Visible Light Communications

In this paper, a new spreading technique for intensity modulation direct detection fiber-optic code-division multiple-access (FO-CDMA) communication systems is proposed. This new spreading technique is based on generalized optical orthogonal codes (OOC) with large cardinality and minimal degradation in performance when compared with a more optimum system, namely, an optical CDMA system using OOC with autocorrelation and cross-correlation value bounded by one, i.e., OOC ( = 1). To obtain the performance of such systems, we use a recently introduced communication scheme, namely, frame time-hopping (FTH)-CDMA with random coding. It is discussed that systems with generalized OOC patterns and random time-hopping coding are close in structure and performance. Furthermore, the performance of such systems is near the performance of optical CDMA with optimum but low cardinality OOC ( = 1), which further renders the practicality of the proposed technique with very large cardinality. Two new receiver structures for FO-CDMA, namely, chip-level detector with optimum comparator threshold and correlation receiver with an electrical hard limiter, are also proposed. Performance analysis for a binary pulse position FTH-FO-CDMA network is considered for the correlation receiver, chip-level detector, correlation receiver with an optical hard limiter, optimum receiver, and the two newly proposed receiver structures. The results also show that a chip-level detector with optimum comparator threshold is superior to a chip-level detector for received low signal powers, and predict that the performance of the correlation receiver with an electrical hard limiter is superior to all other considered receiver structures, e.g., requiring one third of transmission power to achieve a desired bit error rate when compared with other receiver structures. Index Terms-Chip-level detector, frame time-hopping (FTH), optical code-division multiple access (CDMA), optical hard limiter, optical orthogonal codes (OOC). I. INTRODUCTION O PTICAL code-division multiple access (CDMA) schemes based on intensity modulation/direct detection (IM/DD) not only utilize the potential of fiber-optic capacity but also remain compatible with today's widely used IM/DD optical communications systems. Among the very early techniques that Paper approved by I. Andonovic, the Editor for Optical Networks and Devices of the IEEE Communications Society. Manuscript

VLC technology is one of the most promising technologies in the generations of communications, especially 5G after the significant development of optical semiconductors, specific laser diode, and the use of FBMC modulation in the system. DCO-FBMC modulation surpasses all the disadvantages of DCO-OFDM modulation techniques, as it is characterized by high speed and large bandwidth, but this technique consumes high energy when converting a real bipolar signal into a positive unipolar by adding DC bias. Besides the challenge of illumination distribution indoor typical room, where the drop of the illumination appears in the middle of the room, besides the power consumption. The Flip-FBMC technique was proposed to solve this challenge, which helps convert the bipolar signal into unipolar by separating the positive part from the negative part and converting it into positive and merging it using Multiplexer and then sending the signal. Besides this, the authors presented in this paper a new lighting model with 5 luminescent units, using LD instead of LED. The Flip-FBMC profile gave better energy savings and BER performance than DCO-FBMC, besides a lighting model that covers dark areas and gives high SNR for the blind area and give save power 13.14% from consumed power.

Multi-band carrierless amplitude and phase modulation and subcarrier multiplexing (SCM) are combined to produce a novel multi-users access scheme for visible light communications (VLC). To demonstrate this scheme, an experimental and realistic scenario is set-up by using a low-cost commercial office white light-emitting diode (LED) downlight. Furthermore, subcarrier spacings are added to reduce the inter-channel interferences and the parameters of the pulse shaping filters are optimized. The distance between the transmitter and the receiver is fixed at 2.15 m. After the optimization, the experiment setup achieves a spectral efficiency of 5.08 b/s/Hz after subcarrier spacing and with very light post-processing. A total of 20 users can be provided with the multi-users access scheme with a sum data rate of 162.5 Mb/s. The receiving attocell is measured at 4.56 m 2 . To the best of our knowledge, the resulting work presents the highest range, and one of the highest spectral efficiencies for a phosphorous white LED (ph-LED)-based VLC system, thanks to subcarrier spacing. With SCM, it is also the first ph-LED-based VLC multi-users system. INDEX TERMS Multi-band CAP, subcarrier multiplexing, multi-user access, visible light communication, white LED, subcarrier spacing, attocell.

