In this paper, we investigated the Coherent Optical Transmission System (COTS) performance for multiple types of DP-QAM levels considering various CW laser input power. We compared the performance of COTS for 100 Gb/s with DP-32QAM, DP-64QAM and DP-128QAM respectively. We also inspected the relationship among Optical Signal to Noise Ratio (OSNR), Error Vector Magnitude (EVM) and Bit Error Rate (BER) which are found in accordance for both simulation curves and constellation diagrams. Results are obtained by experiments with DP-32QAM, DP64QAM and DP-128QAM modulations techniques at symbol rate of 10 Gsymbol/s, 8.33 Gsymbol/s and 7.142 Gsymbol/s respectively. This work is completely based on simulation in Optisystem simulation setup.
This document summarizes a research paper on outage performance in MIMO free-space optical communication systems over gamma-gamma fading channels. The paper derives a closed-form expression for outage probability that accounts for the effects of inner scale size and aperture averaging. Simulation results show that increasing the number of transmit and receive apertures reduces the impact of inner scale size by providing spatial diversity. The conclusion is that MIMO systems can effectively mitigate the degradation caused by inner scale in moderate turbulence, but not completely in strong turbulence conditions.
Free space optical communication (FSO)JoshwavSunny
This document provides an overview of free space optical communication (FSO). It begins with an introduction that defines FSO as the transmission of visible and infrared beams through the atmosphere to achieve optical communications. It then discusses the history and existing fiber optic systems. The document outlines the advantages of FSO such as low cost, high security, and rapid deployment. It also discusses challenges like weather effects and limitations in range. Applications mentioned include enterprise connectivity, military/government use, and disaster management. The conclusion states that FSO provides a promising supplemental technology to wireless and fiber optic networks.
The document describes a lesson plan for a digital communication course at Matrusri Engineering College. The lesson plan covers linear block codes, including their description, generation, syndrome detection, minimum distance, error correction capabilities, and decoding using standard arrays and Hamming codes over 10 class periods. The objectives are to distinguish different error control coding techniques and their encoding/decoding algorithms. Textbooks and references are also listed.
This document discusses multiple-input multiple-output (MIMO) systems. It begins by outlining the motivations and aspirations for developing MIMO systems, including achieving high data rates near 1 gigabit/second while maintaining quality of service. It then provides an overview of MIMO system modeling and capacity studies. Key topics covered include diversity versus spatial multiplexing design criteria, example architectures, MIMO with orthogonal frequency-division multiplexing, and networking applications involving MAC protocols.
The document summarizes free space optical communication (FSO). It discusses the operation of FSO links, their advantages over fiber and microwave links, and applications. The key points are:
1. An FSO link consists of a transmitter, receiver, and tracking system to direct light beams between nodes. It allows license-free, high-speed connections but is susceptible to weather.
2. Applications include point-to-point links between buildings and potential mesh networks or use on high altitude platforms. Mesh networks provide better coverage but at a higher cost than point-to-point links.
3. Compared to fiber and microwave links, FSO systems have lower costs and power needs but higher data rates and
This document discusses optical fiber connectors. It begins by introducing the ferrule, which is a cylindrical tube used in connectors to precisely align the fiber cores. The document then covers the major types of connectors that have been introduced, including ST, SC, LC, FC, MU, and MPO connectors. ST and SC connectors became dominant in the 1980s-1990s due to their low loss and ease of use. Newer connectors like LC and MPO provide higher density by reducing size and combining multiple fibers. Proper connectors are important for achieving low insertion loss while providing easy installation and connection/disconnection of fibers.
1. The document discusses free space optical communication (FSO), which uses lasers to transmit data through the air instead of cables.
2. FSO has several advantages over traditional wired networks like fiber optics, including lower costs, easier installation, and no licensing requirements.
3. However, FSO also faces challenges from atmospheric effects like fog, rain, and scintillation that can disrupt the laser beam and degrade the quality of the transmission. Proper system design is needed to mitigate these effects.
Free-space optical (FSO) communication uses visible light or infrared light beams to transmit data through the air. It works similarly to fiber optics but transmits the light beam through the air instead of glass fibers. FSO systems can transmit data at rates similar to fiber optics over distances up to a few kilometers. They provide a wireless complement to radio-based communication systems. The main requirements are having an unobstructed line-of-sight between the transmitter and receiver and clear atmospheric conditions.
This document summarizes a research paper on outage performance in MIMO free-space optical communication systems over gamma-gamma fading channels. The paper derives a closed-form expression for outage probability that accounts for the effects of inner scale size and aperture averaging. Simulation results show that increasing the number of transmit and receive apertures reduces the impact of inner scale size by providing spatial diversity. The conclusion is that MIMO systems can effectively mitigate the degradation caused by inner scale in moderate turbulence, but not completely in strong turbulence conditions.
Free space optical communication (FSO)JoshwavSunny
This document provides an overview of free space optical communication (FSO). It begins with an introduction that defines FSO as the transmission of visible and infrared beams through the atmosphere to achieve optical communications. It then discusses the history and existing fiber optic systems. The document outlines the advantages of FSO such as low cost, high security, and rapid deployment. It also discusses challenges like weather effects and limitations in range. Applications mentioned include enterprise connectivity, military/government use, and disaster management. The conclusion states that FSO provides a promising supplemental technology to wireless and fiber optic networks.
The document describes a lesson plan for a digital communication course at Matrusri Engineering College. The lesson plan covers linear block codes, including their description, generation, syndrome detection, minimum distance, error correction capabilities, and decoding using standard arrays and Hamming codes over 10 class periods. The objectives are to distinguish different error control coding techniques and their encoding/decoding algorithms. Textbooks and references are also listed.
This document discusses multiple-input multiple-output (MIMO) systems. It begins by outlining the motivations and aspirations for developing MIMO systems, including achieving high data rates near 1 gigabit/second while maintaining quality of service. It then provides an overview of MIMO system modeling and capacity studies. Key topics covered include diversity versus spatial multiplexing design criteria, example architectures, MIMO with orthogonal frequency-division multiplexing, and networking applications involving MAC protocols.
The document summarizes free space optical communication (FSO). It discusses the operation of FSO links, their advantages over fiber and microwave links, and applications. The key points are:
1. An FSO link consists of a transmitter, receiver, and tracking system to direct light beams between nodes. It allows license-free, high-speed connections but is susceptible to weather.
2. Applications include point-to-point links between buildings and potential mesh networks or use on high altitude platforms. Mesh networks provide better coverage but at a higher cost than point-to-point links.
3. Compared to fiber and microwave links, FSO systems have lower costs and power needs but higher data rates and
This document discusses optical fiber connectors. It begins by introducing the ferrule, which is a cylindrical tube used in connectors to precisely align the fiber cores. The document then covers the major types of connectors that have been introduced, including ST, SC, LC, FC, MU, and MPO connectors. ST and SC connectors became dominant in the 1980s-1990s due to their low loss and ease of use. Newer connectors like LC and MPO provide higher density by reducing size and combining multiple fibers. Proper connectors are important for achieving low insertion loss while providing easy installation and connection/disconnection of fibers.
1. The document discusses free space optical communication (FSO), which uses lasers to transmit data through the air instead of cables.
2. FSO has several advantages over traditional wired networks like fiber optics, including lower costs, easier installation, and no licensing requirements.
3. However, FSO also faces challenges from atmospheric effects like fog, rain, and scintillation that can disrupt the laser beam and degrade the quality of the transmission. Proper system design is needed to mitigate these effects.
Free-space optical (FSO) communication uses visible light or infrared light beams to transmit data through the air. It works similarly to fiber optics but transmits the light beam through the air instead of glass fibers. FSO systems can transmit data at rates similar to fiber optics over distances up to a few kilometers. They provide a wireless complement to radio-based communication systems. The main requirements are having an unobstructed line-of-sight between the transmitter and receiver and clear atmospheric conditions.
The document discusses various transmission characteristics of optical fibers, including different types of losses that cause signal attenuation. It covers material absorption losses from intrinsic factors like Rayleigh scattering and extrinsic factors like metallic ion impurities. Other losses covered include scattering losses from inhomogeneities, bending losses when fibers are sharply bent, and dispersion where pulse spreading occurs over fiber lengths. The maximum bit rate for optical transmission is limited by dispersion effects.
The document discusses the medium access control sub layer and various protocols used for channel allocation in computer networks, including ALOHA, carrier sense multiple access, collision-free protocols, and Ethernet. It describes how these protocols handle situations where multiple devices attempt to access shared network resources simultaneously to avoid collisions. Key aspects covered include how the protocols determine which device gets to use the channel, detect collisions, and retransmit frames when collisions occur to maximize throughput.
VSAT technology allows for two-way communication via satellite using small terminals. A VSAT network consists of a central hub, satellite, and numerous user terminals. VSAT networks can support internet, data, video, voice, and private/public network solutions. They are becoming increasingly popular due to their flexibility, cost efficiency, and ability to quickly provide telecom solutions for consumers and businesses.
This document discusses various channel estimation techniques for OFDM systems. It describes pilot structures like block, comb and lattice types and how they are suited for different channel conditions. It also explains training symbol based channel estimation techniques like LS and MMSE. DFT-based channel estimation aims to improve performance by eliminating noise outside the channel delay. Decision directed channel estimation updates the channel coefficients without pilots by using detected signal feedback.
Includes a briefing on medium and high speed modems.Information about training sequence,scrambler and descrambler circuits.Also includes an introduction to modem control.
This document describes a course on topics in digital communications from June 2013 to February 2014. The course covers channel estimation techniques for various channel models, including single-tap channels and intersymbol interference channels. It discusses estimating channel coefficients using pilot symbols and maximum likelihood estimation. Channel estimation is applied to tasks such as symbol demodulation, equalization, and echo cancellation.
The document discusses various propagation mechanisms that affect radio signals, including reflection, diffraction, scattering, and their effects on signal strength over distance. It also covers propagation models like free space path loss, two-ray ground reflection model, and log-distance path loss for estimating average received signal power at a given distance. Fresnel zones and knife-edge diffraction are explained as factors in signal propagation around obstructions. Log-normal shadowing is described as a statistical model to account for variations from the average path loss.
