6 research outputs found

    Dynamic evolving neural fuzzy inference system equalization scheme in mode division multiplexer for optical fiber transmission

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    The performance of optical mode division multiplexer (MDM) is affected by inter-symbol interference (ISI), which arises from higher-order mode coupling and modal dispersion in multimode fiber (MMF). Existing equalization algorithms in MDM can mitigate linear channel impairments, but cannot tackle nonlinear channel impairments accurately. Therefore, mitigating the noise in the received signal of MDM in the presence of ISI to recover the transmitted signal is important issue. This paper aims at controlling the broadening of the signal from MDM and minimizing the undesirable noise among channels. A dynamic evolving neural fuzzy inference system (DENFIS) equalization scheme has been used to achieve this objective. Results illustrate that nonlinear DENFIS equalization scheme can improve the received distorted signal from an MDM with better accuracy than previous linear equalization schemes such as recursive‐least‐square (RLS) algorithm. Desirably, this effect allows faster data transmission rate in MDM. Additionally, the successful offline implementation of DENFIS equalization in MDM encourages future online implementation of DENFIS equalization in embedded optical systems

    Design & investigation of 10x10 gbit/s MDM over hybrid FSO link under different weather conditions and fiber to the home

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    In this paper, we design and investigate 10-channels of mode division multiplexer (MDM) over hybrid free-space optics (FSO) link in several weather conditions to achieve the maximum possible medium range and fiber to the home (FTTH) for high bandwidth access networks. System capacity can be effectively increased with the use of MDM over hybrid FSO-FTTH. In this study, a 10-channel MDM over FSO-FTTH system has been analyzed in different weather conditions that operate at 1550 nm wavelength. The simulated system has transmitted 100 Gbit/s up for a distance of 3200 meters FSO in superbly clear weather condition. It also transmitted 100 Gbit/s up for a distance of 650 meters FSO during heavy rain. The validation of this study is measures based on eye diagrams bit-error rates (BER) that have been analyzed

    Hybrid Dy-NFIS & RLS equalization for ZCC code in optical-CDMA over multi-mode optical fiber

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    For long haul coherent optical fiber communication systems, it is significant to precisely monitor the quality of transmission links and optical signals. The channel capacity beyond Shannon limit of Single-mode optical fiber (SMOF) is achieved with the help of Multi-mode optical fiber (MMOF), where the signal is multiplexed in different spatial modes. To increase single-mode transmission capacity and to avoid a foreseen “capacity crunch”, researchers have been motivated to employ MMOF as an alternative. Furthermore, different multiplexing techniques could be applied in MMOF to improve the communication system. One of these techniques is the Optical Code Division Multiple Access (Optical-CDMA), which simplifies and decentralizes network controls to improve spectral efficiency and information security increasing flexibility in bandwidth granularity. This technique also allows synchronous and simultaneous transmission medium to be shared by many users. However, during the propagation of the data over the MMOF based on Optical-CDMA, an inevitable encountered issue is pulse dispersion, nonlinearity and MAI due to mode coupling. Moreover, pulse dispersion, nonlinearity and MAI are significant aspects for the evaluation of the performance of high-speed MMOF communication systems based on Optical-CDMA. This work suggests a hybrid algorithm based on nonlinear algorithm (Dynamic evolving neural fuzzy inference (Dy-NFIS)) and linear algorithm (Recursive least squares (RLS)) equalization for ZCC code in Optical-CDMA over MMOF. Root mean squared error (RMSE), mean squared error (MSE) and Structural Similarity index (SSIM) are used to measure performance results

    Free-space optics mode-wavelength division multiplexing system using LG modes based on decision feedback equalization

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    A free-space optics mode-wavelength division multiplexing (MWDM) system using Laguerre-Gaussian (LG) modes is designed using decision feedback equalization for controlling mode coupling and combating inter symbol interference so as to increase channel diversity. In this paper, a data rate of 24 Gbps is achieved for a FSO MWDM channel of 2.6 km in length using feedback equalization. Simulation results show significant improvement in eye diagrams and bit-error rates before and after decision feedback equalization

    A Framework for Blockchain Based E-Voting System for Iraq

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    Election is a basic democratic tool that offers an official mechanism for the people to express their opinions in order to form a government by democratic means. Electronic voting has evolved into the most significant application of e-governance and e-democracy. Few countries have recently taken the opportunity to test and use electronic voting systems. Also, many countries expect that internet voting will become a reality during the next decade. In the conventional voting system, the electors authenticate themselves by displaying credentials; this move is open to the public and is validated by poll workers. During this authentication, they are manually checked before being eligible to vote. The standard system of voting is more costly and needs more human capital. Because of these factors, the whole world is heading toward the trend of e-voting. Electronic voting devices are supposed to be the answer to the shortages. A secure e-voting system must meet many criteria, including uniqueness, performance, fairness, stability, safety, authentication, and anonymity. Blockchain is a modern security solution, which is capable of securing e-voting system. Blockchain is distributed ledger. Each block contains only one transaction. Block chain provides security using cryptography and hashing. Blockchain provides a perfect infrastructure to provide secure e-voting netwms.ork. Blockchain along with smart contracts need hour to improvise an e-voting system. This paper presents a secure blockchain based framework for an e-electronic voting in Iraq

    A Systematic Literature Review of Blockchain Technology

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    The Blockchain technology moves data nodes and data streams from one informatics center to another based on the importance of Bitcoins, resulting in a dedicated, public, and secure network for interpretation and development of the ensuing information chain reaction. Blockchains are frequently formed by connecting interrelated patterns of information in order to conduct a secure transaction. Blockchain has the characteristics of decentralization, transparency, immutability, autonomy, open-source, anonymity, and consensus. Blockchains are being utilized in a variety of real-world applications, including business and economics, financial technology, and digital currencies. This article does a comprehensive review of the literature on blockchain technology. While searching for the keyword "blockchain" as a subject, we identified a total of 1882 entries in these databases. After removing the less common record kinds, the papers were reduced to 1246 articles, which were then used for further investigation
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