Filter Bank Multicarrier (FBMC) is a new waveform candidate in the visible light communication system (VLC). FBMC is a distinctive kind of multi-carrier modulation that can be regarded as an alternative to orthogonal frequency Division Multicarrier (OFDM) with CP (cyclic prefix). DCOFBMC (DC-bias optical FBMC) has recently been used in VLC, because it overcomes all defects in the optical-OFDM system and has high spectral efficiency. But at the same time the traditional DCO-FBMC suffers from high complexity due to the use of Hermitian Symmetry for real signal, by using 2Npoint subcarrier IFFT (Inverse Fast Fourier Transformer) in the modulator, and the output is N-point subcarrier FFT (Fast Fourier Transform) in the demodulator. In this paper, for the first time, the possibility of minimizing complexity and generating a real signal without the use of Hermitian Symmetry or any other technique has been verified. The proposed technology provides 50% of the size of the IFFT / FFT and this results in a significant reduction in power consumption and occupied chip area.
Performance evaluation on the basis of bit error rate for different order of ...ijmnct
This document summarizes research evaluating the bit error rate (BER) for different modulation orders and subchannel lengths in an orthogonal frequency division multiplexing (OFDM) system. The research considers QPSK, 8-QAM, and 16-QAM modulation with 256, 512, and 4096 subchannels. Simulation results in MATLAB show that:
1) For 256 subchannels, QPSK modulation has the lowest BER across signal-to-noise ratio (SNR) values from 0-27dB.
2) BER increases with higher modulation orders (from QPSK to 16-QAM) for a given subchannel length.
3) The research provides a comparative analysis of BER performance in an OFDM system
Performance Analysis of MIMO-OFDM System Using QOSTBC Code Structure for M-PSKCSCJournals
This document discusses performance analysis of MIMO-OFDM systems using QOSTBC coding for M-PSK modulation. It proposes a QOSTBC code structure for a 4x4 antenna configuration MIMO-OFDM system. It analyzes the performance of the system in AWGN and Rayleigh channels by evaluating BER versus SNR for different M-PSK modulation schemes and antenna configurations. The proposed MIMO-OFDM system with 4x4 QOSTBC coding is shown to have better performance than other systems in terms of lower BER for a given SNR.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
This document provides an overview of OFDM and the downlink physical layer design in LTE. It discusses why OFDM is necessary for high data rates in LTE, describing how OFDM avoids intersymbol interference through the use of multiple orthogonal subcarriers. It then covers OFDM signal structure and modulation, including the transmitter and receiver designs based on the inverse discrete Fourier transform and discrete Fourier transform. The document also introduces the concept of a guard interval to eliminate intersymbol interference and provides a matrix representation of multicarrier systems using cyclic prefix and DFT/IDFT.
Simulation of ofdm modulation adapted to the transmission of a fixed imageIAEME Publication
This document summarizes a study on using OFDM modulation adapted for transmitting a fixed image over a disturbed channel. OFDM modulation was simulated using MATLAB. Both classic OFDM with a 25% guard interval and modified OFDM with a reduced guard interval below 25% were evaluated. Results were presented for various M-PSK modulation formats including BPSK, QPSK, 16PSK and 256PSK. Convolutional coding was also used to improve transmission quality. The performance of the system was evaluated in terms of the visual quality of the received image and parameters like SNR, BER under different modulation schemes and guard interval durations. Transmission of up to 98% of the original image quality was achieved.
Pwm technique to overcome the effect ofIJCNCJournal
Many current communication systems suffer from performance degradation due to the high sensitivity to
high power peaks especially in the nonlinear devices. The author introduces a new concept based on the
Pulse Width Modulation (PWM), namely MIMO-OFDM system based PWM (MO-PWM) to overcome this
deficiency. Here, the peak-to-average power ratio (PAPR) problem in Orthogonal Frequency Division
Multiplexing (OFDM) technique is used as a criterion to check the validity of the proposed work.
Moreover, the proposed system work has been implemented over Field Programmable Gate Array (FPGA),
which is designed to characterize both of the complexity and the speed issues.
The systems performance based MO-PWM and validity have been checked based on a numerical analysis
and a conducted simulation. The simulation results show that the MO-PWM can clearly reduce the PAPR
values nevertheless the used OFDM systems’ specifications, and gives a promising results over some
techniques found in the literature, such as clipping, SLM and PTS under same bandwidth occupancy and
system’s specifications.
This document is a lab report describing frequency modulation and detection using MATLAB. It includes:
1) Frequency modulating a carrier signal with a message signal in MATLAB and plotting the modulated signal in time and frequency domains using different modulation indexes to demonstrate narrowband, wideband, and carrier-dropped scenarios.
2) Using Simulink to frequency modulate a square wave message onto a carrier signal with a VCO and partially demodulating using slope detection.
3) Generating white noise in MATLAB, plotting it in time and frequency domains, and finding its autocorrelation function.