OFC Unit 1 Optical Fiber Communication Introductiondeepraj adhikary
1. Optical fiber communication uses optical fibers to transmit data as light signals. Optical fibers have advantages over metallic wires like larger bandwidth and lower transmission losses.
2. Light propagation in optical fibers is based on the principles of total internal reflection. Light rays entering the fiber at an angle lower than the critical angle undergo total internal reflection.
3. Electromagnetic mode theory treats light as an electromagnetic wave rather than rays. Different modes of propagation exist depending on the fiber structure. The fundamental mode in cylindrical fibers is the LP01 mode.
1. Prioritizing handoffs over new call requests reduces the rate of handoff failures, which is desirable from the user's perspective.
2. There are two main methods for prioritizing handoffs - using guard channels that are reserved exclusively for handoff requests, and queuing handoff requests to be served before new calls.
3. The guard channel method reserves a fraction of available channels for handoffs, reducing the number of required guard channels and offering more efficient spectrum utilization. However, it has the disadvantage of reducing total carried traffic. Queuing handoff requests puts them in a queue to be served first on a first-come, first-served basis, reducing failed handoffs but also reducing
Erbium-doped fiber amplifiers (EDFAs) were invented in 1987 at the University of Southampton. Erbium ions allow for amplification in the 1540nm band with low fiber loss. Erbium can be excited by 980nm or 1480nm pumps carried by fiber. EDFAs provide high gain, low noise figure, and bit rate transparency for wavelength division multiplexing. They require pump lasers but do not need high-speed electronics.
This document provides an overview of wavelength division multiplexing (WDM) technology. It begins with introducing optical fibers and their components. It then discusses multiplexing techniques like time-division multiplexing (TDM) and frequency-division multiplexing (FDM). The document focuses on WDM, defining it as a technology that multiplexes multiple optical signals on a single fiber using different laser light wavelengths. It describes dense WDM (DWDM) and coarse WDM (CWDM), and compares their wavelength spacing and applications. The document also outlines optical amplifiers like erbium-doped fiber amplifiers and their uses. In conclusion, it states that WDM enables high-speed, high-capacity data transmission and
This document discusses the design of terrestrial microwave links. It begins with an introduction to microwave links and their basic components - transmitters, towers, antennas, and receivers. Antennas must have line-of-sight between sites. The document then covers topics like frequency standards, polarization, antenna types, link budgets, and operating frequencies. It provides block diagrams of transmitter and receiver base stations. Key components like mixers, filters, amplifiers and their functions are described. Signal spreading in W-CDMA systems is also explained. Technical characteristics of microwave point-to-point links are outlined.
Signal and image processing on satellite communication using MATLABEmbedded Plus Trichy
Basic Explanations about satellite imaging and signal processing with the help of MATLAB.
Contact us: 23,Nandhi koil Street, Near Nakoda Showroom,Theppakulam,Trichy
Mb.No:9360212155.
Mail:embeddedplusproject@gmail.com,
FB:www.facebook.com/embeddedplusproject
The document discusses link budget analysis for satellite communications. Link budget is used to optimize satellite link performance given limited transponder power and bandwidth. It involves understanding parameters like transponder bandwidth, satellite gain, transmit power, modulation, coding, and receiver sensitivity to estimate required capacity and improve link quality. Key factors that impact the link budget calculation are discussed in detail.
This document discusses MIMO (multiple-input multiple-output) communication systems which use multiple antennas at the transmitter and receiver. It describes the mathematical model of MIMO and compares it to previous technologies like SISO and MIMO. The key benefits of MIMO are that it can increase data rates using spatial multiplexing and improve reliability using diversity techniques. MIMO systems are used in wireless technologies like 3G, WiMAX, and LTE.
This document discusses radio propagation and propagation models. It begins with an introduction to radio and propagation mechanisms like free space propagation, refraction, diffraction, and scattering. It then discusses the objective of developing propagation models to predict signal strength at a receiver. The document outlines that propagation models are specialized based on scale, environment, and application. It covers large-scale path loss models and small-scale fading models. It discusses specific propagation mechanisms and models like free space, log-distance path loss, ground reflection, hilly terrain, indoor models, and statistical fading models.
WDM (wavelength-division multiplexing) allows multiple optical signals at different wavelengths to be transmitted simultaneously over the same optical fiber. Key components of WDM systems include multiplexers that combine signals and demultiplexers that separate them. Passive components like fiber couplers split and combine light streams without converting to electrical signals. 2x2 fiber couplers fuse two fibers together, allowing a portion of light from one fiber to couple to the other based on length and properties of the fused region. Waveguide couplers also combine light between neighboring waveguides based on their properties and length.
Coded OFDM in Fiber-Optics Communication Systems with Optimum biasing of LaserCSCJournals
Abstract----A novel high spectral efficiency all-optical sampling orthogonal frequency-division multiplexing scheme is proposed using space frequency Block coding (SFBC) techniques and nonlinear behavior of vertical-cavity surface-emitting laser diodes is exploited by relative intensity to noise (RIN).We show that in long-haul fiber optics communications, SFBC-coded OFDM increases spectral efficiency and reduces the influence of chromatic dispersion in optical-OFDM system if RIN is adjusted to -155 dB/Hz
The document discusses Coherent Optical OFDM (CO-OFDM) and analyzes its performance at different data rates such as 1Gbps, 20Gbps, and 100Gbps. 4QAM-OFDM signals are generated and transmitted through 250km of fiber. The results show that distortions in the OFDM spectrum and QAM constellations increase as the data rate increases, due to nonlinearities in the fiber. CO-OFDM has advantages over other modulation formats as it provides both coherent detection and OFDM modulation, but its performance is affected by fiber nonlinearities at high data rates due to its high peak-to-average power ratio.
The document discusses various transmission characteristics of optical fibers, including different types of losses that cause signal attenuation. It covers material absorption losses from intrinsic factors like Rayleigh scattering and extrinsic factors like metallic ion impurities. Other losses covered include scattering losses from inhomogeneities, bending losses when fibers are sharply bent, and dispersion where pulse spreading occurs over fiber lengths. The maximum bit rate for optical transmission is limited by dispersion effects.
The document discusses the medium access control sub layer and various protocols used for channel allocation in computer networks, including ALOHA, carrier sense multiple access, collision-free protocols, and Ethernet. It describes how these protocols handle situations where multiple devices attempt to access shared network resources simultaneously to avoid collisions. Key aspects covered include how the protocols determine which device gets to use the channel, detect collisions, and retransmit frames when collisions occur to maximize throughput.
VSAT technology allows for two-way communication via satellite using small terminals. A VSAT network consists of a central hub, satellite, and numerous user terminals. VSAT networks can support internet, data, video, voice, and private/public network solutions. They are becoming increasingly popular due to their flexibility, cost efficiency, and ability to quickly provide telecom solutions for consumers and businesses.
This document discusses various channel estimation techniques for OFDM systems. It describes pilot structures like block, comb and lattice types and how they are suited for different channel conditions. It also explains training symbol based channel estimation techniques like LS and MMSE. DFT-based channel estimation aims to improve performance by eliminating noise outside the channel delay. Decision directed channel estimation updates the channel coefficients without pilots by using detected signal feedback.
Includes a briefing on medium and high speed modems.Information about training sequence,scrambler and descrambler circuits.Also includes an introduction to modem control.
This document describes a course on topics in digital communications from June 2013 to February 2014. The course covers channel estimation techniques for various channel models, including single-tap channels and intersymbol interference channels. It discusses estimating channel coefficients using pilot symbols and maximum likelihood estimation. Channel estimation is applied to tasks such as symbol demodulation, equalization, and echo cancellation.
The document discusses various propagation mechanisms that affect radio signals, including reflection, diffraction, scattering, and their effects on signal strength over distance. It also covers propagation models like free space path loss, two-ray ground reflection model, and log-distance path loss for estimating average received signal power at a given distance. Fresnel zones and knife-edge diffraction are explained as factors in signal propagation around obstructions. Log-normal shadowing is described as a statistical model to account for variations from the average path loss.
OFC Unit 1 Optical Fiber Communication Introductiondeepraj adhikary
1. Optical fiber communication uses optical fibers to transmit data as light signals. Optical fibers have advantages over metallic wires like larger bandwidth and lower transmission losses.
2. Light propagation in optical fibers is based on the principles of total internal reflection. Light rays entering the fiber at an angle lower than the critical angle undergo total internal reflection.
3. Electromagnetic mode theory treats light as an electromagnetic wave rather than rays. Different modes of propagation exist depending on the fiber structure. The fundamental mode in cylindrical fibers is the LP01 mode.
1. Prioritizing handoffs over new call requests reduces the rate of handoff failures, which is desirable from the user's perspective.
2. There are two main methods for prioritizing handoffs - using guard channels that are reserved exclusively for handoff requests, and queuing handoff requests to be served before new calls.
3. The guard channel method reserves a fraction of available channels for handoffs, reducing the number of required guard channels and offering more efficient spectrum utilization. However, it has the disadvantage of reducing total carried traffic. Queuing handoff requests puts them in a queue to be served first on a first-come, first-served basis, reducing failed handoffs but also reducing
Erbium-doped fiber amplifiers (EDFAs) were invented in 1987 at the University of Southampton. Erbium ions allow for amplification in the 1540nm band with low fiber loss. Erbium can be excited by 980nm or 1480nm pumps carried by fiber. EDFAs provide high gain, low noise figure, and bit rate transparency for wavelength division multiplexing. They require pump lasers but do not need high-speed electronics.