Visible light communication (VLC) is a promising technology that can jointly be used to accomplish the typical lighting functionalities of the light-emitting diodes (LEDs) and data transmission, where light intensity can be modulated on a high rate that cannot be noticed by the human eye. In this paper, a VLC simulation framework to study the effect of LEDs’ distributions on different room dimensions is proposed by considering the performance metrics such as light intensity quality in accordance with the International Organization for Standardization (ISO) recommendation, and data transmission efficiency measured in terms of bit error rate (BER). To achieve the abovementioned performance metrics, a VLC communication system is designed that modulates the data, transmits it over the room utilizing the communication channel that is modeled using an accurate ray-tracing algorithm, and receives it by exploiting different receivers that are uniformly distributed in the room. Our work is d...

This paper presents the comprehensive design, analysis, and simulation of a novel optical Directly Modulated Direct Detection Orthogonal Frequency Division Multiplexing (DM-DD-OFDM) system for Optical Wireless Communication (OWC). The proposed system is designed to operate at 15 Gbps, employing high-order Quadrature Amplitude Modulation (QAM) formats, specifically 4-QAM, 16-QAM, and 32-QAM. A principal innovation of this DM-DD-OFDM-OWC architecture is its design as a cost-effective solution, characterized by a compact form factor, low power consumption, and simplified implementation. This is achieved notably through the elimination of an external optical modulator at the transmitter. System performance was rigorously evaluated through the analysis of key metrics, including constellation diagrams, energy per bit to noise power spectral density ratio (E b /N o), Q-factor, eye diagrams, transmitter pointing error angle, operational wavelength, Error Vector Magnitude (EVM), power budget, and Bit Error Rate (BER) across varying OWC transmission ranges. Simulation results demonstrate that the system achieves excellent performance, supporting transmission over 500 km for 4-QAM. The higher-order formats, 16-QAM and 32-QAM, maintain a satisfactory link quality up to 200 km at a BER of approximately 10-3. Furthermore, at wavelengths of 850 nm and 1550 nm, the system can transmit signals over distances of up to 1100 km and 850 km, respectively, while maintaining an EVM of approximately 40%. These findings position the proposed technology as a suitable candidate for application in inter-satellite optical wireless communication systems, particularly within Low Earth Orbit (LEO) constellations.

Visible Light Communication (VLC) has the potential to advance Intelligent Transportation Systems (ITS). This study explores the current advancements of VLC in ITS applications that may enhance traffic flow, road safety, and vehicular communication performance. The potential, benefits, and current research trends of VLC in ITS applications are discussed first. Then, the state-of-the-art VLC technologies including overall concept, IEEE communication protocols, hybrid VLC systems, and software-defined adaptive MIMO VLC systems, are discussed. We investigated different potential applications of VLC in ITS, such as signalized intersection and ramp metering control, collision warning and avoidance, vehicle localization and detection, and vehicle platooning using vehicle-vehicle (V2V), infrastructure-vehicle (I2V), and vehicle-everything (V2X) communications. Besides, VLC faces several challenges in ITS applications, and these concerns, e.g., environmental issues, communication range issues, standards and infrastructure integration issues, light conditions and integration issues are discussed. Finally, this paper discusses various advanced techniques to enhance VLC performance in ITS applications, such as machine learning-based channel estimation, adaptive beamforming, robust modulation schemes, and hybrid VLC integration. With this review, the authors aim to inform academics, engineers, and policymakers about the status and challenges of VLC in ITS. It is expected that, by applying VLC in ITS, mobility will be safer, more efficient, and sustainable.