The document proposes a novel method to characterize nonlinear channels in OFDM systems using spectral notch signals. The method involves transmitting OFDM frames with and without spectral notches and analyzing the difference signal. This allows the estimation of frequency-domain Volterra kernels to be decomposed into independent subtasks involving fewer coefficients, improving accuracy and reducing complexity compared to conventional methods. Simulations validate that the proposed method has lower computational complexity than existing approaches for estimating kernels of cubically nonlinear channels in real baseband OFDM systems.
Performance evaluation on the basis of bit error rate for different order of ...ijmnct
This document summarizes research evaluating the bit error rate (BER) for different modulation orders and subchannel lengths in an orthogonal frequency division multiplexing (OFDM) system. The research considers QPSK, 8-QAM, and 16-QAM modulation with 256, 512, and 4096 subchannels. Simulation results in MATLAB show that:
1) For 256 subchannels, QPSK modulation has the lowest BER across signal-to-noise ratio (SNR) values from 0-27dB.
2) BER increases with higher modulation orders (from QPSK to 16-QAM) for a given subchannel length.
3) The research provides a comparative analysis of BER performance in an OFDM system
Performance Analysis of MIMO-OFDM System Using QOSTBC Code Structure for M-PSKCSCJournals
This document discusses performance analysis of MIMO-OFDM systems using QOSTBC coding for M-PSK modulation. It proposes a QOSTBC code structure for a 4x4 antenna configuration MIMO-OFDM system. It analyzes the performance of the system in AWGN and Rayleigh channels by evaluating BER versus SNR for different M-PSK modulation schemes and antenna configurations. The proposed MIMO-OFDM system with 4x4 QOSTBC coding is shown to have better performance than other systems in terms of lower BER for a given SNR.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
This document provides an overview of OFDM and the downlink physical layer design in LTE. It discusses why OFDM is necessary for high data rates in LTE, describing how OFDM avoids intersymbol interference through the use of multiple orthogonal subcarriers. It then covers OFDM signal structure and modulation, including the transmitter and receiver designs based on the inverse discrete Fourier transform and discrete Fourier transform. The document also introduces the concept of a guard interval to eliminate intersymbol interference and provides a matrix representation of multicarrier systems using cyclic prefix and DFT/IDFT.
Simulation of ofdm modulation adapted to the transmission of a fixed imageIAEME Publication
This document summarizes a study on using OFDM modulation adapted for transmitting a fixed image over a disturbed channel. OFDM modulation was simulated using MATLAB. Both classic OFDM with a 25% guard interval and modified OFDM with a reduced guard interval below 25% were evaluated. Results were presented for various M-PSK modulation formats including BPSK, QPSK, 16PSK and 256PSK. Convolutional coding was also used to improve transmission quality. The performance of the system was evaluated in terms of the visual quality of the received image and parameters like SNR, BER under different modulation schemes and guard interval durations. Transmission of up to 98% of the original image quality was achieved.
Pwm technique to overcome the effect ofIJCNCJournal
Many current communication systems suffer from performance degradation due to the high sensitivity to
high power peaks especially in the nonlinear devices. The author introduces a new concept based on the
Pulse Width Modulation (PWM), namely MIMO-OFDM system based PWM (MO-PWM) to overcome this
deficiency. Here, the peak-to-average power ratio (PAPR) problem in Orthogonal Frequency Division
Multiplexing (OFDM) technique is used as a criterion to check the validity of the proposed work.
Moreover, the proposed system work has been implemented over Field Programmable Gate Array (FPGA),
which is designed to characterize both of the complexity and the speed issues.
The systems performance based MO-PWM and validity have been checked based on a numerical analysis
and a conducted simulation. The simulation results show that the MO-PWM can clearly reduce the PAPR
values nevertheless the used OFDM systems’ specifications, and gives a promising results over some
techniques found in the literature, such as clipping, SLM and PTS under same bandwidth occupancy and
system’s specifications.
This document is a lab report describing frequency modulation and detection using MATLAB. It includes:
1) Frequency modulating a carrier signal with a message signal in MATLAB and plotting the modulated signal in time and frequency domains using different modulation indexes to demonstrate narrowband, wideband, and carrier-dropped scenarios.
2) Using Simulink to frequency modulate a square wave message onto a carrier signal with a VCO and partially demodulating using slope detection.
3) Generating white noise in MATLAB, plotting it in time and frequency domains, and finding its autocorrelation function.
The document proposes a novel method to characterize nonlinear channels in OFDM systems using spectral notch signals. The method involves transmitting OFDM frames with and without spectral notches and analyzing the difference signal. This allows the estimation of frequency-domain Volterra kernels to be decomposed into independent subtasks involving fewer coefficients, improving accuracy and reducing complexity compared to conventional methods. Simulations validate that the proposed method has lower computational complexity than existing approaches for estimating kernels of cubically nonlinear channels in real baseband OFDM systems.