This document provides an overview of wavelength division multiplexing (WDM) technology. It begins with introducing optical fibers and their components. It then discusses multiplexing techniques like time-division multiplexing (TDM) and frequency-division multiplexing (FDM). The document focuses on WDM, defining it as a technology that multiplexes multiple optical signals on a single fiber using different laser light wavelengths. It describes dense WDM (DWDM) and coarse WDM (CWDM), and compares their wavelength spacing and applications. The document also outlines optical amplifiers like erbium-doped fiber amplifiers and their uses. In conclusion, it states that WDM enables high-speed, high-capacity data transmission and
This document discusses the design of terrestrial microwave links. It begins with an introduction to microwave links and their basic components - transmitters, towers, antennas, and receivers. Antennas must have line-of-sight between sites. The document then covers topics like frequency standards, polarization, antenna types, link budgets, and operating frequencies. It provides block diagrams of transmitter and receiver base stations. Key components like mixers, filters, amplifiers and their functions are described. Signal spreading in W-CDMA systems is also explained. Technical characteristics of microwave point-to-point links are outlined.
Signal and image processing on satellite communication using MATLABEmbedded Plus Trichy
Basic Explanations about satellite imaging and signal processing with the help of MATLAB.
Contact us: 23,Nandhi koil Street, Near Nakoda Showroom,Theppakulam,Trichy
Mb.No:9360212155.
Mail:embeddedplusproject@gmail.com,
FB:www.facebook.com/embeddedplusproject
The document discusses link budget analysis for satellite communications. Link budget is used to optimize satellite link performance given limited transponder power and bandwidth. It involves understanding parameters like transponder bandwidth, satellite gain, transmit power, modulation, coding, and receiver sensitivity to estimate required capacity and improve link quality. Key factors that impact the link budget calculation are discussed in detail.
This document discusses MIMO (multiple-input multiple-output) communication systems which use multiple antennas at the transmitter and receiver. It describes the mathematical model of MIMO and compares it to previous technologies like SISO and MIMO. The key benefits of MIMO are that it can increase data rates using spatial multiplexing and improve reliability using diversity techniques. MIMO systems are used in wireless technologies like 3G, WiMAX, and LTE.
This document discusses radio propagation and propagation models. It begins with an introduction to radio and propagation mechanisms like free space propagation, refraction, diffraction, and scattering. It then discusses the objective of developing propagation models to predict signal strength at a receiver. The document outlines that propagation models are specialized based on scale, environment, and application. It covers large-scale path loss models and small-scale fading models. It discusses specific propagation mechanisms and models like free space, log-distance path loss, ground reflection, hilly terrain, indoor models, and statistical fading models.
WDM (wavelength-division multiplexing) allows multiple optical signals at different wavelengths to be transmitted simultaneously over the same optical fiber. Key components of WDM systems include multiplexers that combine signals and demultiplexers that separate them. Passive components like fiber couplers split and combine light streams without converting to electrical signals. 2x2 fiber couplers fuse two fibers together, allowing a portion of light from one fiber to couple to the other based on length and properties of the fused region. Waveguide couplers also combine light between neighboring waveguides based on their properties and length.
Coded OFDM in Fiber-Optics Communication Systems with Optimum biasing of LaserCSCJournals
Abstract----A novel high spectral efficiency all-optical sampling orthogonal frequency-division multiplexing scheme is proposed using space frequency Block coding (SFBC) techniques and nonlinear behavior of vertical-cavity surface-emitting laser diodes is exploited by relative intensity to noise (RIN).We show that in long-haul fiber optics communications, SFBC-coded OFDM increases spectral efficiency and reduces the influence of chromatic dispersion in optical-OFDM system if RIN is adjusted to -155 dB/Hz
The document discusses Coherent Optical OFDM (CO-OFDM) and analyzes its performance at different data rates such as 1Gbps, 20Gbps, and 100Gbps. 4QAM-OFDM signals are generated and transmitted through 250km of fiber. The results show that distortions in the OFDM spectrum and QAM constellations increase as the data rate increases, due to nonlinearities in the fiber. CO-OFDM has advantages over other modulation formats as it provides both coherent detection and OFDM modulation, but its performance is affected by fiber nonlinearities at high data rates due to its high peak-to-average power ratio.
Analysis of Nonlinear Signal Interference to Optimize the Coherent Optical Tr...IOSRJECE
In this paper we analyze the power of Nonlinear Signal Inference ( NLSI p ) and optimize the coherent optical transmission system (COTS) based on PM-16QAM higher modulation format for different baud rates considering commercially available silica fiber (SF). Theoretically, this work follows up four Gaussian Noise (GN) models depending on multiple identical spans, non-Nyquist WDM system, non-identical spans and multichannels to confirm the better accuracy of these models. The most fitted model is then used to optimize the COTS achieved by analyzing the Amplified Spontaneous Emission noise power (PASE) to determine the optimum Optical Signal to Noise Ratio (OSNR). Matlab R2011b simulation tool is run here to generate the OSNR and Bit Error Rate (BER) performance curves for the COTS. The OSNR has been simulated considering input transmitting power per span, span length, dispersion and fiber loss coefficient. Results show that, the OSNR penalty is around 3dB and 6dB when line rate is multiplied with the factor of 2xbit rate, 4x bit rate respectively for same modulation and demodulation formats in the COTS.
This document describes a simulation of an optical orthogonal frequency division multiplexing (OFDM) system using different M-ary quadrature amplitude modulation (QAM) techniques. The performance of the system was evaluated in terms of bit error rate (BER) and signal-to-noise ratio (SNR) by varying the modulation order M to 16, 64, and 256. Simulation results showed that higher modulation orders require higher SNR values to achieve the same BER as lower modulation orders. The simulated results closely matched theoretical predictions, though there was a deviation of 3-3.5 dB, likely due to additional noise and losses not accounted for in the theoretical model.
Designing and Performance Evaluation of 64 QAM OFDM SystemIOSR Journals
Abstract (11Bold) : — In this report, the performance analysis of 64 QAM-OFDM wireless communication
systems affected by AWGN in terms of Symbol Error Rate and Throughput is addressed. 64 QAM (64 ary
Quadrature Amplitude Modulation) is the one of the effective digital modulation technique as it is more power
efficient for larger values of M(64). The MATLAB script based model of the 64 QAM-OFDM system with
normal AWGN channel and Rayleigh fading channel has been made for study error performance and
throughput under different channel conditions. This simulated model maximizes the system throughput in the
presence of narrowband interference, while guaranteeing a SER below a predefined threshold. The SER
calculation is accomplished by means of modelling the decision variable at the receiver as a particular case of
quadratic form D in complex Gaussian random variables. Lastly comparative study of SER performance of 64
QAM-OFDM simulated & 64 QAM-OFDM theoretical under AWGN channel has been given. Also
performance of the system is given in terms of throughput (received bits/ofm symbol) is given in a plot for
different SNR. Keywords (11Bold) –64 QAM, BPSK, OFDM, PDF, SNR.
Designing and Performance Evaluation of 64 QAM OFDM SystemIOSR Journals
In this report, the performance analysis of 64 QAM-OFDM wireless communication
systems affected by AWGN in terms of Symbol Error Rate and Throughput is addressed. 64 QAM (64 ary
Quadrature Amplitude Modulation) is the one of the effective digital modulation technique as it is more power
efficient for larger values of M(64). The MATLAB script based model of the 64 QAM-OFDM system with
normal AWGN channel and Rayleigh fading channel has been made for study error performance and
throughput under different channel conditions. This simulated model maximizes the system throughput in the
presence of narrowband interference, while guaranteeing a SER below a predefined threshold. The SER
calculation is accomplished by means of modelling the decision variable at the receiver as a particular case of
quadratic form D in complex Gaussian random variables. Lastly comparative study of SER performance of 64
QAM-OFDM simulated & 64 QAM-OFDM theoretical under AWGN channel has been given. Also
performance of the system is given in terms of throughput (received bits/ofm symbol) is given in a plot for
different SNR
Hybrid Adaptive Channel Estimation Technique in Time and Frequency Domain for...Tamilarasan N
This document summarizes a research paper that proposes a hybrid adaptive channel estimation technique for MIMO-OFDM wireless communication systems. The technique integrates channel estimation in the time domain and frequency domain. It uses column-based time domain estimation initially and switches to row-based frequency domain estimation when channel quality is good and bit error rate is low. It switches back to time domain estimation when channel quality worsens. The goal is to adaptively estimate the channel under different conditions. Experimental results showed the proposed hybrid technique outperformed other methods.
The document proposes a new channel estimation algorithm called ICEA-DA for MIMO-OFDM systems. ICEA-DA uses least squares estimation with discrete Fourier transform and integrates it with a differential evolution technique. It is placed at the central part of the MIMO-OFDM system between the transmitter and receiver blocks. The proposed method is evaluated for a 2x4 MIMO system using QPSK modulation. Results show ICEA-DA provides better performance than existing techniques in terms of bit error rate, peak signal-to-noise ratio, channel capacity, and symbol error rate.
This document analyzes the performance of M-QAM modulation in OFDM systems. It begins with an introduction to OFDM and how it addresses issues like intersymbol interference caused by multipath fading. It then describes M-QAM and M-PSK modulation schemes used in OFDM. Through MATLAB simulations, it evaluates the bit error rate performance of different modulation orders in AWGN and frequency selective Rayleigh fading channels. The results show that higher order QAM in OFDM provides better performance with lower bit error rates than PSK, especially at higher SNR values. Therefore, QAM is determined to be a better choice than PSK for high data rate transmission using OFDM.
This document analyzes the performance of an adaptive orthogonal frequency division multiplexing (OFDM) system over an additive white Gaussian noise (AWGN) channel. It considers the system's bit error rate (BER), mean square error (MSE), spectral efficiency, and throughput using binary phase-shift keying (BPSK), quadrature phase-shift keying (QPSK), and quadrature amplitude modulation (QAM). The system adaptively selects the modulation scheme on each subcarrier based on instantaneous signal-to-noise ratio (SNR) measurements to improve performance. Simulation results show that higher order modulation is used at lower SNRs for better spectral efficiency, while lower modulation is used at higher SNRs to improve throughput. The adaptive
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...IJECEIAES
This paper addresses the performance analysis of OFDM transmission system based on coherent detection over high speed long haul optical links with high spectral efficiency modulation formats such as Quadrature Amplitude Modulation (QAM) as a mapping method prior to the OFDM multicarrier representation. Post compensation is used to compensate for phase noise effects. Coherent detection for signal transmitted at bit rate of 40 Gbps is successfully achieved up to distance of 3200km. Performance is analyzed in terms of Symbol Error Rate and Error Vector Magnitude by varying Optical Signal to Noise Ratio (OSNR) and varying the length of the fiber i.e transmission distance. Transmission performance is also observed through constellation diagrams at different transmission distances and different OSNRs.
