Wyniki wyszukiwania - BazTech

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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.

2

Design and performance evaluation of vehicular visible light communication system under different weather conditions and system parameters

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

Opto-Electronics Review

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2023

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Vol. 31, No. 2

art. no. e145580

EN

Vehicular visible light communication is an emerging technology that allows wireless communication between vehicles or between vehicles and infrastructure. In this paper, a vehicular visible light communication system is designed using a non-return to zero on-off keying modulation scheme under the effect of different weather conditions such as clear, haze, and fog. The first model is a light emitting diode-based system and the second is a laser diode-based system. For both models, the influence of system parameters such as beam divergence, transceiver aperture diameters, and receiver responsivity is studied. The impact of the use of the trans-impedance amplifier is also investigated for both models. It was concluded that in the presence of the amplifier, output power of the light emitting diode and laser diode model are increased by 98.46 μW and 0.4719 W, respectively. The performance of the two proposed models is evaluated through bit error rate, quality factor, eye diagram, and output power to have some insightful results about the quality of service for the two proposed models. Under a specific weather condition, the performance of the system would be critical and other techniques should be applied. The maximum achievable link distance for the laser-based and light-emitting diode-based systems is 190 m at a data rate of 25 Gbps and 80 m at a data rate of 60 kbps, respectively, under the same system parameters and weather conditions. The obtained results provide a full idea about the availability of constructing our proposed model in a practical environment, showing a higher performance of the laser diode-based model than that of the light emitting diode-based model.

3

Sustainable adoption of Connected Vehicles in the Brazilian landscape: policies, technical specifications and challenges

Nascimento Douglas Aguiar do, Iano Yuzo, Loschi Hermes José, Razmjooy Navid, Sroufe Robert, Oliveira Vlademir de Jesus Silva, Castro Diego Arturo Pajuelo, Montagner Matheus

Transactions on Environment and Electrical Engineering

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2019

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Vol. 3, No. 1

44--62

EN

This review addresses the intervehicular communication in Connected Vehicles (CV) by emphasizing V2V (vehicle-to-vehicle) and V2I (vehicle-to-infrastructure) communications in terms of evolution, current standards, state-of-the-art studies, embedded devices, simulation, trends, challenges, and relevant legislation. This review is based on studies conducted from 2009 to 2019, government reports about the sustainable deployment of these technologies and their adoption in the Brazilian automotive market. Moreover, WAVE (Wireless Access in Vehicular Environment) and DSRC (Dedicated Short-range Communication) standards, the performance analysis of communication parameters and intervehicular available at the market are also described. The current status of ITS (Intelligent Transportation System) development in Brazil was reviewed, as well as the research institutes and governmental actions focused on introducing the concept of connected vehicles into the society. The Brazilian outlook for technological adoption concerning CVs was also discussed. Moreover, challenges related to technical aspects, safety and environmental issues, and the standardization for vehicle communication are also described. Finally, this review highlights the challenges and proposals from available technologies devoted to the roads and vehicular infrastructure communication, their evolution and upcoming trends.

4

Vehicular communication: state-of-the-art and remaining challenges

Strom E.G.

Przegląd Telekomunikacyjny + Wiadomości Telekomunikacyjne

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2015

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nr 4

119--120

EN

Vehicular communication is an enabler of many important applications. In this extended abstract, we argue that the remaining challenges for the current state-of-the-art system for direct V2X communication, i.e., systems based on the physical (PHY) and medium access control (MAC) layers of IEEE 802.11, are mainly antenna systems and channel estimation, for the PHY layer, and improving the scaling of the 802.11 MAC.

PL

Systemy komunikacji bezprzewodowej instalowane w pojazdach oraz elementach infrastruktury drogowej umożliwiają realizację wielu innowacyjnych aplikacji z zakresu bezpieczeństwa ruchu drogowego. Przedstawiono stan obecny prac związanych z rozwojem współczesnych systemów bezpośredniej komunikacji pojazdowej (V2V V2I, V2X) wykorzystujących warstwę fizyczną (PHY) oraz warstwę dostępu do medium (MAC) standardu IEEE 802.11. Poddano dyskusji ograniczenia tych standardów i wskazano problemy projektowania systemów antenowych dla pojazdów, efektywnej estymacji kanału radiowego oraz skalowalności warstwy MAC jako główne wyzwania związane z dalszym rozwojem rozważanych systemów.