Visible light communications are limited by the narrow bandwidth of their sources as the light-emitting diodes, which restricts the high data rates transmission. A potential technique such as multi-carrier modulation is considered promising for achieving a high-speed data rate and enhancing system performance. This paper proposes turbo coding with unipolar orthogonal frequency-division multiplexing (U-OFDM) for indoor environments. The system under U-OFDM considerations can reduce the inter-symbol interference caused by multiple paths and mitigate burst errors by adopting an iterative turbo decoding. The system performance is evaluated regarding the bit error rate (BER) for the range of the signal-to-noise ratio (SNR) under receiver field-of-view (FOV) restriction. The obtained results show that the performance system of the target BER (below the threshold limit of 3.8×10−3) has a power penalty of ~9 dB for modulation order of 64 for quadrature amplitude modulation scheme, FOV of 50...

Optical wireless communications (OWCs) refer to wireless communication technologies which utilize optical carriers in infrared, visible light, or ultraviolet bands of electromagnetic spectrum. For the sake of an OWC link design and performance evaluation, a comprehensive understanding and an accurate prediction of link behavior are indispensable. Therefore, accurate and efficient channel models are crucial for the OWC link design. This paper first provides a brief history of OWCs. It also considers OWC channel scenarios and their utilization trade-off in terms of optical carrier, range, mobility, and power efficiency. Furthermore, the main optical channel characteristics that affect the OWC link performance are investigated. A comprehensive overview of the most important OWCs channel measurement campaigns and channel models, primarily for wireless infrared communications and visible light communications, are presented. OWCs channel models are further compared in terms of computation speed, complexity, and accuracy. The survey considers indoor, outdoor, underground, and underwater communication environments. Finally, future research directions in OWCs channel measurements and models are addressed. Index Terms-Wireless infrared communications, visible light communications, optical wireless channel characteristics, optical wireless channel measurements, optical wireless channel models. I. INTRODUCTION R ADIO frequency (RF) wireless systems designers have been facing the continuously increasing demand for

At present, LAS ERS has gained one of the most powerful inventions in the world, and has applications in the fields ranging from information processing to telecommunications, medical, consumer electronics, law enforcement, military weapons systems and engineering. Therefore, the optical connectivity in free space includes the utilization of LED or infrared laser. The "Hybrid Asymmetrically Clipped Optical Orthogonal Frequency division Multiplexing" (HACO-OFDM) achieves a better spectral efficiency relative to an "Asymmetrically Clipped Optical OFDM" (ACO-OFDM) while retaining the advantages of the techniques used. The proposed HACO-OFDM has superimposed with the COLEA software which is the tool for the speech analysis thereby tests the given voice signal using Fourier Transform and Linear Predictive coding techniques. HACO-OFDM hasn't directly invoked the optical output hence Light Fidelity is used here to show the advancements in technology. In this paper, the proposed HACO-OFDM technique (Both S LM and Clipping methods) analysis the accurate information by reducing PAPR with respect to Bit Error Rate and S ignal to Noise Ratio compare to Existing ACO-OFDM (S PR) and thus results in low bit error rate of 10-7 in Communication thereby increases the efficiency of system.

In this paper, we consider an indoor visible light communication (VLC) system with multiple "white" light emitting diodes serving to form overlapping wireless communication cells. In order to maintain seamless connectivity to mobile users, a handover procedure should be implemented. In particular, practical conditions such as blockages due to obstacles inside the room environment and the mobility of users can affect direct VLC connectivity. The use of reconfigurable intelligent surfaces (RISs) in optical wireless systems allows to exploit non-direct connectivity links, thus providing efficient communication links. In this paper, we present a proactive handover mechanism that exploits the presence of a RIS, in order to redirect the communication links in case of blockages. The proposed approach has been implemented both in hard and soft modes and assessed in terms of achievable data rate and handover latency for a user walking in a given reference room at different user speeds and blockage conditions. Our presented results and comparisons with conventional handover methods (i.e., without RIS) are helpful in showing the superiority of the presented algorithm.