Performance Analysis of Post Compensated Long Haul High Speed Coherent Optica...Yayah Zakaria
This paper addresses the performance analysis of OFDM transmission system based on coherent detection over high speed long haul optical links with high spectral efficiency modulation formats such as Quadrature Amplitude Modulation (QAM) as a mapping method prior to the OFDM multicarrier representation. Post compensation is used to compensate for
phase noise effects. Coherent detection for signal transmitted at bit rate of 40 Gbps is successfully achieved up to distance of 3200km. Performance is analyzed in terms of Symbol Error Rate and Error Vector Magnitude by varying Optical Signal to Noise Ratio (OSNR) and varying the length of the fiber i.e transmission distance. Transmission performance is also observed through constellation diagrams at different transmission distances and
different OSNRs.
Computer-Based Analysis of The Performance of Different Modulation Techniques...theijes
This document analyzes the performance of different modulation techniques in WCDMA systems with different channels. It compares M-PSK and M-Ary PAM modulation in Rayleigh fading and AWGN channels using MATLAB/Simulink. The results show that M-PAM in AWGN channels has lower bit error rates compared to M-PSK, while M-PSK in Rayleigh fading performs better than M-PAM. As modulation levels and simulation time increase, bit error rates also increase, though irregularly in Rayleigh fading channels. Overall, the best technique depends on the channel conditions and system requirements.
1) The document analyzes the effect of intercarrier interference (ICI) on single carrier orthogonal frequency division multiplexing (SC-OFDM) systems.
2) It proposes a novel magnitude-keyed modulation scheme that provides SC-OFDM immunity to ICI. This outperforms other modulation schemes like OFDM, SC-OFDM, and MC-CDMA that use phase shift keying or quadrature amplitude modulation in environments with severe ICI.
3) The analysis shows that the effect of ICI on SC-OFDM signals is simply a phase offset on each data symbol, whereas ICI introduces interference between subcarriers for OFDM. Therefore, SC-OFDM has significantly better performance
Comparative Analysis of DP QPSK and DP 16-QAM Optical Coherent Receiver, with...IRJET Journal
This document compares DP QPSK and DP 16-QAM optical coherent receivers in terms of average bit error rate (BER) when analyzing phase noise. It simulates a 112 Gbps DP 16-QAM and DP QPSK coherent receiver system with digital signal processing (DSP) using Optisystem and MATLAB. The analysis introduces noise before the receiver by varying the optical signal-to-noise ratio (OSNR) and measures average BER. Graphs of average BER versus OSNR are produced for different digital filters and filter orders to determine the filter with minimum phase noise. The DP 16-QAM system shows better power spectrum confinement and is analyzed in more detail.
Received Power performance in downlink architecture of Radio-over-Fiber Trans...IOSR Journals
Abstract : The In this paper, we studied the RoF system and analyzed the received power performance in downlink architecture of RoF system. The RoF system employs a Mach–Zehnder modulator (MZM) and a phase shifter to externally generate an optical single sideband (OSSB) signal since the OSSB signal is tolerable for power degradation due to a chromatic fiber-dispersion effect. The received power performance is analyzed by calculating a factor called Power Penalty. It is shown that Power penalty is increased exponentially as the differential delay increased with the distance due to chromatic dispersion with the change in laser linewidth (𝛾𝑅𝐹) from 10MHz to 1000MHz. The results are calculated for various transmission distances (𝐿𝐹𝐼𝐵𝐸𝑅) 1km to 40km for optical distances. The frequency of laser taken is 30-GHz RF carrier (𝑓𝑅𝐹) and wavelength 1550-nm laser (λ) with zero line width, fiber dispersion parameter (D) 17 ps/nm·km.
Keywords: Chromatic dispersion, DEMZM, Laser line width, Power penalty and Received power.
Performance evaluation of high mobility OFDM channel estimation techniques IJECEIAES
In wireless communication, Orthogonal Frequency Division Multiplexing (OFDM) has been adopted due to its robustness to multipath fading and high data rate transmissions. At the other hand, the performance of OFDM systems severely degraded due to multi-path fading and Doppler frequency shifts in mobile systems, which causes inter-carrier-interference (ICI). Thus, Estimation of channel parameters is required at the receiver using a pre designed estimator where pilot tones are inserted in each OFDM symbol. In this paper, a random pilot data are generated and inserted in each OFDM symbol at equally spaced locations. The performance test of Least Square (LS) and Linear Minimum Mean Square (LMMSE) estimation methods are proposed with Discrete Fourier Transform (DFT) based on both LS and LMMSE, where different ITU channel models are considered in order to compare their performance for data transmission in high mobile systems with different Doppler frequencies exceeds 200 Hz and minimal number of pilots.
Comparison of Three Different Cancellation Schemes for Orthogonal Frequency D...ijtsrd
Orthogonal Frequency Division Multiplexing OFDM is an exceptional case of Frequency Division Multiplexing. The dilemma of OFDM is its sensitivity to frequency offset between the transmitted and received carrier frequencies. This frequency offset establishes Inter Carrier Interference ICI Cancellation in the OFDM symbol. ICI reduction methods have been had by OFDM. This research considers three ICI self cancellation SC , maximum likelihood ML estimation, and extended Kalman filter EKF method. These three methods are compared in terms of bit error rate performance, bandwidth efficiency, and computational complexity. For high values of the frequency offset and for higher order modulation schemes, the SC method does not as well as the ML and EKF methods. Simulation results using MATLAB software. Ma Khin Saw | Aye Aye Khine ""Comparison of Three Different Cancellation Schemes for Orthogonal Frequency Division Multiplexing (OFDM) System"" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-4 , June 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25182.pdf
Paper URL: https://www.ijtsrd.com/engineering/electronics-and-communication-engineering/25182/comparison-of-three-different-cancellation-schemes-for-orthogonal-frequency-division-multiplexing-ofdm-system/ma-khin-saw
Investigation and Analysis of SNR Estimation in OFDM systemIOSR Journals
Estimation of signal to noise ratio (SNR) of received signal and to transmit the signal effectively for
the modern communication system. The performance of existing non-data-aided (NDA) SNR estimation methods
are substantially degraded for high level modulation scheme such as M-ary amplitude and phase shift keying
(APSK) or quadrature amplitude modulation (QAM).In this paper SNR estimation proposed method which uses
zero point auto-correlation of received signal per block and auto/cross- correlation of decision feedback signal
in orthogonal frequency division multiplexing (OFDM) system. Proposed method can be studied into two types;
Type 1 can estimate SNR by zero point auto-correlation of decision feedback signal based on the second
moment property. Type 2 uses both zero point auto-correlation and cross-correlation based on the fourth
moment property. In block-by-block reception of OFDM system, these two SNR estimation methods can be
possible for the practical implementation due to correlation based the estimation method and they show more
stable estimation performance than the earlier SNR estimation methods.
Similar to Comparison of coherent optical transmission systems performance by DP-QAM levels (20)
Redefining brain tumor segmentation: a cutting-edge convolutional neural netw...IJECEIAES
Medical image analysis has witnessed significant advancements with deep learning techniques. In the domain of brain tumor segmentation, the ability to
precisely delineate tumor boundaries from magnetic resonance imaging (MRI)
scans holds profound implications for diagnosis. This study presents an ensemble convolutional neural network (CNN) with transfer learning, integrating
the state-of-the-art Deeplabv3+ architecture with the ResNet18 backbone. The
model is rigorously trained and evaluated, exhibiting remarkable performance
metrics, including an impressive global accuracy of 99.286%, a high-class accuracy of 82.191%, a mean intersection over union (IoU) of 79.900%, a weighted
IoU of 98.620%, and a Boundary F1 (BF) score of 83.303%. Notably, a detailed comparative analysis with existing methods showcases the superiority of
our proposed model. These findings underscore the model’s competence in precise brain tumor localization, underscoring its potential to revolutionize medical
image analysis and enhance healthcare outcomes. This research paves the way
for future exploration and optimization of advanced CNN models in medical
imaging, emphasizing addressing false positives and resource efficiency.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Neural network optimizer of proportional-integral-differential controller par...IJECEIAES
Wide application of proportional-integral-differential (PID)-regulator in industry requires constant improvement of methods of its parameters adjustment. The paper deals with the issues of optimization of PID-regulator parameters with the use of neural network technology methods. A methodology for choosing the architecture (structure) of neural network optimizer is proposed, which consists in determining the number of layers, the number of neurons in each layer, as well as the form and type of activation function. Algorithms of neural network training based on the application of the method of minimizing the mismatch between the regulated value and the target value are developed. The method of back propagation of gradients is proposed to select the optimal training rate of neurons of the neural network. The neural network optimizer, which is a superstructure of the linear PID controller, allows increasing the regulation accuracy from 0.23 to 0.09, thus reducing the power consumption from 65% to 53%. The results of the conducted experiments allow us to conclude that the created neural superstructure may well become a prototype of an automatic voltage regulator (AVR)-type industrial controller for tuning the parameters of the PID controller.
An improved modulation technique suitable for a three level flying capacitor ...IJECEIAES
This research paper introduces an innovative modulation technique for controlling a 3-level flying capacitor multilevel inverter (FCMLI), aiming to streamline the modulation process in contrast to conventional methods. The proposed
simplified modulation technique paves the way for more straightforward and
efficient control of multilevel inverters, enabling their widespread adoption and
integration into modern power electronic systems. Through the amalgamation of
sinusoidal pulse width modulation (SPWM) with a high-frequency square wave
pulse, this controlling technique attains energy equilibrium across the coupling
capacitor. The modulation scheme incorporates a simplified switching pattern
and a decreased count of voltage references, thereby simplifying the control
algorithm.
