Abstract This paper analyses the performance of a single-channel radio-over-fiber (RoF) communication system operating at a carrier frequency of 10 GHz at different data rates of 5 Gb/s, 10 Gb/s, and 20 Gb/s. The system is initially evaluated over link distance of 20 km (baseline) and then subsequently analyzed for extended transmission distances from 20 km to 50 km. It is observed that beyond 20 km, the system performance degrades severely, with complete signal failure occurring at intermediate link length of 30–40 kms, indicating a Q-factor of zero and BER equal to one. Partial recovery in the system performance is observed at 50 km, indicating the presence of dispersion-induced RF power fading. To diminish the effect of these impairments, dispersion-compensating fiber (DCF) is introduced for longer spans, which results in significant improvement in system performance. Additionally, the effect of laser launch power is evaluated over a range of −10 dBm to 15 dBm. The results indicate that the system operates in a power-tolerant regime up to 10 dBm, beyond which nonlinear effects degrade performance. The proposed system limitations are primarily governed by dispersion-induced fading rather than optical power and represent the effectiveness of dispersion compensation in improving RoF link performance.

For achieving higher data rates with better signal quality, free space optical communication is considered to be emerging wireless technology. However due to propagation losses and attenuation, the performance is highly impacted. So, the proposed work evaluates a dual-EDFA-assisted FSO system which operates at 10Gbps by using an EDFA at transmitter and a pre-amplifier is also used at receiver for compensating the attenuation. The performance is then analyzed in the form of BER, Q-factor and received optical power for various distances, EDFA gain, atmospheric attenuation and launch power with optisystem simulations. The obtained results indicate improved signal quality with dual stage amplification configuration. At an attenuation of 1dB/km and transmission distance of 3Km, 4Km, 5 km, Q factors of 15.7,10.8 and 6.1 respectively are achieved. The results prove acceptable performance upto 5 km for the considered assumptions. The proposed study additionally examines the amplifier gain influence with launch power impact on system performance.

Abstract This paper investigates the system performance in a hybrid SMF-FSO communication system that employs the 193.1 THz CW laser, Mach–Zehnder modulator, erbium-doped fiber amplifier (EDFA), and PIN photodiode. The proposed setup consists of 60 km single mode fiber (SMF), which is followed by a 1 km FSO link under varying atmospheric attenuation conditions ranging from 0.3 dB/km to 20 dB/km. To mitigate the chromatic dispersion in the fiber, the dispersion-compensating fiber (DCF) is integrated with partial and full compensation conditions. Furthermore, the placement of EDFA with preamplification and postamplification schemes is also analyzed. The system performance is investigated in terms of bit error rate (BER), received power, Q-factor, and the characteristics of eye diagrams. The simulation results indicate that incorporating DCF improves the quality of the signal under varying atmospheric attenuations, i.e., low and moderate attenuation conditions. The optimized amplifier placement increases the receiver sensitivity, which enhances the system reliability even under adverse weather conditions.

Abstract To fulfil the need for higher capacity and multi-user networks, Radio-over-Fiber (RoF) technology is a promising solution for obtaining higher bandwidth and efficiency over an optical fiber-based infrastructure network. RoF, when integrated with WDM, can support higher bandwidth and also provide flexibility in optical wireless networks. In the proposed work, a four-channel WDM-RoF-enabled technology is discussed and simulated. The proposed system operates at a rate of 2.5 Gbps and with a carrier centered at a frequency of 193.1 THz, 193.2 THz, 193.3 THz, and 193.4 THz. The signal after multiplexing is transmitted at 20 Kms with using a single-mode optical fiber and then amplified with a 10 dB EDFA to compensate for the losses, which at the receiver side is recovered using the process of demultiplexing, photodetection, and signal regeneration. The performance is analyzed with the metrics in the form of BER and Q-factor. The results of multi-user data transmission over an optical wireless integrated infrastructure which provides an acceptable signal for communication. The proposed system provides an efficient and flexible solution for 5G networks.