Multi carrier equalization by restoration of redundanc y (merry) for adaptive...IJNSA Journal
This paper proposes a new blind adaptive channel shortening approach for multi-carrier systems. The
performance of the discrete Fourier transform-DMT (DFT-DMT) system is investigated with the proposed
DST-DMT system over the standard carrier serving area (CSA) loop1. Enhanced bit rates demonstrated
and less complexity also involved by the simulation of the DST-DMT system.
PAPR REDUCTION OF OFDM SIGNAL BY USING COMBINED HADAMARD AND MODIFIED MEU-LAW...IJCNCJournal
Orthogonal frequency division multiplexing (OFDM) is a technique which gives high quality of service (QOS) to the users by mitigating the fading signals as well as high data rates in multimedia services. However, the peak-to-average power ratio (PAPR) is a technical challenge that reduces the efficiency of RF power amplifiers. In this paper, we propose the combined Hadamard transform and modified meu-law companding transform method in order to lessen the effects of the peak-to-average power ratio of the
OFDM signal. Simulation results show that the proposed scheme reduces PAPR compared to other companding techniques as well as the Hadamard transform technique when used on its own.
IRJET- Survey Paper on Paper Reduction for MIMO-OFDM Systems using PTS SchemeIRJET Journal
This document summarizes research on techniques to reduce peak-to-average power ratio (PAPR) in MIMO-OFDM systems. It discusses how PAPR significantly affects OFDM and can cause nonlinearity in high power amplifiers. The paper focuses on using partial transmit sequence techniques to reduce PAPR. It reviews related work applying techniques like iterative clipping and filtering, partial transmit sequences, and adaptive selected mapping to reduce PAPR. The document also discusses system models for MIMO-OFDM and analyzing PAPR reduction performance.
Design of Simulink Model for Constant Envelop OFDM & Analysis of Bit Error RateIJSRD
This paper describes a transformation technique aimed at solving the peak-to-average power ratio (PAPR) problem associated with OFDM (Orthogonal Frequency Division Multiplexing). The Constant Envelop-OFDM solves the problem of high peak-to-average power ratio (PAPR) in OFDM, reducing PAPR to 0 dB. The constant envelope signal can be efficiently amplified with nonlinear power amplifiers thus achieving greater power efficiency. It is shown that CE-OFDM’s performance is better than conventional OFDM when taking into account the effects of the power amplifier. The performance of CE-OFDM is analyzed in additive white Gaussian noise (AWGN) channel. CE-OFDM is shown to achieve good performance with the use of cyclic prefix transmission. By way of computer simulation, CE-OFDM is shown to compare favorably to conventional OFDM. OFDM and CE-OFDM is analyzed on grounds of BER with additive white Gaussian noise (AWGN). The BER is calculated and the performance of OFDM and CE OFDM is compared.
Orthogonal Frequency Division Multiplexing with Offset Quadrature Amplitude Modulation
(OFDM / OQAM) is a multicarrier modulation scheme that can be considered as an alternative
to the conventional Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix
(CP) for transmission over multipath fading channels. In this paper, we investigate the
combination of the OFDM/OQAM with Alamouti system with Time Reversal (TR) technique.
TR can be viewed as a precoding scheme which can be combined with OFDM/OQAM and
easily carried out in a Multiple Input Single Output (MISO) context such as Alamouti system.
We present the simulation results of the performance of OFDM/OQAM system in SISO case
compared with the conventional CP-OFDM system and the performance of the combination
Alamouti OFDM / OQAM with TR compared to Alamouti CP-OFDM. The performance is
derived by computing the Bit Error Rate (BER) as a function of the transmit signal-to-noise
ratio (SNR).
Spatial multiplexing ofdmoqam systems with time reversal techniqueijwmn
Orthogonal Frequency Division Multiplexing with Offset Quadrature Amplitude Modulation (OFDM/OQAM) is a multicarrier modulation scheme that can be considered as an alternative to the conventional Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix (CP) for transmission over multipath fading channels. In this paper, we investigate the combination of the OFDM/OQAM with Multiple Input Multiple Output (MIMO) system with Time Reversal (TR) technique.
TR can be viewed as a precoding scheme which can be combined with OFDM/OQAM and easily carried out in a MIMO context using spatial data multiplexing.
We present the simulation results of the performance of OFDM/OQAM system in SISO case compared with the conventional CP-OFDM system and the performance of the combination MIMO-OFDM/OQAM with TR compared to MIMO-CP-OFDM. The performance is derived by computing the Bit Error Rate (BER) as a function of the transmit signal-to-noise ratio (SNR).
This document summarizes a research paper that evaluates the performance of different MIMO techniques for MIMO-OFDM systems. It describes spatial multiplexing (SM), space time block coding (STBC), and a hybrid model combining SM and STBC. A simulation model of a 4x4 antenna hybrid MIMO-OFDM system is developed. Results show the hybrid system provides lower bit error rates than SM or STBC systems alone, improving both data rate and link reliability for wireless communication.