A review on features and methods of potential fishing zoneIJECEIAES
This review focuses on the importance of identifying potential fishing zones in seawater for sustainable fishing practices. It explores features like sea surface temperature (SST) and sea surface height (SSH), along with classification methods such as classifiers. The features like SST, SSH, and different classifiers used to classify the data, have been figured out in this review study. This study underscores the importance of examining potential fishing zones using advanced analytical techniques. It thoroughly explores the methodologies employed by researchers, covering both past and current approaches. The examination centers on data characteristics and the application of classification algorithms for classification of potential fishing zones. Furthermore, the prediction of potential fishing zones relies significantly on the effectiveness of classification algorithms. Previous research has assessed the performance of models like support vector machines, naïve Bayes, and artificial neural networks (ANN). In the previous result, the results of support vector machine (SVM) were 97.6% more accurate than naive Bayes's 94.2% to classify test data for fisheries classification. By considering the recent works in this area, several recommendations for future works are presented to further improve the performance of the potential fishing zone models, which is important to the fisheries community.
Electrical signal interference minimization using appropriate core material f...IJECEIAES
As demand for smaller, quicker, and more powerful devices rises, Moore's law is strictly followed. The industry has worked hard to make little devices that boost productivity. The goal is to optimize device density. Scientists are reducing connection delays to improve circuit performance. This helped them understand three-dimensional integrated circuit (3D IC) concepts, which stack active devices and create vertical connections to diminish latency and lower interconnects. Electrical involvement is a big worry with 3D integrates circuits. Researchers have developed and tested through silicon via (TSV) and substrates to decrease electrical wave involvement. This study illustrates a novel noise coupling reduction method using several electrical involvement models. A 22% drop in electrical involvement from wave-carrying to victim TSVs introduces this new paradigm and improves system performance even at higher THz frequencies.
Electric vehicle and photovoltaic advanced roles in enhancing the financial p...IJECEIAES
Climate change's impact on the planet forced the United Nations and governments to promote green energies and electric transportation. The deployments of photovoltaic (PV) and electric vehicle (EV) systems gained stronger momentum due to their numerous advantages over fossil fuel types. The advantages go beyond sustainability to reach financial support and stability. The work in this paper introduces the hybrid system between PV and EV to support industrial and commercial plants. This paper covers the theoretical framework of the proposed hybrid system including the required equation to complete the cost analysis when PV and EV are present. In addition, the proposed design diagram which sets the priorities and requirements of the system is presented. The proposed approach allows setup to advance their power stability, especially during power outages. The presented information supports researchers and plant owners to complete the necessary analysis while promoting the deployment of clean energy. The result of a case study that represents a dairy milk farmer supports the theoretical works and highlights its advanced benefits to existing plants. The short return on investment of the proposed approach supports the paper's novelty approach for the sustainable electrical system. In addition, the proposed system allows for an isolated power setup without the need for a transmission line which enhances the safety of the electrical network
Bibliometric analysis highlighting the role of women in addressing climate ch...IJECEIAES
Fossil fuel consumption increased quickly, contributing to climate change
that is evident in unusual flooding and draughts, and global warming. Over
the past ten years, women's involvement in society has grown dramatically,
and they succeeded in playing a noticeable role in reducing climate change.
A bibliometric analysis of data from the last ten years has been carried out to
examine the role of women in addressing the climate change. The analysis's
findings discussed the relevant to the sustainable development goals (SDGs),
particularly SDG 7 and SDG 13. The results considered contributions made
by women in the various sectors while taking geographic dispersion into
account. The bibliometric analysis delves into topics including women's
leadership in environmental groups, their involvement in policymaking, their
contributions to sustainable development projects, and the influence of
gender diversity on attempts to mitigate climate change. This study's results
highlight how women have influenced policies and actions related to climate
change, point out areas of research deficiency and recommendations on how
to increase role of the women in addressing the climate change and
achieving sustainability. To achieve more successful results, this initiative
aims to highlight the significance of gender equality and encourage
inclusivity in climate change decision-making processes.
Voltage and frequency control of microgrid in presence of micro-turbine inter...IJECEIAES
The active and reactive load changes have a significant impact on voltage
and frequency. In this paper, in order to stabilize the microgrid (MG) against
load variations in islanding mode, the active and reactive power of all
distributed generators (DGs), including energy storage (battery), diesel
generator, and micro-turbine, are controlled. The micro-turbine generator is
connected to MG through a three-phase to three-phase matrix converter, and
the droop control method is applied for controlling the voltage and
frequency of MG. In addition, a method is introduced for voltage and
frequency control of micro-turbines in the transition state from gridconnected mode to islanding mode. A novel switching strategy of the matrix
converter is used for converting the high-frequency output voltage of the
micro-turbine to the grid-side frequency of the utility system. Moreover,
using the switching strategy, the low-order harmonics in the output current
and voltage are not produced, and consequently, the size of the output filter
would be reduced. In fact, the suggested control strategy is load-independent
and has no frequency conversion restrictions. The proposed approach for
voltage and frequency regulation demonstrates exceptional performance and
favorable response across various load alteration scenarios. The suggested
strategy is examined in several scenarios in the MG test systems, and the
simulation results are addressed.
Enhancing battery system identification: nonlinear autoregressive modeling fo...IJECEIAES
Precisely characterizing Li-ion batteries is essential for optimizing their
performance, enhancing safety, and prolonging their lifespan across various
applications, such as electric vehicles and renewable energy systems. This
article introduces an innovative nonlinear methodology for system
identification of a Li-ion battery, employing a nonlinear autoregressive with
exogenous inputs (NARX) model. The proposed approach integrates the
benefits of nonlinear modeling with the adaptability of the NARX structure,
facilitating a more comprehensive representation of the intricate
electrochemical processes within the battery. Experimental data collected
from a Li-ion battery operating under diverse scenarios are employed to
validate the effectiveness of the proposed methodology. The identified
NARX model exhibits superior accuracy in predicting the battery's behavior
compared to traditional linear models. This study underscores the
importance of accounting for nonlinearities in battery modeling, providing
insights into the intricate relationships between state-of-charge, voltage, and
current under dynamic conditions.
Smart grid deployment: from a bibliometric analysis to a surveyIJECEIAES
Smart grids are one of the last decades' innovations in electrical energy.
They bring relevant advantages compared to the traditional grid and
significant interest from the research community. Assessing the field's
evolution is essential to propose guidelines for facing new and future smart
grid challenges. In addition, knowing the main technologies involved in the
deployment of smart grids (SGs) is important to highlight possible
shortcomings that can be mitigated by developing new tools. This paper
contributes to the research trends mentioned above by focusing on two
objectives. First, a bibliometric analysis is presented to give an overview of
the current research level about smart grid deployment. Second, a survey of
the main technological approaches used for smart grid implementation and
their contributions are highlighted. To that effect, we searched the Web of
Science (WoS), and the Scopus databases. We obtained 5,663 documents
from WoS and 7,215 from Scopus on smart grid implementation or
deployment. With the extraction limitation in the Scopus database, 5,872 of
the 7,215 documents were extracted using a multi-step process. These two
datasets have been analyzed using a bibliometric tool called bibliometrix.
The main outputs are presented with some recommendations for future
research.
Use of analytical hierarchy process for selecting and prioritizing islanding ...IJECEIAES
One of the problems that are associated to power systems is islanding
condition, which must be rapidly and properly detected to prevent any
negative consequences on the system's protection, stability, and security.
This paper offers a thorough overview of several islanding detection
strategies, which are divided into two categories: classic approaches,
including local and remote approaches, and modern techniques, including
techniques based on signal processing and computational intelligence.
Additionally, each approach is compared and assessed based on several
factors, including implementation costs, non-detected zones, declining
power quality, and response times using the analytical hierarchy process
(AHP). The multi-criteria decision-making analysis shows that the overall
weight of passive methods (24.7%), active methods (7.8%), hybrid methods
(5.6%), remote methods (14.5%), signal processing-based methods (26.6%),
and computational intelligent-based methods (20.8%) based on the
comparison of all criteria together. Thus, it can be seen from the total weight
that hybrid approaches are the least suitable to be chosen, while signal
processing-based methods are the most appropriate islanding detection
method to be selected and implemented in power system with respect to the
aforementioned factors. Using Expert Choice software, the proposed
hierarchy model is studied and examined.
Enhancing of single-stage grid-connected photovoltaic system using fuzzy logi...IJECEIAES
The power generated by photovoltaic (PV) systems is influenced by
environmental factors. This variability hampers the control and utilization of
solar cells' peak output. In this study, a single-stage grid-connected PV
system is designed to enhance power quality. Our approach employs fuzzy
logic in the direct power control (DPC) of a three-phase voltage source
inverter (VSI), enabling seamless integration of the PV connected to the
grid. Additionally, a fuzzy logic-based maximum power point tracking
(MPPT) controller is adopted, which outperforms traditional methods like
incremental conductance (INC) in enhancing solar cell efficiency and
minimizing the response time. Moreover, the inverter's real-time active and
reactive power is directly managed to achieve a unity power factor (UPF).
The system's performance is assessed through MATLAB/Simulink
implementation, showing marked improvement over conventional methods,
particularly in steady-state and varying weather conditions. For solar
irradiances of 500 and 1,000 W/m2
, the results show that the proposed
method reduces the total harmonic distortion (THD) of the injected current
to the grid by approximately 46% and 38% compared to conventional
methods, respectively. Furthermore, we compare the simulation results with
IEEE standards to evaluate the system's grid compatibility.
Enhancing photovoltaic system maximum power point tracking with fuzzy logic-b...IJECEIAES
Photovoltaic systems have emerged as a promising energy resource that
caters to the future needs of society, owing to their renewable, inexhaustible,
and cost-free nature. The power output of these systems relies on solar cell
radiation and temperature. In order to mitigate the dependence on
atmospheric conditions and enhance power tracking, a conventional
approach has been improved by integrating various methods. To optimize
the generation of electricity from solar systems, the maximum power point
tracking (MPPT) technique is employed. To overcome limitations such as
steady-state voltage oscillations and improve transient response, two
traditional MPPT methods, namely fuzzy logic controller (FLC) and perturb
and observe (P&O), have been modified. This research paper aims to
simulate and validate the step size of the proposed modified P&O and FLC
techniques within the MPPT algorithm using MATLAB/Simulink for
efficient power tracking in photovoltaic systems.