The increasing demand for high-speed and energy-efficient optical access networks requires adaptive solutions for varying traffic conditions. Conventional passive optical networks (PONs) employ a fixed power transmitter at the optical network unit (ONU), resulting in inefficient power utilization under varying load conditions. This paper proposes an energy-efficient scheme based on Access load difference between ONUs with Dynamic Wavelength Switching (ALD-DWS). In this scheme, a multi-level transmitter architecture is proposed that dynamically activates sub-transmitters based on real-time traffic demand. The proposed approach reduces energy consumption while maintaining acceptable system performance. The system is modeled and evaluated using OptiSystem simulations under different traffic loads. Performance of the system is analyzed in terms of bit error rate (BER), Q-factor, and received optical power. The results demonstrate that the proposed scheme achieves improved energy efficiency with negligible effect on signal quality as compared to fixed power conventional systems. The adaptive mechanism ensures scalable and reliable performance, making it suitable for next-generation optical access networks. The proposed technique, i.e., ALD-DWS, is based on a multi-level design for the transmitter at each ONU, where the sub-transmitters are enabled as per the load offered. Load difference at ONU is checked, and according to that, DWS will switch “ON” the required module such that if the data rate is less than 5 Gbps, then only the sub-transmitter, such as 2 Gbps×2, is switched “ON”. So, the results proposed shows 69

This research paper thoroughly studies modeling, simulation, and performance analysis of underwater optical fiber communication systems, with specific emphasis on submarine cable systems, which form the infrastructural backbone of the internet in the modern world. The study comprehensively covers the multilayered nature of deep-sea optical fiber cables and the engineering practices utilized to protect such systems from the dynamic and extreme nature of the seafloor. To simulate the performance of such complex systems, the paper utilizes OptiSystem, a high-end photonic and fiber-optic communication system design simulation software. Simulations are designed to mimic the nature of deployment in deep waters, testing important parameters like Bit Error Rate (BER), optical power loss, signal-to-noise ratio (SNR), and pulse broadening due to dispersion. The study simulates various scenarios, such as uncompensated and amplified transmission, to mimic real-world degrading and recovery processes. Emphasis is particularly given to signal integrity over distance, i.e., how loss and dispersion are prevented using Erbium-Doped Fiber Amplifiers (EDFAs), Raman amplifiers, and Dispersion Compensation Modules (DCMs). Their locations, spacings, and gains are determined for best quality transmission and economic viability. Wavelength Division Multiplexing (WDM) is also investigated as a technique for bandwidth multiplication with little interference and crosstalk.

Passive Optical Networks (PON) has revolutionized how users access network solutions. This revolution has provided advantages in various aspects. This includes cheap deployment, high-speed internet connectivity, scalability, and reduced power consumption. One major drawback that any optical system suffers from is attenuation. Attenuation causes signal power to drop significantly through an optical fiber network. This generates a need to use amplifiers to increase the signal power with low noise. At this given stage of technology, we have mainly two types of Optical Amplifiers, and they are Semiconductor Optical Amplifiers (SOA) and Erbium-Doped Fiber Amplifiers (EDFA). This article deals with the usage of these two amplifiers in a fixed ring topology model simultaneously with various iterations of optical length, position of amplifiers, baud rate, and Q-Factor at the receiver end. A brief comparison and a study have been made at the receiver and the sender end, to compare the signal efficiency for various iterations to determine the best combination for the ideal output. These Simulations have been carried out in Opti System and the values obtained have been plotted in MATLAB for better clarity and understanding.

Abstract Passive optical network (PON) has become the leader in delivering broadband high-speed connectivity. The paper introduces a detailed description of PON, its working principle, key features, and their potential applications. In addition, we discuss the types of PON architectures including GPON, EPON, and XG-PON with merits and demerits. Finally, we discuss the technical considerations of PONs in data transmission mechanisms, network design, and component selection. This paper further demonstrates the use of PON technology via a case study on the design and implementation of a bidirectional optical fiber network. Within this project, we went ahead to demonstrate the use of PON components including optical splitters, transmitters, receivers, and power controllers towards the development of an efficient and functional network structure. It mainly covered the results of the project since the PONs appeared to be a promising solution for obtaining high-performing and reliable broadband services.

Wavelength division multiplexing (WDM) is a modern technology used in optical fiber communication. It works on multiple data signals with different wavelengths to travel together in one fiber. The paper shows the design and simulation of a WDM system using Opti System software. Our goal is to check how well the system performs by looking at important factors like bit error rate (BER), optical signal-to-noise ratio (OSNR), and Q -factor. The system includes laser sources, modulators, WDM multiplexers, optical fiber, amplifiers (EDFA), and demultiplexers to send and receive multiple signals at once. We will study things like channel spacing, fiber loss, and noise affect the signal quality of a system. Opti system tools like spectrum analyzers, eye diagrams, and BER graphs were used to check the system’s performance. The optical spectrum shows various channels working together in the C-band. BER and Q -factor results show that the received signal is above threshold but can be better with some improvements. The system works well up to 50 km using amplifiers. This project shows that WDM over multiple channels is a good way to send fast and clear data over long distances using optical fiber.