Exploration of advanced modulation formats and multiplexing techniques for next generation optical access networks are of interest as promising solutions for delivering multiple services to end-users. This thesis addresses this from two different angles: high dimensionality carrierless amplitudephase (CAP) and multiple-input multiple-output (MIMO) radio-over-fiber (RoF) systems. High dimensionality CAP modulation has been investigated in optical fiber systems. In this project we conducted the first experimental demonstration of 3 and 4 dimensional CAP with bit rates up to 10 Gb/s. These results indicate the potentiality of supporting multiple users with converged services. At the same time, orthogonal division multiple access (ODMA) systems for multiple possible dimensions of CAP modulation has been demonstrated for user and service allocation in wavelength division multiplexing (WDM) optical access network. 2 × 2 MIMO RoF employing orthogonal frequency division multiplexing (OFDM) with 5.6 GHz RoF signaling over all-vertical cavity surface emitting lasers (VCSEL) WDM passive optical networks (PONs). We have employed polarization division multiplexing (PDM) to further increase the capacity per wavelength of the femto-cell network. Bit rate up to 1.59 Gbps with fiber-wireless transmission over 1 m air distance is demonstrated. The results presented in this thesis demonstrate the feasibility of high dimensionality CAP in increasing the number of dimensions and their potentially to be utilized for multiple service allocation to different users. MIMO multiplexing techniques with OFDM provides the scalability in increasing spectral efficiency and bit rates for RoF systems. High dimensional CAP and MIMO multiplexing techniques are two promising solutions for supporting wired and hybrid wired-wireless access networks. i First of all, I would like to attribute my sincere gratitude to my supervisor and co-supervisor, Professor Idelfonso Tafur Monroy and Assistant Professor Jesper Bevensee Jensen for their encouragement, support and enthusiasm. They always spent time with me and guided me through the problems that I have encountered. It is a privilege to work with them. Thanks a lot from my heart. I am very grateful to the Ministry of Higher Education of Malaysia (MOHE) and University of Tun Hussein Onn Malaysia (UTHM) for providing me with a scholarship. I would not have completed a Ph.D without this financial assistance. My warmest thanks are extended to my closest friend Lei, Xu, Xiaodan, and Ying. We have spent time together in the lab doing the experiment with a very good team working spirit. My sincere thanks to Kamau and Xianbin for their practical assistance. I would also like to thank all my colleagues at Metro-Access group, Darko, JJ, Neil, Alexey, Thang, Valeria, Roberto, Robert, Silvia, Alexander, Bomin, Miguel, David and also my colleagues in DTU Fotonik. I must also thank Evarist my ex-officemate in building 343 DTU Fotonik for sharing all the good food recipes. I want to thank to all my Malaysian friends in Denmark for friendship through all these years. Many thanks for supporting each other, and I really hope this friendship will last forever. The last, and foremost, I would like to thank my parents, mother in law, my brothers, my husband, Shamsudin Bin Awang and my two handsome heroes: Muhammad Hazlam and Muhammad Hulaif. Thanks for their 'dua', love, patience, and encouragement. This made my Ph.D study possible and joyful at DTU Fotonik.

Orthogonal Frequency Division Multiplexing (OFDM) merupakan teknik transmisi data dengan pembawa multicarrier dalam sinyal yang saling tegak lurus. OFDM dapat membawa data berkapasitas tinggi. Radio over Fiber merupakan hybrid teknologi yang menggabungkan teknologi sert optik dan gelombang radio.Dithering merupakan sebuah proses injeksi ke sinyal periodik untuk sistem linier dan nonlinier untuk mendapatkan tujuan yang digunakan untuk menambah karakteristik linier dari sistem open/close. Penelitian ini bertujuan untuk menganalisis unjuk kerja OFDM-RoF dengan menggunakan dithering dengan teknik modulasi 4-QAM (Quadrature Amplitudo Modulation). Hasil simulasi menunjukan bahwa pengaruh besarnya daya pada CW (Continous Wave) Laser, pengaruh dari panjang fiber dan mempengaruhi spectrum sinyal, konstelasi sinyal, dan daya terima pada receiver secara signifikan. Secara analisis sistem yang telah disimulasikan memberikan hasil bahwa variasi daya masukan pada CW Laser dengan daya 8 memberikan...