Phydyas 09 fFilter Bank Multicarrier (FBMC): An Integrated Solution to Spectr...Marwan Hammouda
The document discusses filter bank multicarrier (FBMC) as a solution for spectrum sensing and data transmission in cognitive radio networks. Conventional OFDM has limitations for these tasks due to its sidelobe leakage, which causes interference between primary and secondary users. FBMC uses a filter bank approach instead of FFT to provide better frequency localization and reduce sidelobe leakage without reducing bandwidth efficiency. The document outlines the benefits of FBMC over OFDM for spectrum sensing and sharing in cognitive radio.
An Adaptive Approach to Switching Coded Modulation in OFDM System Under AWGN ...ijsrd.com
In this paper we have studied the OFDM for different Quadrature amplitude modulation technique (QAM) The scatter plot and their output signal to noise ratio, dependent bit error rate variation is analyzed for every type of modulation in OFDM. After observing the BER for each SNR in the system, switching threshold range has been prepared and now system is ready to face the Adaptive coded modulation (ACM).The results shows the switching of modulation technique.
The International Journal of Engineering and Science (The IJES)theijes
1. The document proposes an efficient method for inter-carrier interference (ICI) cancellation and peak-to-average power ratio (PAPR) reduction in MIMO-OFDM wireless systems.
2. It develops an expectation-maximization algorithm to jointly estimate carrier frequency offset and channel impulse response. It also designs a minimum mean-square error precoding matrix to reduce PAPR.
3. The key contribution is a progressive parallel inter-carrier interference canceller based on factor graphs. It iteratively reconstructs and cancels ICI across subcarriers in both the frequency and space domains to improve performance.
This document summarizes a research paper that proposes a modified channel shortener filter (MCSF) to improve the spectral efficiency of OFDM systems. The MCSF exploits the null space of an underdetermined system of equations to provide multiple independent equivalent channels to the receiver. It is shown that the MCSF can achieve a higher spectral efficiency than conventional OFDM when the cyclic prefix length is significantly smaller than the channel delay spread. Simulation results demonstrate that the MCSF improves bit error rate performance and can provide up to 2dB gain compared to full cyclic prefix OFDM systems. The MCSF has the potential to reduce receiver complexity compared to existing channel shortening approaches.
Implementation and Study of Universal Filtered Multi Carrier under Carrier Fr...Editor IJAIEM
Sathiyapriya N.S
PG Student, Dept. of ECE, Periyar Maniammai University Thanjavur, Tamilnadu, India
ABSTRACT
OFDM is a matured technology and applied in various wireless standards. However they are not suitable for Uplink and this
technology is replaced by SC FDMA in 4G standards. Similarly Universal Filtered Multicarrier Communication (UFMC) is
another suitable technology for Multi user Uplink and for applications like cognitive radio. UFMC is a new, non-orthogonal,
waveform designed by Alcatel Lucent Labs which provide a much more efficient way of enabling networks to serve both
broadband users and very narrowband “short data” devices such as any embedded sensor or M2M module. In UFMC the
filtering of waveform is done on a group of subcarriers. In OFDM it is done on the whole subcarriers together. This reduces
the side lobe levels, inters carrier interference (ICI) and requires reduced filter length. Moreover Internet-of-Things where
Machine-Machine communication and applications where very tight response in time requirements are needed, OFDM
miserably fails. We examine impact of carrier frequency offset on the performance of the proposed scheme and compare the
results performance of cyclic prefix based orthogonal frequency division multiplexing(CP-OFDM) system.-
Key words: ICI,CFO,OFDM,UFMC
This document summarizes the implementation and bit error rate analysis of BPSK modulation and demodulation using MATLAB. It first introduces digital communication systems and BPSK modulation. It then describes the modulation and demodulation processes for BPSK. The document shows the MATLAB simulations for BPSK modulation and demodulation. It also discusses bit error rate analysis for BPSK and gives the equation for calculating bit error rate based on signal energy per bit and noise spectral density.
Dynamic Spectrum Derived Mfcc and Hfcc Parameters and Human Robot Speech Inte...IDES Editor
Using the Mel-frequency cepstral coefficients
(MFCC), Human Factor cepstral coefficients (HFCC) and
their new parameters derived from log dynamic spectrum and
dynamic log spectrum, these features are widely used for
speech recognition in various applications. But, speech
recognition systems based on these features do not perform
efficiently in the noisy conditions, mobile environment and
for speech variation between users of different genders and
ages. To maximize the recognition rate of speaker independent
isolated word recognition system, we combine both of the above
features and proposed a hybrid feature set of them. We tested
the system for this hybrid feature vector and we gained results
with accuracy of 86.17% in clean condition (closed window),
82.33% in class room open window environment, and 73.67%
in outdoor with noisy environment.