High data rates applications are the current demand of data communication networks which uses optical fibers as a backbone network. This demand has raised the power consumption of optical network units in passive optical networks (PONs). So cyclic sleep techniques in PONs can save the energy consumption during idle slots and low traffic conditions. In the proposed paper cyclic sleep is implemented at the ONU with the help of a single-drive MZM placed after Gaussian filter in every channel because of less energy feature and high bandwidth objective. MZM is being driven by a low-frequency NRZ/PRBS control signal. The results shown in this paper well represents less power consumption using cyclic sleep which results in more energy efficiency to improve the power savings. In the proposed paper cyclic sleep is implemented at the ONU with the help of a single-drive MZM placed after Gaussian filter in every channel. With taking the assumed values of power, the estimated average ONU electrical power is 1.1 W, corresponding to ∼45 % electrical energy saving.

The elevated craving for exorbitant data transmission rates has conspicuously navigated noteworthy developments in fiber optic communication systems by concentrating on nonlinear optical phenomena. This research through inspection conveys an in-depth analysis of substantial nonlinear phenomena in optical fibers, including self-phase modulation (SPM), cross-phase modulation (XPM), self-steepening (SS), and four-wave mixing (FWM). The nonlinear refractive index of optical fibers engenders these phenomena, which greatly contribute to the capabilities and impediments of high-capacity Lightwave systems. While these nonlinearities may diminish signal quality via repercussions like signal distortion and noise, they can also be harnessed to elevate network efficiency through sophisticated mechanisms like dispersion control and pulse shaping. Through OptiSystem simulations, this indagation scrutinizes the ascendancy of SPM, XPM, SS, and FWM on the potential of optical communication systems, with a pivot on amplifying signal integrity and transmission efficiency. This probe examines ingenious perspectives to diminish deleterious nonlinear effects and meliorate system designs. Understanding these nonlinear processes permits the foundation of everlasting high-speed optical networks that can accommodate the proliferate exigency of current communication systems. By synthesizing insights into the behavior and management of nonlinear effects, this research succor to the inauguration of next-generation optical networks, which are vivacious for aggrandizing the inclusive efficiency and reliability of data transmission. The outcome accentuates the exigency of incorporating nonlinearities in the establishment and revamping of fiber optic systems, in due course paving the conduct for better efficient and reliable communication infrastructures. The investigation explores sophisticated mitigation strategies to ameliorate the performance and reliability of fiber optic networks. Optimized dispersion correction systems, including chirped fiber Bragg gratings, dispersion-compensating fibers, and digital signal processing (DSP)-based algorithms, recognize exact compensation for both linear and nonlinear dispersion effects. The utilization of sophisticated modulation formats such as orthogonal frequency division multiplexing, quadrature amplitude modulation, and carrier less amplitude phase modulation enhances spectral efficiency, mitigates noise, and reduces nonlinear interactions. Nonlinear compensation approaches, including optical phase conjugation, Volterra series-based DSP algorithms, and machine learning-based dynamic corrections, permit real-time reversal of nonlinear impairments. Furthermore, Raman amplification, large-core fibers, and power-level optimization ceiling nonlinear noise accretion. For solving crucial difficulties such as inter-channel crosstalk, spectrum widening, and timing jitter, solutions such as digital backpropagation, adaptive polarization control, and phase-conjugated twin waves are dispensed. Artificial intelligence (AI) based models, including neural networks, reinforcement learning, and hybrid AI-DSP frameworks, purvey predictive, adaptive management of nonlinearities in real time. Quantum technologies, utilizing quantum algorithms, variational quantum eigen solvers, and quantum machine learning, equip computational advances for effective modeling and optimization of nonlinear processes. These propounded techniques, along with hardware accelerations and scalable network optimizations, empower next-generation optical communication systems with ultra-high capacity, low BER, durable signal integrity, and considerable procurement in energy economy.

