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Non-line of sight analysis for vehicular visible light communication system : impact of artificial light source and weather conditions

Tawfik Nagwan I., El-Mokadem Eslam Samy, Aly Moustafa H., El-Deeb Walid S.

Opto-Electronics Review

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2024

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Vol. 32, No. 2

art. no. e150180

EN

Visible light communication is seen as a crucial technology within optical wireless communication systems. The technology of vehicular visible light communication holds significant importance in the context of connected vehicles. This technology can serve as a supplementary solution to vehicular systems that are based on radio frequency. In this paper, the authors conduct an analysis of the performance of both line-of-sight and non-line-of-sight vehicle-to-vehicle visible light communication systems under the effect of artificial light source and weather conditions, including clear, hazy, and foggy weather. A practical vehicular laser diode, a street lamp, and an avalanche photodiode are used to design the proposed system model. Performance enhancement for the proposed system is achieved using an optical amplifier at the receiving end. An artificial light source of light-emitting diode Corn-type is used to represent an ambient artificial light source. Different metrics such as quality factor and bit error rate are used to assess the system performance of the non-line-of-sight-vehicular communication system. The proposed line-of-sight model achieves a data rate of 25 Gbps, supporting a distance of 80 m under clear sky and hazy atmospheric conditions. For foggy weather, an attainable link distance of 70 m is achieved. The achieved results emphasize the suitability of the suggested models for vehicular applications in real world environment.

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Execution Simulation Design of Fiber-to-the- home (FTTH) Device Ingress Networks Using GPON with FBG Based on OptiSystem

Shabaneh Arafat Abdallah, Melhem Masa Loai

International Journal of Electronics and Telecommunications

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2022

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Vol. 68. No. 4

783--791

EN

Consumers require high-speed data transmission for different activities, such as smartphone usage, live broadcasting of news, and video conferencing. Therefore, a reliable communication network is needed to provide this kind of service to users. Fiber to the home (FTTH) is an optical fiber architecture that uses fiber cables in the access network for direct and final connection to homes or offices of customers. Networks based on FTTH can offer high performance, speed, and quality. An optical fiber communication system based on FTTH device ingress network using gigabit passive optical networks (GPONs) with fiber Bragg grating (FBG) and optical amplifier is designed and analyzed in this study. The developed design based on the FTTH device and FBG shows a low bit error rate (BER) for downstream and upstream configurations with an optical fiber length of 20 km. Downstream and upstream configurations achieve a Q-factor of 89.5 and 181.3, respectively. Achievable sensitivity of the developed system is −28 dBm, while the received signal based on OptiSystem is −25.59 dBm. FTTH with FBG will play a major role in the future and provide effective solutions for a wide variety of applications in network communication systems and data transmission rates.

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Artificial intelligence-based modeling for the estimation of Q-Factor and elastic young’s modulus of sandstones deteriorated by a wetting-drying cyclic process

Rashid Hafiz Muhammad Awais, Ghazzali Muhammad, Waqas Umer, Malik Adnan Anwar, Abubakar Muhammad Zubair

Archives of Mining Sciences

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2021

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Vol. 66, no. 4

635--658

EN

In this study, a series of destructive and non-destructive tests were performed on sandstone samples subjected to wetting-drying cycles. A total of 25 Wet-Dry cycles were provided to investigate any significant change in the engineering properties of sandstones in terms of their porosity, permeability, water absorption, density, Q-factor, elastic modulus (E), and unconfined compressive strength (UCS). The overall reduction in the values of density, E, Q-factor, and UCS was noted as 3-4%, 42-71%, 34-62%, and 26-70% respectively. Whereas, the overall appreciation in the values of porosity, permeability, and water absorption was recorded as 24-50%, 31-64%, and 25-50% respectively. The bivariate analysis showed that the physical parameters had a strong relationship with one another and their Pearson’s correlation value (R) ranged from 0.87-0.99. In prediction modeling, Q-factor and E were regressed with the contemplated physical properties. The linear regression models did not provide satisfactory results due to their multicollinearity problem. Their VIF (variance inflation factor) value was found much greater than the threshold limit of 10. To overcome this problem, the cascade-forward neural network technique was used to develop significant prediction models. In the case of a neural network modeling, the goodness of fit between estimated and predicted values of the Q-factor (R2 = 0.86) and E (R2 = 0.91) was found much better than those calculated for the Q-factor (R2 = 0.30) and E (R2 = 0.36) in the regression analysis.

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Analysis of inter-satellite free-space optical link performance considering different system parameters

Kaur Sanmukh

Opto-Electronics Review

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2019

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Vol. 27, No. 1

10--13

EN

The welcome and adaptation of optical wireless technology by the modern era has brought forward the concept of an inter-satellite free-space optical communication system. In the present work, I study the combined effect of selection of different operating wavelengths and detector types along with the pointing errors at the transmitter and receiver side on the performance of an inter-satellite free-space optical link. The link performance has been optimized by measuring and analyzing the bit error rate and quality-factor of received signal under different scenarios. Performance of the inter-satellite link has also been investigated considering different modulation formats and data rates for LEO and MEO distances.

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10 Gbps optical line using EDFA for long distance lines

Ivaniga P., Ivaniga T.

Przegląd Elektrotechniczny

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2017

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R. 93, nr 3

193--196

EN

The aim of this article is to demonstrate change in the BER (Bit Error Rate) and Q-factor in long distance lines. Nowadays it is not possible to create fully optical communication systems without software tools to simulate real optical networks under the given circumstances. There have been two 10 Gbps optical line topologies created: one without EDFA (Erbium Doped Fibre Amplifier) of up to 115 km and another using EDFA on a long distance line up to 3200 km. The article shows the BER worsening with the distance increasing and also the need for the link amplifier.

PL

Celem niniejszego artykułu jest przedstawienie zmian w BER (Bit Error Rate) oraz współczynnika Q na dużych odległościach. Obecnie nie jest możliwe stworzenie w pełni optycznych systemów komunikacyjnych bez użycia narzędzi programowych do symulacji rzeczywistych sieci optycznych w danych okolicznościach. Utworzono dwie 10 Gbps optyczne topologie liniowe: jedna bez EDFA (Erb z domieszką włókien Amplifier) maksymalnie do 115 km, a druga z użyciem EDFA na duże odległości do 3200 km. W artykule przedstawiono BER pogarszającą się wraz z rosnącą odległością.