Adaptive synchronous sliding control for a robot manipulator based on neural ...IJECEIAES
Robot manipulators have become important equipment in production lines, medical fields, and transportation. Improving the quality of trajectory tracking for
robot hands is always an attractive topic in the research community. This is a
challenging problem because robot manipulators are complex nonlinear systems
and are often subject to fluctuations in loads and external disturbances. This
article proposes an adaptive synchronous sliding control scheme to improve trajectory tracking performance for a robot manipulator. The proposed controller
ensures that the positions of the joints track the desired trajectory, synchronize
the errors, and significantly reduces chattering. First, the synchronous tracking
errors and synchronous sliding surfaces are presented. Second, the synchronous
tracking error dynamics are determined. Third, a robust adaptive control law is
designed,the unknown components of the model are estimated online by the neural network, and the parameters of the switching elements are selected by fuzzy
logic. The built algorithm ensures that the tracking and approximation errors
are ultimately uniformly bounded (UUB). Finally, the effectiveness of the constructed algorithm is demonstrated through simulation and experimental results.
Simulation and experimental results show that the proposed controller is effective with small synchronous tracking errors, and the chattering phenomenon is
significantly reduced.
Remote field-programmable gate array laboratory for signal acquisition and de...IJECEIAES
A remote laboratory utilizing field-programmable gate array (FPGA) technologies enhances students’ learning experience anywhere and anytime in embedded system design. Existing remote laboratories prioritize hardware access and visual feedback for observing board behavior after programming, neglecting comprehensive debugging tools to resolve errors that require internal signal acquisition. This paper proposes a novel remote embeddedsystem design approach targeting FPGA technologies that are fully interactive via a web-based platform. Our solution provides FPGA board access and debugging capabilities beyond the visual feedback provided by existing remote laboratories. We implemented a lab module that allows users to seamlessly incorporate into their FPGA design. The module minimizes hardware resource utilization while enabling the acquisition of a large number of data samples from the signal during the experiments by adaptively compressing the signal prior to data transmission. The results demonstrate an average compression ratio of 2.90 across three benchmark signals, indicating efficient signal acquisition and effective debugging and analysis. This method allows users to acquire more data samples than conventional methods. The proposed lab allows students to remotely test and debug their designs, bridging the gap between theory and practice in embedded system design.
Detecting and resolving feature envy through automated machine learning and m...IJECEIAES
Efficiently identifying and resolving code smells enhances software project quality. This paper presents a novel solution, utilizing automated machine learning (AutoML) techniques, to detect code smells and apply move method refactoring. By evaluating code metrics before and after refactoring, we assessed its impact on coupling, complexity, and cohesion. Key contributions of this research include a unique dataset for code smell classification and the development of models using AutoGluon for optimal performance. Furthermore, the study identifies the top 20 influential features in classifying feature envy, a well-known code smell, stemming from excessive reliance on external classes. We also explored how move method refactoring addresses feature envy, revealing reduced coupling and complexity, and improved cohesion, ultimately enhancing code quality. In summary, this research offers an empirical, data-driven approach, integrating AutoML and move method refactoring to optimize software project quality. Insights gained shed light on the benefits of refactoring on code quality and the significance of specific features in detecting feature envy. Future research can expand to explore additional refactoring techniques and a broader range of code metrics, advancing software engineering practices and standards.
Smart monitoring technique for solar cell systems using internet of things ba...IJECEIAES
Rapidly and remotely monitoring and receiving the solar cell systems status parameters, solar irradiance, temperature, and humidity, are critical issues in enhancement their efficiency. Hence, in the present article an improved smart prototype of internet of things (IoT) technique based on embedded system through NodeMCU ESP8266 (ESP-12E) was carried out experimentally. Three different regions at Egypt; Luxor, Cairo, and El-Beheira cities were chosen to study their solar irradiance profile, temperature, and humidity by the proposed IoT system. The monitoring data of solar irradiance, temperature, and humidity were live visualized directly by Ubidots through hypertext transfer protocol (HTTP) protocol. The measured solar power radiation in Luxor, Cairo, and El-Beheira ranged between 216-1000, 245-958, and 187-692 W/m 2 respectively during the solar day. The accuracy and rapidity of obtaining monitoring results using the proposed IoT system made it a strong candidate for application in monitoring solar cell systems. On the other hand, the obtained solar power radiation results of the three considered regions strongly candidate Luxor and Cairo as suitable places to build up a solar cells system station rather than El-Beheira.
An efficient security framework for intrusion detection and prevention in int...IJECEIAES
Over the past few years, the internet of things (IoT) has advanced to connect billions of smart devices to improve quality of life. However, anomalies or malicious intrusions pose several security loopholes, leading to performance degradation and threat to data security in IoT operations. Thereby, IoT security systems must keep an eye on and restrict unwanted events from occurring in the IoT network. Recently, various technical solutions based on machine learning (ML) models have been derived towards identifying and restricting unwanted events in IoT. However, most ML-based approaches are prone to miss-classification due to inappropriate feature selection. Additionally, most ML approaches applied to intrusion detection and prevention consider supervised learning, which requires a large amount of labeled data to be trained. Consequently, such complex datasets are impossible to source in a large network like IoT. To address this problem, this proposed study introduces an efficient learning mechanism to strengthen the IoT security aspects. The proposed algorithm incorporates supervised and unsupervised approaches to improve the learning models for intrusion detection and mitigation. Compared with the related works, the experimental outcome shows that the model performs well in a benchmark dataset. It accomplishes an improved detection accuracy of approximately 99.21%.
Tools & Techniques for Commissioning and Maintaining PV Systems W-Animations ...Transcat
Join us for this solutions-based webinar on the tools and techniques for commissioning and maintaining PV Systems. In this session, we'll review the process of building and maintaining a solar array, starting with installation and commissioning, then reviewing operations and maintenance of the system. This course will review insulation resistance testing, I-V curve testing, earth-bond continuity, ground resistance testing, performance tests, visual inspections, ground and arc fault testing procedures, and power quality analysis.
Fluke Solar Application Specialist Will White is presenting on this engaging topic:
Will has worked in the renewable energy industry since 2005, first as an installer for a small east coast solar integrator before adding sales, design, and project management to his skillset. In 2022, Will joined Fluke as a solar application specialist, where he supports their renewable energy testing equipment like IV-curve tracers, electrical meters, and thermal imaging cameras. Experienced in wind power, solar thermal, energy storage, and all scales of PV, Will has primarily focused on residential and small commercial systems. He is passionate about implementing high-quality, code-compliant installation techniques.
Impartiality as per ISO /IEC 17025:2017 StandardMuhammadJazib15
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Determination of Equivalent Circuit parameters and performance characteristic...pvpriya2
Includes the testing of induction motor to draw the circle diagram of induction motor with step wise procedure and calculation for the same. Also explains the working and application of Induction generator
Particle Swarm Optimization–Long Short-Term Memory based Channel Estimation w...IJCNCJournal
Paper Title
Particle Swarm Optimization–Long Short-Term Memory based Channel Estimation with Hybrid Beam Forming Power Transfer in WSN-IoT Applications
Authors
Reginald Jude Sixtus J and Tamilarasi Muthu, Puducherry Technological University, India
Abstract
Non-Orthogonal Multiple Access (NOMA) helps to overcome various difficulties in future technology wireless communications. NOMA, when utilized with millimeter wave multiple-input multiple-output (MIMO) systems, channel estimation becomes extremely difficult. For reaping the benefits of the NOMA and mm-Wave combination, effective channel estimation is required. In this paper, we propose an enhanced particle swarm optimization based long short-term memory estimator network (PSOLSTMEstNet), which is a neural network model that can be employed to forecast the bandwidth required in the mm-Wave MIMO network. The prime advantage of the LSTM is that it has the capability of dynamically adapting to the functioning pattern of fluctuating channel state. The LSTM stage with adaptive coding and modulation enhances the BER.PSO algorithm is employed to optimize input weights of LSTM network. The modified algorithm splits the power by channel condition of every single user. Participants will be first sorted into distinct groups depending upon respective channel conditions, using a hybrid beamforming approach. The network characteristics are fine-estimated using PSO-LSTMEstNet after a rough approximation of channels parameters derived from the received data.
Keywords
Signal to Noise Ratio (SNR), Bit Error Rate (BER), mm-Wave, MIMO, NOMA, deep learning, optimization.
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3rd International Conference on Artificial Intelligence Advances (AIAD 2024)GiselleginaGloria
3rd International Conference on Artificial Intelligence Advances (AIAD 2024) will act as a major forum for the presentation of innovative ideas, approaches, developments, and research projects in the area advanced Artificial Intelligence. It will also serve to facilitate the exchange of information between researchers and industry professionals to discuss the latest issues and advancement in the research area. Core areas of AI and advanced multi-disciplinary and its applications will be covered during the conferences.
Accident detection system project report.pdfKamal Acharya
The Rapid growth of technology and infrastructure has made our lives easier. The
advent of technology has also increased the traffic hazards and the road accidents take place
frequently which causes huge loss of life and property because of the poor emergency facilities.
Many lives could have been saved if emergency service could get accident information and
reach in time. Our project will provide an optimum solution to this draw back. A piezo electric
sensor can be used as a crash or rollover detector of the vehicle during and after a crash. With
signals from a piezo electric sensor, a severe accident can be recognized. According to this
project when a vehicle meets with an accident immediately piezo electric sensor will detect the
signal or if a car rolls over. Then with the help of GSM module and GPS module, the location
will be sent to the emergency contact. Then after conforming the location necessary action will
be taken. If the person meets with a small accident or if there is no serious threat to anyone’s
life, then the alert message can be terminated by the driver by a switch provided in order to
avoid wasting the valuable time of the medical rescue team.