In satisfying the world bandwidth demand, wavelength division multiplexing (WDM) technology has gained paramount importance for modern telecommunication networks. Here, WDM provides simultaneous transmission of multiple data streams in one optical fiber, utilizing the high bandwidth capacity of optical fibers to answer the immense growth in data traffic. This paper presents the new WDM architecture with OADM, dynamic bandwidth allocation, and system performance monitoring for optimal utilization of the entire optical communication systems. Dynamic allocation of optical resources using the tunability of WDM permits enhanced flexibility for bandwidth reconfiguration and reduced operational costs. OADMs allow for the drop and add of a wavelength on demand, thereby providing an efficient mechanism for forwarding traffic through point-to-point, multicast, and mesh network topologies. These features greatly enhance the scalability and survivability of optical networks, especially with the advent of the next generation of broadband services such as video conferencing and distance learning.

Passive optical networks (PON) have transformed network access by offering cost-effective deployment, high-speed connectivity, scalability, and low power consumption. Integrating optical and wireless networks further enhances mobility and capacity while reducing operational costs. Radio over fiber (RoF) systems efficiently connect base stations to a central station via optical fibers but suffer from issues like high bit error rates (BER) and low Q-factor values. Wavelength division multiplexing (WDM) addresses these challenges by transmitting multiple signals over a single-mode fiber. This study simulates WDM-RoF performance under varying fiber lengths and channel spacings using OptiSystem, analyzing BER, Q-factor, and eye diagrams. To combat attenuation, semiconductor optical amplifier (SOA) and erbium-doped fiber amplifier (EDFA) are evaluated in a fixed ring topology. Results identify optimal configurations for improved signal efficiency and long-distance transmission, visualized using MATLAB.

The facial emotion recognition and alert system discussed in this paper align with several SDGs, including SDG 3 (Good Health and Well-Being), SDG 5 (Gender Equality), and SDG 16 (Peace, Justice, and Strong Institutions). This technology has the potential to improve mental health outcomes by allowing for early detection of emotional distress, particularly for marginalized communities who may not have access to mental health resources. Additionally, the use of this technology in security and surveillance systems could improve public safety and prevent violent incidents. However, it is important to ensure that the use of this technology is ethically and transparently implemented to avoid misuse and violation of privacy rights.

AbstractFSO (free space optical) communication holds emanated position in the role of propitious innovation with exorbitant-speed using the data transmission mechanism without the wire, propounding an accomplishable explication to the surging need for bandwidth in communication networks. This research paper probes into the improvements and obstacles in FSO communication systems, pursuing to anticipate a compendious encapsulation of the state-of-the-art establishment in this discipline. The evaluation incorporates a meticulous inspection of vital constituents such as laser sources, modulators, and receivers, elucidating their contribution to accomplishing coherent data transfer. The scrutinizing also investigates innumerable atmospheric circumstances affecting FSO links, including weather conditions and turbulence, and puts forward ingenious approaches to alleviate their repercussion on communication performance. Furthermore, the paper explores the homogenization of ultra-modern signal processing techniques to amplify the credibility and robustness of FSO systems, corroborating seamless communication even in challenging environments. Moreover, the research inquiries into the neoteric experimental framework and real-world execution of FSO communication, shedding light on heuristic contemplation, and substantiating theoretical unearthing. The conclusion of this research shells out treasures perception of the ongoing attempt to optimize FSO communication for variegated applications, including, inter-satellite communication, high-speed internet access, and last-mile connectivity. As FSO perpetuates progress, this paper suffices as a recent and inclusive resource for researchers, engineers, and policymakers maneuvering the edges of optical communication technologies.

AbstractThe explosive growth of worldwide mobile data traffic seeks innovations in communication technology to cater to the mounting need for rapid connectivity, high-capacity connections. The mainstreaming of 5G technologies for communication is a dramatic step towards meeting the aforementioned goals, with the ability for reshaping IoT (Internet of things), D2D (device-to-Device) communications, and the smart grids. This work conveys an in-depth study of the fundamental innovations that underlie 5G, including full-duplex distribution, huge multiple-input-multiple-output, ultra-dense connections, the phenomenon of beamforming and millimeter-wave approaches. A special emphasis is focused on the integration of photonic technologies, or microwave photonics, which serves as a critical multidisciplinary study topic. Optical fibers, with their tremendous bandwidth and capacity, have been determined as the best medium for backhaul and fronthaul amenities, outpacing conventional copper cables to accommodate tiny cells and next-generation networks. The synergy between optical and wireless access technologies is analyzed with the emphasis on the central role of wavelength-division multiplexing (WDM) for improving network efficiency and speed. The investigation additionally explores the possibility of intelligent signal processing methods combined with WDM to optimize photonic network communications. The mingling of these technologies anticipates producing unrivaled levels of performance, rupturing the path for an additional intelligent, interconnected era.