Visible Light Communication (VLC) adalah sebuah sistem komunikasi yang memanfaatkan cahaya tampak sebagai media dalam komunikasi antar perangkat. Pada penelitian ini, teknologi Visible Light Communication (VLC) dalam sistem komunikasi yang akan diimplementasikan ini informasi yang akan dikirim berupa video. Metodologi penelitian yang digunakan dengan cara mentransformasikan Informasi digital menjadi sinyal analog oleh modulator, kemudian diubah menjadi cahaya oleh lampu sehingga cahaya lampu mengandung informasi. Selanjutnya cahaya tersebut diterima oleh photodiode yang akan mengubah menjadi sinyal listrik. Sinyal listrik yang berupa sinyal analog tersebut diubah kembali menjadi informasi digital kembali oleh demodulator setelah sebelumnya dikuatkan terlebih dahulu. Dengan adanya penelitian ini, manusia dapat berkomunikasi atau bertukar informasi hanya dengan cahaya lampu. LED dapat mengirimkan sebuah informasi berupa video (gambar bergerak) yang akan diterjemahkan kembali oleh photodiode. Pada penelitian ini hasil gambar video yang tampak pada monitor yang dikirim melalui transmitter dengan menggunakan LED belum sempurna, hal ini disebabkan oleh faktor pemilihan LED dan photodiode yang belum sesuai untuk mengirimkan data sepenuhnya. Gain pada sistem transceiver memiliki rata-rata sebesar 7,78 dB. Dengan rata-rata faktor delay pembacaan frekuensi sebesar 17,49 µs.

Radio Microwave Digital berfungsi sebagai media pentransmisisan data wireless jarak jauh, dan terdiri dari 2 buah perangkat yaitu indoor unit dan outdoor unit. Untuk transmisi data yang baik maka diperlukan pula perangkat yang memenuhi standar, maka dari itu sangatlah penting dilakukan pengujian kehandalan suatu perangkat sebelum tersebut digunakan luas. Kehandalan suatu radio tidak terlepas dari sistem transport yang digunakannya dengan menggunakan metoda simulasi menjalankan suatu radio point to point. Berdasarkan parameter uji yang telah ditetapkan oleh PT.TELKOM selaku pemegang regulasi nasional dianalisis 3 sistem transport yang didukung yaitu PDH E-1, SDH STM-1 Optical, dan Ethernet. Dengan hasil pengujian bitrate PDH E-1 sebesar 2048 kbit/s ± 0 ppm. Daya yang dipancarkan STM-1 sebesar -7,00 dBm dengan nilai receive -30,75 dBm dan lebar gelombang sebesar 6,386 nm serta ketahanan terhadap jitter yang baik. Digunaan ethernet dengan pemanfaatan bandwidth sebesar 100% dan latency lebih kecil dari 10 ns. Dengan demikian, perangkat radio microwave ini layak digunakan.

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Visible light communication VLC is deemed as futuristic technology applied for both illumination and data communication due to the low-cost energy consumption, long life expectancy, huge bandwidth, and high security compared to radio frequency RF. Uncovered area, minimum signal-to-noise ratio (SNR) and received power results from the non-uniform distribution of small base stations (i.e. Optical attocells) in the room. In this paper, the researchers propose a new LEDs distribution of five optical attocells configuration model in order to optimize the received power distribution and SNR at the center of the room for indoor VLC system. The optical attocells configuration in terms of received power to fill the uncovered area at the center of the room has been investigated. The simulation results showed that the proposed attocells configuration saved 24.9% of the transmitted power. Besides that, the whole room was covered uniformly.  As a result, the received power and SNR are improved.

