the PSK modulation block and the SPA in the decoding part, the Bit Error Rate (BER) performance of the PSK modulation system can improve significantly. The BER performance improvement of a point-to-point communication system is measured in different cases. Our analysis is capable for applying any other iterative message-passing algorithm. The code design process of the communication systems and parameter selection of the encoding and decoding algorithms are accomplished by considering hardware limitations in a communication system. Our results help to design and select paramours efficiently. Manuscript profile
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  2 - Reliability Analysis of the Joint LDPC Decoding Algorithms over the Multiple Access Channels
  Mahdi Nangir
  10.52547/jist.9.36.33
  The joint Low Density Parity-Check (LDPC) decoding schemes iteratively decode the received data from multiple channels. Mostly, the available data in different channels are correlated and there is kind of dependency between the links or channels. In recent decades, the More

  The joint Low Density Parity-Check (LDPC) decoding schemes iteratively decode the received data from multiple channels. Mostly, the available data in different channels are correlated and there is kind of dependency between the links or channels. In recent decades, the graph-based codes have been considered for the communication network scenarios. The performance of these codes is close to the existing theoretical bounds and their complexity is not high which cause the possibility of real world implementation and exploitation. The Multiple Access Channel (MAC) scenario with multiple senders which aim to send correlated data to a single receiver is considered. An analysis on the reliability of the Bit Error Rate (BER) performance of the Joint Sum-Product (JSP) decoding algorithm is presented for a two-link case, which can be extended to higher number of links. The effect of parameter variations on the BER performance is studied. These parameters include: the total number of iterations, the codeword length, the total number of rounds, and the coding rate in the JSP algorithm. An optimal value of the parameters is selected during the design procedure of a communication network by considering its limitations and complexity criterion. The JSP algorithm is a reliable scheme for jointly decoding of noisy binary data from different origins. Manuscript profile
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  3 - Error Reconciliation based on Integer Linear Programming in Quantum Key Distribution
  zahra eskandari mohammad  rezaee
  10.52547/jist.9.36.51
  Quantum telecommunication has received a lot of attention today by providing unconditional security because of the inherent nature of quantum channels based on the no-cloning theorem. In this mode of communication, first, the key is sent through a quantum channel that i More

  Quantum telecommunication has received a lot of attention today by providing unconditional security because of the inherent nature of quantum channels based on the no-cloning theorem. In this mode of communication, first, the key is sent through a quantum channel that is resistant to eavesdropping, and then secure communication is established using the exchanged key. Due to the inevitability of noise, the received key needs to be distilled. One of the vital steps in key distillation is named key reconciliation which corrects the occurred errors in the key. Different solutions have been presented for this issue, with different efficiency and success rate. One of the most notable works is LDPC decoding which has higher efficiency compared to the others, but unfortunately, this method does not work well in the codes with a high rate. In this paper, we present an approach to correct the errors in the high rate LDPC code-based reconciliation algorithm. The proposed algorithm utilizes Integer Linear Programming to model the error correction problem to an optimization problem and solve it. Testing the proposed approach through simulation, we show it has high efficiency in high rate LDPC codes as well as a higher success rate compared with the LDPC decoding method - belief propagation – in a reasonable time. Manuscript profile
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  4 - A New Approximate Analytical Method for Performance Analysis of Regular LDPC Codes Iterative Decoding on AWGN Channels
  H. Samimi P. Azmi Mohammad hakak
  In this paper we propose a new Gaussian-based analytical method for performance analysis of regular LDPC codes iterative decoding on AWGN channel. The proposed method has good accuracy and low complexity in comparison with current methods. Based on our developed analyti More

  In this paper we propose a new Gaussian-based analytical method for performance analysis of regular LDPC codes iterative decoding on AWGN channel. The proposed method has good accuracy and low complexity in comparison with current methods. Based on our developed analytical equations, we present an error propagation model for the iterative decoder of LDPC codes which can be used as a simple tool for convergence analysis of LDPC codes on the AWGN channel. Manuscript profile
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  5 - A New Method for Short Block Length LDPC Code Design
  M. Taki M. B. Nezafati
  In this paper, we propose a new method for short block length Low Density Parity Check (LDPC) code design. The experimental results show that codes designed using the proposed algorithm have better performance compare to the other short block length LDPC codes. For LDPC More

  In this paper, we propose a new method for short block length Low Density Parity Check (LDPC) code design. The experimental results show that codes designed using the proposed algorithm have better performance compare to the other short block length LDPC codes. For LDPC code design in short block length, two problems arise: first analytical estimation of code performance using density evolution method is unusable because of infinity of code length in this method. Second because of high code density, the probability of short loop in code graph (Girth) is high that dramatically reduces the code performance. We propose solution for both problems. First, code structure is designed in such a way that the code performance is near to that of the density evolution method estimates and second by improving Extended Bit Filling algorithm, short block length is controlled. Manuscript profile