We have designed & manufacture the Lubi Valves LBF series type of Butterfly Valves for General Utility Water applications as well as for HVAC applications.
Properties of Fluids, Fluid Statics, Pressure MeasurementIndrajeet sahu
Properties of Fluids: Density, viscosity, surface tension, compressibility, and specific gravity define fluid behavior.
Fluid Statics: Studies pressure, hydrostatic pressure, buoyancy, and fluid forces on surfaces.
Pressure at a Point: In a static fluid, the pressure at any point is the same in all directions. This is known as Pascal's principle. The pressure increases with depth due to the weight of the fluid above.
Hydrostatic Pressure: The pressure exerted by a fluid at rest due to the force of gravity. It can be calculated using the formula P=ρghP=ρgh, where PP is the pressure, ρρ is the fluid density, gg is the acceleration due to gravity, and hh is the height of the fluid column above the point in question.
Buoyancy: The upward force exerted by a fluid on a submerged or partially submerged object. This force is equal to the weight of the fluid displaced by the object, as described by Archimedes' principle. Buoyancy explains why objects float or sink in fluids.
Fluid Pressure on Surfaces: The analysis of pressure forces on surfaces submerged in fluids. This includes calculating the total force and the center of pressure, which is the point where the resultant pressure force acts.
Pressure Measurement: Manometers, barometers, pressure gauges, and differential pressure transducers measure fluid pressure.
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safe guarding are must for Dual polarization QAM [14]. In situations where optical channels are impaired by
amplified spontaneous emission (ASE) noises, the error vector magnitude (EVM) and the optical signal to
noise ratio (OSNR) play a pivotal role in measuring the performance of those optical channels [2, 5].
By the same token, it is very much important to portray optical I-Q transmitters [15]. Still now,
the interaction of BER and OSNR with respect to EVM is not well ascertained in COTS [16]. Moreover,
EVM is better metric than BER when symbol sequences are unknown. Thereby association between EVM
and BER are highly momentous for COTS [15]. In this paper the effect of nonlinear distortion on DP-QAM
based COTS was analyzed in Optisystem software environment. In case of QAM, information encoding is
done on amplitude and phase which required very sophisticated analysis and quantization technique
to measure the efficiency of COTS [17]. EVM and OSNR are widely applied parameters for
evaluating the performance of COTS where the optical channels are adversely affected by ASE noise and
I-Q transmitters [17].
With the help of EVM we can calculate the deviation of actual received data from the expected
value of demodulated data [18]. But signal-to-noise ratio (SNR), EVM and BER originally derived wireless
digital communications which are not compatible with optical communications systems [5]. Proper algorithm
of COTS is necessary for accurately validating the interdependency between EVM and BER [17, 19].
The prime parameters that were analyzed here are Input transmitting power, propagation optical length,
EVM, BER and OSNR. Proper investigation of EVM is an inevitable which necessitates the derivation of
an analytical closed form expression for EVM [20]. In addition to that simulated outputs of the constellation
diagrams for x polarization and y polarization were found in accordance to our findings. We derived a novel
expression presenting the relationships among EVM, OSNR and BER for the designed transmitter receiver of
the COTS. Then we designed the algorithm for simulation flow representing the complete simulated COTS
architecture. We presented our simulation results along with comparison table containing the existing works
and thereby validation of our findings from the simulated COTS is shown. This paper is decorated as follows:
In Section 1, in the introduction part we provided background with literature review, the problem statement
and our novel analytical expression where the interaction among BER, OSNR and EVM are presented
mathematically. In Section 2, analytical analysis of the work is presented. In Section 3 describes
the simulation layout of the systems. In Section 4, we incorporated the results and findings. Conclusion of
the paper and future directions are provided in Section 5.
2. ANALYTICAL ANALYSIS
EVM is the measurement of the difference between reference signal and received signal.
Consequently, magnitude error, vector error and phase error produced between the transmitted symbols and
received symbols in COTS. The mathematical expression [3, 21] to determine the EVM of the COTS
is as follows
D
nSnS
N
EVM
N
n
rt
1
2
)()(
1
(1)
where, N is the total number of transmitted bits, St (n) is the function of reference transmitted bits, Sr (n) is
the function of received bits in the systems and D is the operator which maximize the magnitude (Rmax) or
either maximize the normalized or average bit power (P0) for all transmitted bits for the preferred modulation
levels. As a result, EVM is inversely proportional to the signal to noise ratio (SNR) [22]. OSNR is equal to
the multiplication of SNR with bit rate (Rs) when the result of multiplication is divided by the reference
optical bandwidth (Bref) [2]. The following formula [3, 16, 23, 24] is to measure the bit error rate for
the EVM which is expressed below in the (2)
MR
BOSNR
L
L
kerfc
L
L
BER
s
ref
2
2
21
2
1
log
)()(2
)1(
log3
log
)1(
(2)
In (2), Rs represents the bit rate. Bref is the reference optical bandwidth. L and M are the bit levels
and constellation points number of the desired modulation levels respectively. In this way, for DP-32QAM,
DP-64QAM and DP-128QAM formats, L and M produce the 5, 6, 7 bits and 32, 64 and 128 constellation
points respectively. OSNR is the optical signal to noise ratio. k is the ratio of received and typical
constellation points in COTS for DP-QAM levels.
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3. SIMULATION LAYOUT
Figures 1, 2, 3 and Figures 4(a), 4(b) represent [3, 11, 25, 26] the block diagram of COTS, algorithm
of simulation flow for DP-QAM based COTS, architecture test bed of COTS, layout of coherent QAM
square DP transmitter and receiver of COTS respectively. The system consists of coherent QAM square DP
transmitter; optical link and coherent QAM square DP Receiver. The optical link section consists of optical
fiber and EDFA. Data rate of 100 Gb/s is considered to simulate the test bed of COTS with DP-QAM in
Optisystem optical simulation software tool. In this scenario, coherent QAM square DP transmitter transmits
at the wavelength of 193.1 THz for various DP-QAM levels. Then the transmitted signal is separated in
X and Y components. Consequently, the outputs go through the I-Q modulator and thereby yield DP-QAM
signals. Now the modulating DP-QAM signals passed through the optical amplifier. The amplified signal
passed through the optical link with 80km span length considering single mode fiber (SMF).
To compensate the fiber attenuation and nonlinearities of the SMF, the optical amplifier used in
the link. At the receiver section, coherent QAM square DP receiver is employed to detect the optical signal.
In receiver module PBS (Polarization Beam splitter) creates two reciprocally polarized signals.
For the detection of four optical fields there are four photodiodes are used to convert the optical signal to
electrical signal. After that the electrical signal is passed through the analog to digital converter (ADC) to get
the digital signals. Eventually DSP processor module used in the simulation for minimization of frequency
and phase differences that occur in the COTS which is then go through the threshold based circuitry.
Afterward bit error rate test tool is used to assess the BER performance of COTS for DP-QAM levels.
Figure 1. Schematic block diagram of simulation setup for COTS
Figure 2. Algorithm of simulation flow for DP-QAM based COTS, where PBS-polarization beam splitter,
MZM- mach-zehnder modulator, OA- optical amplifier, PIN-p-i-n photodiode
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Figure 3. Architecture of test bed COTS
(a)
Figure 4. (a) Optisystem layout of coherent QAM square DP transmitter,
(b) Optisystem layout of coherent QAM square DP receiver
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4. RESULTS
Global parameters for the system are data rate of 100Gb/s, dual polarization, square constellation
types, 65536 number of samples which are used to simulate the COTS. As a result the symbol rate for
DP-32QAM, DP-64QAM and DP-128QAM are 10 Gsymbol/s, 8.33 Gsymbol/s and 7.142 Gsymbol/s
respectively. The operating channel wave length is 193.1THz. The operating input power for CW Laser
is -20dBm to 5dBm. The operating Optical Signal to Noise Ratio (OSNR) is 12 to 30 dB. The fiber link is of
80 km span length. The fiber attenuation is 0.2dB/km. The fiber dispersion coefficient is 16ps/nm-km.
The gain of EDFA is 16dB and the noise figure is 4dB. Fiber Nonlinearities is 26e-021
m2
/w and fiber effective
area is 80e-012
. Following the systematic procedure and test bed of COTS, we have found the following
results. Figure 5 represents the optical modulating signal displays in Optical Spectrum Analyser (OSA)
before sending through the optical link. After the DP-QAM the input message signal as shown in Figure 5,
is transmitted through the optical Channel. In the receiver module the downlink receiver is used to
demodulate the received signal which was transmitted through the optical channel. And it is splitted in
electrical form to the in channel and quadrature channel parts.
Figure 5. Input power versus frequency of CW laser
Figure 6 represents the comparison for input power (dBm) for DP-QAM level schemes in terms of
EVM (%). In Figure 6, it is found that the propagation efficiency is examined by changing the CW input
power to observe the corresponding impact of CW input power on Error vector magnitude(%) for
the distance of back to back (B2B), 80 km and 400 km after reimbursement for the dispersion effect of
the optical propagation system. In this setup the EVM is calculated in case of DP-32QAM, DP-64QAM, and
DP-128QAM. The setup reveals that EVM figure for various modulation techniques has an inclination to
down fall behavior against CW input power. At -9dBm, there is an unusual phenomenon that the linearity of
the output graphs tends to more down wards. At input power -9 dBm, DP-128QAM shows the EVM of 9.5%,
9.6%, and 10.7% where DP-64QAM exhibits the EVM of 12.24%, 13.3% and 15.1% and lastly DP-32QAM
provides the EVM of 17.45%, 19.23% and 22.34% for back to back, 1 span and 5 spans respectively.