Subband index carrierless amplitude and phase modulation (SI-CAP) is proposed and investigated in this work to improve the performance of multi-band CAP (m-CAP). The bit-error-rate (BER) analysis of the proposed SI-CAP is derived and verified through computer simulations. A detection scheme is also developed for SI-CAP which achieves maximum likelihood (ML) performance at a significantly lower complexity. In addition, an experimental demonstration of the proposed SI-CAP is carried out for optical communication systems. Furthermore, adaptive equalization technique is implemented to further enhance the performance gain of SI-CAP. It is shown that for the same order of complexity, the SI-CAP exhibits higher spectral and energy efficiency in comparison to m-CAP. Therefore, the performance gain of SI-CAP along with its design flexibility make it a suitable candidate for optical communication systems. Index Terms-Multi-band carrierless amplitude and phase modulation (m-CAP), optical communication, visible light communication (VLC), index modulation (IM), step-index plastic optical fibre (SI-POF), adaptive equalization.

Visible light communications are limited by the narrow bandwidth of their sources as the light-emitting diodes, which restricts the high data rates transmission. A potential technique such as multi-carrier modulation is considered promising for achieving a high-speed data rate and enhancing system performance. This paper proposes turbo coding with unipolar orthogonal frequency-division multiplexing (U-OFDM) for indoor environments. The system under U-OFDM considerations can reduce the inter-symbol interference caused by multiple paths and mitigate burst errors by adopting an iterative turbo decoding. The system performance is evaluated regarding the bit error rate (BER) for the range of the signal-to-noise ratio (SNR) under receiver field-of-view (FOV) restriction. The obtained results show that the performance system of the target BER (below the threshold limit of 3.8×10−3) has a power penalty of ~9 dB for modulation order of 64 for quadrature amplitude modulation scheme, FOV of 50...

Abstrak Perkembangan teknologi informasi di era sekarang berkembang sangat pesat dikarenakan telah berubahnya seluruh informasi analog menjadi informasi digital, dan dengan berubahnya sistem analog ke sistem digital seluruh teknologi sangat memudahkan pengguna untuk mengaplikasikan teknologi tersebut karena sistem digital mempunyai banyak kelebihan dibandingankan sistem analog. Akan tetapi, dengan semakin canggihnya perubahan sistem informasi dan teknologi, akan ada kanal yang dilewati oleh sebuah sistem komunikasi. Kanal AWGN dan kanal Rayleigh adalah jenis kanal yang akan mempengaruhi proses modulasi yang ada. Selama ini belum ada simulator yang dapat memudahkan sistem pembelajaran pada mata kuliah sistem komunikasi sehingga menyebabkan kesulitan untuk dapat mempelajari banyak tentang ilmu yang ada di dalam sistem komunikasi terutama pada modulasi Quadrature Ampitude Modulation. Pada tugas akhir ini digunakan software matlab sebagai penunjang untuk melihat sebagaimana besar pengar...

Channel coding berfungsi untuk menjaga informasi atau data digital dari error yang mungkin terjadi selama proses transmisi dengan cara menambahkan bit redundansi (tambahan) ke dalam data yang akan dikirimkan. Pada penelitian ini, dilakukan simulasi dan analisa terhadap performansi teknik channel coding dan decoding menggunakan convolutional code dan algoritma viterbi pada kanal dengan AWGN (Additive White Gaussian Noise) menggunakan bahasa pemograman Matlab 7.1 serta menggunakan modulasi QPSK. Dalam simulasi diperoleh hasil perbandingan performansi antara sistem tanpa menggunakan channel coding dan decoding dengan sistem yang menggunakan teknik channel coding (convolutional code) dan decoding (algoritma viterbi). Hasil simulasi ditampilkan dalam bentuk grafik SNR (Signal to Noise Ratio) terhadap BER (Bit Error Rate). Standar BER yang digunakan adalah standar minimum untuk transmisi suara yaitu 10-3. Pada komunikasi tanpa covolutional code dan algoritma viterbi, sistem tidak dapat me...

Because of the efficiency of the system and the fact that it successfully completed the tasks that were given to it under specific conditions, we are compelled to look for a way to measure these requirements according to the conditions and guidelines that were established by the people who make use of the system. Conduct an investigation into the many techniques that are available for use in analysis in light of the following conditions: i) sufficient time to detect the mistake, ii) time to maintenance, iii) the total number of constituents involved in the analytical process, and iv) an explanation of the level of complexity provided to the user. In this article, we will provide a concise overview of a number of different approaches, along with our recommendations for the most effective ones based on the issues raised earlier.