Channel Estimation In The STTC For OFDM Using MIMO With 4G SystemIOSR Journals
This document summarizes a research paper on channel estimation in space-time trellis coding (STTC) for orthogonal frequency division multiplexing (OFDM) using multiple-input multiple-output (MIMO) technology in 4G wireless systems. It describes how STTC achieves transmit diversity by using specially designed channel codes at the transmitter along with signal processing at the receiver. Simulation results show that STTC for OFDM-MIMO systems can achieve a bit error rate of 10-5 at lower signal-to-noise ratios when using phase-shift keying modulation schemes like 2-PSK, 4-PSK, 8-PSK and 16-PSK. Decoding techniques like minimum mean square error, zero forcing and
Performance analysis of Adaptive Bit-interleaved Coded Modulation in OFDM usi...IOSR Journals
This document discusses the performance analysis of Adaptive Bit-interleaved Coded Modulation (ABICM) in OFDM using a Zero Padding Scheme (ZPS). It begins with background on OFDM and techniques like ABICM, CP-OFDM, and ZP-OFDM. It then presents the system model for the proposed ABICM-OFDM-ZPS scheme. Next, it analyzes and compares CP-OFDM and ZP-OFDM, noting benefits of ZP like reduced power back-off and wider spectrum. Finally, it discusses how ABICM is applied to the proposed ZP-OFDM system, using channel state information and bit interleaving to improve performance over
This document discusses simulation of OFDM modulation adapted for fixed image transmission over disturbed channels. It presents results from a MATLAB simulation of an OFDM system using various modulation schemes (BPSK, QPSK, 16PSK, 256PSK) with and without convolutional coding. The system is evaluated based on received image quality, SNR, BER, and other parameters when using a standard guard interval of 25% of the symbol period versus a modified shorter guard interval. Results show image quality of 98% can be achieved with the classic OFDM system using a 25% guard interval when convolutional coding is added to improve transmission quality over noisy channels.
1) OFDM uses multiple carriers to transmit data in parallel. It can be described mathematically using the Fourier transform which relates events in the time and frequency domains.
2) At the transmitter, the signal is defined in the frequency domain using a discrete Fourier transform and generated using the inverse discrete Fourier transform. This allows the carriers to be orthogonal.
3) A guard interval is added between symbols to prevent intersymbol interference from multipath distortion. This increases the symbol duration and provides timing tolerance at the receiver.
IMPROVEMENT OF LTE DOWNLINK SYSTEM PERFORMANCES USING THE LAGRANGE POLYNOMIAL...IJCNCJournal
The document describes research on improving the performance of LTE downlink systems using Lagrange polynomial interpolation for channel estimation. It presents the MIMO-OFDM transmission scheme used in LTE and discusses various channel estimation techniques including linear, sinus cardinal, Newton polynomial, and Lagrange polynomial interpolation. Simulation results show that Lagrange polynomial interpolation outperforms other methods in terms of block error rate, throughput, and error vector magnitude versus signal-to-noise ratio. The optimal order of the Lagrange polynomial is determined by evaluating performance for different orders.
Analyse Performance of Fractional Fourier Transform on Timing and Carrier Fr...ijwmn
This paper deals with the performance of the use of fractional Fourier transform (FRFT) instead of
conventional Fourier transform (FFT) in either symbol timing offset (STO) and carrier frequency offset
(CFO) estimation. Orthogonal frequency division multiplexing is widely used in many systems due to
advantages of theses technique compared with mono-carrier systems. In spite of his advantages, OFDM
presents drawbacks such as sensitivity to timing and frequency offsets. Many techniques are used in the
literature to estimate these two parameters in order to compensate them (synchronization task). These
techniques used conventional Fourier transform. In this paper, we are interested in estimating STO and
CFO using fractional Fourier transform. Monte Carlo simulation demonstrates the performance of the use
of FRFT instead of FFT.
Energy Efficiency of MIMO-OFDM Communication SystemIJERA Editor
The document discusses the energy efficiency of MIMO-OFDM communication systems. It begins with an introduction to the need for high-speed communication networks to meet increasing data demands. It then describes how MIMO and OFDM technologies can be combined to enhance data rates over frequency-selective fading channels. The document presents the system model of a MIMO-OFDM system using adaptive beamforming to mitigate co-channel interference at the satellite. Simulation results using MATLAB show that MIMO-OFDM systems have better performance than other modulation schemes in terms of lower bit error rate and mean square error.
Multi carrier equalization by restoration of redundanc y (merry) for adaptive...IJNSA Journal
This paper proposes a new blind adaptive channel shortening approach for multi-carrier systems. The
performance of the discrete Fourier transform-DMT (DFT-DMT) system is investigated with the proposed
DST-DMT system over the standard carrier serving area (CSA) loop1. Enhanced bit rates demonstrated
and less complexity also involved by the simulation of the DST-DMT system.