Figure 7 exposes the behavior of EVM with respect to propagation length at CW input powers of
0 dBm and 5 dBm in case of DP-32QAM, DP-64QAM, and DP-128QAM. It is observed from the figure that
EVM increases with the increment of the distance. At 100 km to 220 km, among all of the modulation
formats considered here in this setup, 0 dBm provides higher EVM as compared to 5dBm. At 220km to 600
km, DP-64QAM shows higher EVM for 5dBm as compared to 0dBm. On the other hand, DP-32QAM and
DP-128QAM both provides higher EVM in case of 0dBm as compared to 5dBm. And at 600 to 1200km
point it reaches to the pick point in case of input power of 0dBm and 5dBm. It is interesting to observe
that DP-32QAM, DP-64QAM, both shows almost similar behavioral patterns for 0dBm and 5dBm.
On the contrary, DP-128QAM provides more %EVM for 5dBm input power where it shows lesser EVM
for 0dBm.
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Figure 6. Performance comparison for input power (dBm) for DP-QAM level schemes in terms of EVM (%)
Figure 7. Propagation length (km) versus error vector magnitude (%)
Figure 8 reveals the BER performance with respect to the OSNR. This graph of figure exposes that
DP-128QAM 5 spans, DP-128QAM b2b and DP-128QAM 1 span are not suitable for error free transmission
at the simulated OSNR range. Besides, DP-32QAM B2B, DP-64QAM B2B gives lower BER which is
compatible with our basic prediction. But DP-128QAM b2b has deviated from normal behavior, thereby not
supporting acceptable BER performance. On the contrary, DP-32QAM 1 span provides very virtuous BER
performance. We have observed that similar better output are obtained for DP-32QAM 1 span and
DP-64QAM 1 span. Although, DP-32QAM 5 span and DP-64QAM 5 spans yields worse performance which
is not acceptable for error free communications. These observations are also confirmed by the constellation
point evidences shown in Table 1. Table 2 represents the comparison among related works. It validates that
our design performs better in terms of OSNR than previous works. Our investigation shows the maximum
OSNR of 28dB at DP-32QAM level compared to existing works in Table 2.
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Figure 8. Performance comparison for DP- QAM levels with respect to OSNR versus log of BER
Table 1. Constellations diagrams of DP-QAM levels for COTS performance comparison
DP-QAM Levels Back to Back Propogation Propagation for 80 km ( 1 Span)
DP-32QAM
(X Polarization)
DP-32QAM
(Y Polarization)
DP-64QAM
(X Polarization)
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Table 1. Constellations diagrams of DP-QAM levels for COTS performance comparison (continue)
DP-QAM Levels Back to Back Propogation Propagation for 80 km ( 1 Span)
DP-64QAM
(Y Polarization)
DP-128QAM
(X Polarization)
DP-128QAM
(Y Polarization)
Table 2. Comparison table of our work with previous works
Factors Ref. No. [3] Ref. No. [8] Ref. No. [11] Ref. No. [13] Current
Investigation
Technology Coherent Optical
Systems
Coherent Optical
Systems
Coherent Optical
Systems
Coherent
detection
Coherent Optical
Systems
Modulation Formats Advanced Advanced M-QAM Advanced M-QAM
Data Rate(Gbps) 112 904 400 256 100
Channel Input power(dBm) -20 to 5 0 -------- -3 to 3 -20 to 5
Wavelength/ frequency 193.1THz 1550 nm -------- 1557.36nm 193.1 THz
Fiber attenuation(dB/km) 0.2 0.2 -------- -------- 0.2
Span length(km) 80 80 -------- 75 80
Dispersion
(ps/nm/km)
16 16.75 -------- -------- 16
Polarization Type Dual Dual PM SP and Dual Dual
Modulation signal level 32QAM 128QAM 32QAM and
64QAM
128QAM and
16QAM
32QAM
Amplifier EDFA EDFA EDFA EDFA
Amplifier Gain (dB) 16 16 -------- -------- 16
Noise Figure(dB) 4 4 -------- -------- 4
OSNR(dB) 23.5 27 21.8 and 24.3 18 and 19 28
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5. CONCLUSION
We exhibited the COTS with multiple types of DP-QAM levels. The performance of
the DP-32QAM, DP-64QAM and DP-128QAM modulation formats with the same data rate (100Gb/s) and
different symbol rates (10 Gsymbol/s, 8.33 Gsymbol/s and 7.142 Gsymbol/s respectively) have been
compared in terms of CW input power. The findings based on the performance curves and constellation
diagrams are in harmony with the analytical manifestation and are strong evidences to our explanation of
the outputs.
This simulation work helps the calculation of EVM with respect to propagation length, input
channel power for DP-QAM levels. It is interesting that for the same test bed of COTS, three DP- QAM
levels performed differently. This investigation improves the optical transmission systems by minimizing
the error vector magnitude (EVM). In this simulation, it is found that DP-128QAM outperforms DP-32QAM
and DP-64QAM. DP-128QAM has a potentiality to rescue from the detrimental factors that arises from long
haul optical fiber communications link.
ACKNOWLEDGEMENTS
The authors are thankful to University Grants Commission of Bangladesh (UGC) for sponsoring this
research work under the research scheme grant, 2017.
REFERENCES
[1] Yuki Koizumi, et al., “1024 QAM (60 Gbit/s) single carrier coherent optical transmission over 150 km,” Optics
Express, vol. 20, no. 11, May 2012.
[2] Xiaosheng Xiao, et al., “Influence of ASE noise on the signal OSNR and error vector magnitude in coherent optical
communications,” Optoelectronics Global Conference, Aug. 2015.
[3] Monika Mehra, et al., “Performance Analysis of Coherent Optical Communication System for Higher order Dual
Polarization Modulation Formats,” Optik- International Journal for Light and Electron Optics, vol. 135,
pp. 174-179, Apr. 2017.
[4] Peter J. Winzer, “High-Spectral-Efficiency Optical Modulation Formats,” Journal of Lightwave Technology,
vol. 30, no. 24, pp. 3824-3835, 2012.
[5] Huaqiang Qin, et al., “Modeling of the Impacts of Nonlinear Propagation on EVM for Digital Coherent Receivers,”
16th International Conference on Optical Communications and Networks (ICOCN), Aug. 2017.
[6] Z. Dong, et al., “OSNR monitoring for QPSK and 16-QAM systems in presence of fiber nonlinearities for digital
coherent receivers,” Optics express, vol. 20, pp. 19520-19534, 2012.
[7] A. Carena, et al., “Statistical characterization of PM-QPSK signals after propagation in uncompensated fiber links,”
in Proc. ECOC, 2010.
[8] Guang Li, et al., “A Pulse Shaping Based Optical Transmission System of 128QAM for DWDM with N × 904
Gbps,” Applied Sciences, vol. 9, no. 5, pp. 988, Mar. 2019.
[9] Seiji Okamoto, et al., “512 QAM (54 Gbit/s) coherent optical transmission over 150 km with an optical bandwidth
of 4.1 GHz,” 36th
European Conference and Exhibition on Optical Communication (ECOC), Sep. 2010.
[10] Júlio César Medeiros Diniz, et al., “Optimization of DP-M-QAM Transmitter Using Cooperative Coevolutionary
Genetic Algorithm,” Journal of Lightwave Technology, vol. 36, no. 12, Jun. 2018.
[11] E. Lach, et al., “Modulation formats for 100 G and beyond,” Optical Fiber Technology, vol. 17, no. 5,
pp. 377-386, 2011.
[12] B. Szafraniec, et al., “Performance monitoring and measurement techniques for coherent optical systems,” Journal
of Lightwave Technology, vol. 31, pp. 648–663, Feb. 2013.
[13] A. S. Kashi, et al., “Information Rates for the SP 128-QAM and DP 16-QAM Modulation Formats,” European
Conference on Optical Communication (ECOC), Oct. 2015.
[14] L. Alberto Campos, et al., “Proactive Network Maintenance Evolution to the Optical Domain in Coherent Optics,”
Advancing Technology's Agenda, Atlanta, GA, Oct. 2018.
[15] Martin Hudliˇcka, et al., “BER Estimation from EVM for QPSK and16-QAM Coherent Optical Systems,” IEEE 6th
International Conference on Photonics (ICP), Mar. 2016.
[16] Rene Schmogrow, et al., “Error Vector Magnitude as a Performance Measure for Advanced Modulation Formats,”
IEEE Photonics Technology Letters, vol. 24, pp. 61-63, Jan. 2012.
[17] I. Fatadin, "Estimation of BER from Error Vector Magnitude for Optical Coherent Systems,” Photonics, vol. 3,
no. 2, pp. 21, 2016.
[18] Maoliu Lin, et al., “EVM Simulation and its Comparison with BER for Different Types of Modulation,” TENCON,
Nov. 2007.
[19] Qinghua Yu, et al., “Research on Evaluation of BER in Communication system,” 15th
International Conference on
Optical Communications and Networks, Sep. 2016.
[20] A. Georgiadis, et al., "Evaluation of error vector magnitude due to combined IQ imbalances and phase noise,”
IET Circuits, Devices & Systems, vol. 8, no. 6, pp. 421-426, 2014.
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[21] Ruijiao Zhang, et al., “Full-duplex fiber-wireless link for alternative wired and 40-GHz band wireless access based
on differential quaternary phase-shift optical single sideband millimeter-wave signal,” Optical Engineering, vol. 54,
Feb. 2015.
[22] Rishad Ahmed Shafik, et al., “On the Extended Relationships among EVM, BER and SNR as Performance
Metrics,” ICECE, 2006.
[23] Chien-Yu Lin, “Digital Nonlinear Compensation for Next-Generation Optical Communication Systems Using
Advanced Modulation Formats,” Ph.D dissertation, Faculty of Engineering, Friedrich-Alexander-Universität
Erlangen-Nürnberg, Jan. 2014. [Online], Available: https://d-nb.info/1054331367/34.
[24] By Rene´-Jean Essiambre, et al., “Capacity Trends and Limits of Optical Communication Networks,” Proceedings
of the IEEE, vol. 100, no. 5, May 2012.
[25] [Online], Available: https://optiwave.com.
[26] Vipanpreet Kaur, et al., “A Study of Different Forms of Dual Polarization–Quadrature Amplitude Modulation and
its Performance Analysis in Terms of Q-Factor and Distance,” Journal of Optical Communications, Sep. 2018.