Perkembangan teknologi telah menunjukkan peningkatan yang cukup signifikan, terutama untuk bidang komunikasi. Ini terbukti dengan banyaknya media komunikasi baik itu nirkabel maupun kabel. Pada penelitian ini digunakan cahaya sebagai media sistem komunikasi, selain fungsi cahaya sebagai penerangan. Pada penelitian ini direalisasikan prototype sistem komunikasi Laser yang memanfaatkan fungsi cahaya dari Laser untuk menjadi sistem komunikasi. Prototype sistem komunikasi laser ini terdiri dari pemancar dan penerima. Pemancar terdiri dari Laser, transformator audio dan batere. Sedangkan penerima terdiri dari photodioda, amplifier dan catu daya. Metode yang digunakan dalam pengukuran adalah metode Line of Sight (LOS) pada saluran terbuka dan saluran tertutup. Parameter yang dapat mempengaruhi hasil output sistem komunikasi adalah jarak dan cahaya luar, karena semakin jauh jarak tempuh Laser maka semakin kecil intensitas cahaya yang diterima receiver. Hasil yang diperoleh dari pengukuran transmisi bahwa pada kondisi siang hari sistem komunikasi laser yang dirancang dapat bekerja pada jarak 5 meter sedangkan pada malam hari bekerja pada jarak 10,5 meter.

Visible Light Communication (VLC) adalah sebuah sistem komunikasi yang memanfaatkan cahaya tampak sebagai media dalam komunikasi antar perangkat. Pada penelitian ini, teknologi Visible Light Communication (VLC) dalam sistem komunikasi yang akan diimplementasikan ini informasi yang akan dikirim berupa video. Metodologi penelitian yang digunakan dengan cara mentransformasikan Informasi digital menjadi sinyal analog oleh modulator, kemudian diubah menjadi cahaya oleh lampu sehingga cahaya lampu mengandung informasi. Selanjutnya cahaya tersebut diterima oleh photodiode yang akan mengubah menjadi sinyal listrik. Sinyal listrik yang berupa sinyal analog tersebut diubah kembali menjadi informasi digital kembali oleh demodulator setelah sebelumnya dikuatkan terlebih dahulu. Dengan adanya penelitian ini, manusia dapat berkomunikasi atau bertukar informasi hanya dengan cahaya lampu. LED dapat mengirimkan sebuah informasi berupa video (gambar bergerak) yang akan diterjemahkan kembali oleh photodiode. Pada penelitian ini hasil gambar video yang tampak pada monitor yang dikirim melalui transmitter dengan menggunakan LED belum sempurna, hal ini disebabkan oleh faktor pemilihan LED dan photodiode yang belum sesuai untuk mengirimkan data sepenuhnya. Gain pada sistem transceiver memiliki rata-rata sebesar 7,78 dB. Dengan rata-rata faktor delay pembacaan frekuensi sebesar 17,49 µs.

Despite years of development and deployment, the standardized IEEE802.11p communication for vehicular networks can be pushed toward insatiable performance demands for wireless network data access, with a remarkable increase of both latency and channel congestion levels when subjected to scenarios with a very high vehicle density. In some hard safety applications such as convoys, IEEE802.11p could seriously fail to meet the fundamental vehicular safety requirements. On the other hand, the advent of LED technologies has opened up the possibility of leveraging the more robust Visible Light Communication (VLC) technology to assist IEEE802.11p and provide seamless connectivity in dense vehicular scenarios. In this paper, we propose and validate a prediction-based vertical handover (PVHO) between VLC and IEEE802.11p meant to afford seamless switching and ensure the autonomous driving safety requirements. Algorithm validation and platoon system performance were evaluated using a specially implemented 802.11p-VLC module in the NS3 Network Simulator. The simulation results showed a speed-based dynamic redundancy before and after VLC interruptions with seamless switching. Moreover, the deployment of VLC for platoon intra-communication can achieve a 10-25% PDR gain in high-density vehicular scenarios.