PAPR REDUCTION OF OFDM SIGNAL BY USING COMBINED HADAMARD AND MODIFIED MEU-LAW...IJCNCJournal
Orthogonal frequency division multiplexing (OFDM) is a technique which gives high quality of service (QOS) to the users by mitigating the fading signals as well as high data rates in multimedia services. However, the peak-to-average power ratio (PAPR) is a technical challenge that reduces the efficiency of RF power amplifiers. In this paper, we propose the combined Hadamard transform and modified meu-law companding transform method in order to lessen the effects of the peak-to-average power ratio of the
OFDM signal. Simulation results show that the proposed scheme reduces PAPR compared to other companding techniques as well as the Hadamard transform technique when used on its own.
IRJET- Survey Paper on Paper Reduction for MIMO-OFDM Systems using PTS SchemeIRJET Journal
This document summarizes research on techniques to reduce peak-to-average power ratio (PAPR) in MIMO-OFDM systems. It discusses how PAPR significantly affects OFDM and can cause nonlinearity in high power amplifiers. The paper focuses on using partial transmit sequence techniques to reduce PAPR. It reviews related work applying techniques like iterative clipping and filtering, partial transmit sequences, and adaptive selected mapping to reduce PAPR. The document also discusses system models for MIMO-OFDM and analyzing PAPR reduction performance.
Design of Simulink Model for Constant Envelop OFDM & Analysis of Bit Error RateIJSRD
This paper describes a transformation technique aimed at solving the peak-to-average power ratio (PAPR) problem associated with OFDM (Orthogonal Frequency Division Multiplexing). The Constant Envelop-OFDM solves the problem of high peak-to-average power ratio (PAPR) in OFDM, reducing PAPR to 0 dB. The constant envelope signal can be efficiently amplified with nonlinear power amplifiers thus achieving greater power efficiency. It is shown that CE-OFDM’s performance is better than conventional OFDM when taking into account the effects of the power amplifier. The performance of CE-OFDM is analyzed in additive white Gaussian noise (AWGN) channel. CE-OFDM is shown to achieve good performance with the use of cyclic prefix transmission. By way of computer simulation, CE-OFDM is shown to compare favorably to conventional OFDM. OFDM and CE-OFDM is analyzed on grounds of BER with additive white Gaussian noise (AWGN). The BER is calculated and the performance of OFDM and CE OFDM is compared.
Orthogonal Frequency Division Multiplexing with Offset Quadrature Amplitude Modulation
(OFDM / OQAM) is a multicarrier modulation scheme that can be considered as an alternative
to the conventional Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix
(CP) for transmission over multipath fading channels. In this paper, we investigate the
combination of the OFDM/OQAM with Alamouti system with Time Reversal (TR) technique.
TR can be viewed as a precoding scheme which can be combined with OFDM/OQAM and
easily carried out in a Multiple Input Single Output (MISO) context such as Alamouti system.
We present the simulation results of the performance of OFDM/OQAM system in SISO case
compared with the conventional CP-OFDM system and the performance of the combination
Alamouti OFDM / OQAM with TR compared to Alamouti CP-OFDM. The performance is
derived by computing the Bit Error Rate (BER) as a function of the transmit signal-to-noise
ratio (SNR).
Spatial multiplexing ofdmoqam systems with time reversal techniqueijwmn
Orthogonal Frequency Division Multiplexing with Offset Quadrature Amplitude Modulation (OFDM/OQAM) is a multicarrier modulation scheme that can be considered as an alternative to the conventional Orthogonal Frequency Division Multiplexing (OFDM) with Cyclic Prefix (CP) for transmission over multipath fading channels. In this paper, we investigate the combination of the OFDM/OQAM with Multiple Input Multiple Output (MIMO) system with Time Reversal (TR) technique.
TR can be viewed as a precoding scheme which can be combined with OFDM/OQAM and easily carried out in a MIMO context using spatial data multiplexing.
We present the simulation results of the performance of OFDM/OQAM system in SISO case compared with the conventional CP-OFDM system and the performance of the combination MIMO-OFDM/OQAM with TR compared to MIMO-CP-OFDM. The performance is derived by computing the Bit Error Rate (BER) as a function of the transmit signal-to-noise ratio (SNR).
This document summarizes a research paper that evaluates the performance of different MIMO techniques for MIMO-OFDM systems. It describes spatial multiplexing (SM), space time block coding (STBC), and a hybrid model combining SM and STBC. A simulation model of a 4x4 antenna hybrid MIMO-OFDM system is developed. Results show the hybrid system provides lower bit error rates than SM or STBC systems alone, improving both data rate and link reliability for wireless communication.
Phydyas 09 fFilter Bank Multicarrier (FBMC): An Integrated Solution to Spectr...Marwan Hammouda
The document discusses filter bank multicarrier (FBMC) as a solution for spectrum sensing and data transmission in cognitive radio networks. Conventional OFDM has limitations for these tasks due to its sidelobe leakage, which causes interference between primary and secondary users. FBMC uses a filter bank approach instead of FFT to provide better frequency localization and reduce sidelobe leakage without reducing bandwidth efficiency. The document outlines the benefits of FBMC over OFDM for spectrum sensing and sharing in cognitive radio.
