فهرس المقالات LDPC codes

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  1 - 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 أکثر

  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. تفاصيل المقالة
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  2 - 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 أکثر

  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. تفاصيل المقالة
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  3 - روشي جديد براي طراحي كدهاي آزمون توازن كم‌چگالي در طول كوتاه
  مهرداد تاکی محمدباقر نظافتي
  در اين مقاله روشي جديد براي طراحي كدهاي آزمون توازن كم‌چگالي در طول كوتاه پيشنهاد مي‌شود. شبيه‌سازي‌ها نشان مي‌دهند كه كدهاي طراحي‌شده در مقايسه با كدهاي LDPC طول كوتاه كه تاكنون طراحي شده‌اند، از عملكرد بهتري برخوردارند. در ساخت كدهاي LDPC براي طول‌هاي كوتاه دو مسأله أکثر

  در اين مقاله روشي جديد براي طراحي كدهاي آزمون توازن كم‌چگالي در طول كوتاه پيشنهاد مي‌شود. شبيه‌سازي‌ها نشان مي‌دهند كه كدهاي طراحي‌شده در مقايسه با كدهاي LDPC طول كوتاه كه تاكنون طراحي شده‌اند، از عملكرد بهتري برخوردارند. در ساخت كدهاي LDPC براي طول‌هاي كوتاه دو مسأله حائز اهميت است؛ اول آنكه پيش‌بيني تحليلي از عملكرد كد با استفاده از روش تكامل چگالي ، به دليل مبتني‌بودن اين روش بر استفاده از بينهايت‌بودن طول كد، امكان‌پذير نيست. دوم اينكه با توجه به زيادبودن نسبي چگالي كد امكان بروز حلقه‌هاي كوتاه در گراف متناظر كد بسيار زياد است و از آنجايي كه وجود حلقه در گراف كد باعث افت شديد عملكرد مي‌شود، اتخاذ روشي براي جلوگيري از ايجاد حلقه از اهميت بالايي برخوردار است. در اين مقاله براي هر دو مشكل فوق پيشنهاداتي ارائه شده است. اول آنكه ساختار كد بگونه‌اي انتخاب مي‌شود كه تا حد امكان عملكرد كد به آنچه روش تحليلي پيش‌بيني مي‌كند نزديك باشد، دوم اينكه با بهبود روش Extended Bit Filling روشي جديد براي كنترل حلقه‌هاي گراف كد ارائه مي‌شود. تفاصيل المقالة