An Adaptive Approach to Switching Coded Modulation in OFDM System Under AWGN ...ijsrd.com
In this paper we have studied the OFDM for different Quadrature amplitude modulation technique (QAM) The scatter plot and their output signal to noise ratio, dependent bit error rate variation is analyzed for every type of modulation in OFDM. After observing the BER for each SNR in the system, switching threshold range has been prepared and now system is ready to face the Adaptive coded modulation (ACM).The results shows the switching of modulation technique.
The International Journal of Engineering and Science (The IJES)theijes
1. The document proposes an efficient method for inter-carrier interference (ICI) cancellation and peak-to-average power ratio (PAPR) reduction in MIMO-OFDM wireless systems.
2. It develops an expectation-maximization algorithm to jointly estimate carrier frequency offset and channel impulse response. It also designs a minimum mean-square error precoding matrix to reduce PAPR.
3. The key contribution is a progressive parallel inter-carrier interference canceller based on factor graphs. It iteratively reconstructs and cancels ICI across subcarriers in both the frequency and space domains to improve performance.
This document summarizes a research paper that proposes a modified channel shortener filter (MCSF) to improve the spectral efficiency of OFDM systems. The MCSF exploits the null space of an underdetermined system of equations to provide multiple independent equivalent channels to the receiver. It is shown that the MCSF can achieve a higher spectral efficiency than conventional OFDM when the cyclic prefix length is significantly smaller than the channel delay spread. Simulation results demonstrate that the MCSF improves bit error rate performance and can provide up to 2dB gain compared to full cyclic prefix OFDM systems. The MCSF has the potential to reduce receiver complexity compared to existing channel shortening approaches.
Implementation and Study of Universal Filtered Multi Carrier under Carrier Fr...Editor IJAIEM
Sathiyapriya N.S
PG Student, Dept. of ECE, Periyar Maniammai University Thanjavur, Tamilnadu, India
ABSTRACT
OFDM is a matured technology and applied in various wireless standards. However they are not suitable for Uplink and this
technology is replaced by SC FDMA in 4G standards. Similarly Universal Filtered Multicarrier Communication (UFMC) is
another suitable technology for Multi user Uplink and for applications like cognitive radio. UFMC is a new, non-orthogonal,
waveform designed by Alcatel Lucent Labs which provide a much more efficient way of enabling networks to serve both
broadband users and very narrowband “short data” devices such as any embedded sensor or M2M module. In UFMC the
filtering of waveform is done on a group of subcarriers. In OFDM it is done on the whole subcarriers together. This reduces
the side lobe levels, inters carrier interference (ICI) and requires reduced filter length. Moreover Internet-of-Things where
Machine-Machine communication and applications where very tight response in time requirements are needed, OFDM
miserably fails. We examine impact of carrier frequency offset on the performance of the proposed scheme and compare the
results performance of cyclic prefix based orthogonal frequency division multiplexing(CP-OFDM) system.-
Key words: ICI,CFO,OFDM,UFMC
This document summarizes the implementation and bit error rate analysis of BPSK modulation and demodulation using MATLAB. It first introduces digital communication systems and BPSK modulation. It then describes the modulation and demodulation processes for BPSK. The document shows the MATLAB simulations for BPSK modulation and demodulation. It also discusses bit error rate analysis for BPSK and gives the equation for calculating bit error rate based on signal energy per bit and noise spectral density.
Dynamic Spectrum Derived Mfcc and Hfcc Parameters and Human Robot Speech Inte...IDES Editor
Using the Mel-frequency cepstral coefficients
(MFCC), Human Factor cepstral coefficients (HFCC) and
their new parameters derived from log dynamic spectrum and
dynamic log spectrum, these features are widely used for
speech recognition in various applications. But, speech
recognition systems based on these features do not perform
efficiently in the noisy conditions, mobile environment and
for speech variation between users of different genders and
ages. To maximize the recognition rate of speaker independent
isolated word recognition system, we combine both of the above
features and proposed a hybrid feature set of them. We tested
the system for this hybrid feature vector and we gained results
with accuracy of 86.17% in clean condition (closed window),
82.33% in class room open window environment, and 73.67%
in outdoor with noisy environment.
Channel Estimation In The STTC For OFDM Using MIMO With 4G SystemIOSR Journals
This document summarizes a research paper on channel estimation in space-time trellis coding (STTC) for orthogonal frequency division multiplexing (OFDM) using multiple-input multiple-output (MIMO) technology in 4G wireless systems. It describes how STTC achieves transmit diversity by using specially designed channel codes at the transmitter along with signal processing at the receiver. Simulation results show that STTC for OFDM-MIMO systems can achieve a bit error rate of 10-5 at lower signal-to-noise ratios when using phase-shift keying modulation schemes like 2-PSK, 4-PSK, 8-PSK and 16-PSK. Decoding techniques like minimum mean square error, zero forcing and
Performance analysis of Adaptive Bit-interleaved Coded Modulation in OFDM usi...IOSR Journals
This document discusses the performance analysis of Adaptive Bit-interleaved Coded Modulation (ABICM) in OFDM using a Zero Padding Scheme (ZPS). It begins with background on OFDM and techniques like ABICM, CP-OFDM, and ZP-OFDM. It then presents the system model for the proposed ABICM-OFDM-ZPS scheme. Next, it analyzes and compares CP-OFDM and ZP-OFDM, noting benefits of ZP like reduced power back-off and wider spectrum. Finally, it discusses how ABICM is applied to the proposed ZP-OFDM system, using channel state information and bit interleaving to improve performance over
This document discusses simulation of OFDM modulation adapted for fixed image transmission over disturbed channels. It presents results from a MATLAB simulation of an OFDM system using various modulation schemes (BPSK, QPSK, 16PSK, 256PSK) with and without convolutional coding. The system is evaluated based on received image quality, SNR, BER, and other parameters when using a standard guard interval of 25% of the symbol period versus a modified shorter guard interval. Results show image quality of 98% can be achieved with the classic OFDM system using a 25% guard interval when convolutional coding is added to improve transmission quality over noisy channels.
1) OFDM uses multiple carriers to transmit data in parallel. It can be described mathematically using the Fourier transform which relates events in the time and frequency domains.
2) At the transmitter, the signal is defined in the frequency domain using a discrete Fourier transform and generated using the inverse discrete Fourier transform. This allows the carriers to be orthogonal.
3) A guard interval is added between symbols to prevent intersymbol interference from multipath distortion. This increases the symbol duration and provides timing tolerance at the receiver.
IMPROVEMENT OF LTE DOWNLINK SYSTEM PERFORMANCES USING THE LAGRANGE POLYNOMIAL...IJCNCJournal
The document describes research on improving the performance of LTE downlink systems using Lagrange polynomial interpolation for channel estimation. It presents the MIMO-OFDM transmission scheme used in LTE and discusses various channel estimation techniques including linear, sinus cardinal, Newton polynomial, and Lagrange polynomial interpolation. Simulation results show that Lagrange polynomial interpolation outperforms other methods in terms of block error rate, throughput, and error vector magnitude versus signal-to-noise ratio. The optimal order of the Lagrange polynomial is determined by evaluating performance for different orders.
Analyse Performance of Fractional Fourier Transform on Timing and Carrier Fr...ijwmn
This paper deals with the performance of the use of fractional Fourier transform (FRFT) instead of
conventional Fourier transform (FFT) in either symbol timing offset (STO) and carrier frequency offset
(CFO) estimation. Orthogonal frequency division multiplexing is widely used in many systems due to
advantages of theses technique compared with mono-carrier systems. In spite of his advantages, OFDM
presents drawbacks such as sensitivity to timing and frequency offsets. Many techniques are used in the
literature to estimate these two parameters in order to compensate them (synchronization task). These
techniques used conventional Fourier transform. In this paper, we are interested in estimating STO and
CFO using fractional Fourier transform. Monte Carlo simulation demonstrates the performance of the use
of FRFT instead of FFT.
Energy Efficiency of MIMO-OFDM Communication SystemIJERA Editor
The document discusses the energy efficiency of MIMO-OFDM communication systems. It begins with an introduction to the need for high-speed communication networks to meet increasing data demands. It then describes how MIMO and OFDM technologies can be combined to enhance data rates over frequency-selective fading channels. The document presents the system model of a MIMO-OFDM system using adaptive beamforming to mitigate co-channel interference at the satellite. Simulation results using MATLAB show that MIMO-OFDM systems have better performance than other modulation schemes in terms of lower bit error rate and mean square error.
Study of timing synchronization in mimoofdm systems using dvb tijitjournal
This document summarizes a study on timing synchronization in MIMO-OFDM systems using DVB-T. It discusses the timing offset problem in OFDM systems and proposes a solution using the cyclic prefix as a modified Schmidl and Cox algorithm. Simulations were performed to implement the DVB-T system and compare different synchronization methods under an AWGN channel model. The results show that higher timing offsets require greater SNR to achieve the same BER performance. The proposed approach uses cyclic prefix correlation to determine timing offsets with less overhead compared to using a training sequence.
A JOINT TIMING OFFSET AND CHANNEL ESTIMATION USING FRACTIONAL FOURIER TRANSFO...IJCNCJournal
This paper proposes a new method for joint timing offset and channel estimation in OFDM systems using fractional Fourier transform and constant amplitude zero autocorrelation sequences. After estimating the timing offset in the frequency domain, compensation is performed in the time domain. Channel estimation then uses least squares with discrete Fourier transform and linear interpolation to recover the transmitted signal. Simulation results show the proposed method achieves good performance in terms of mean square error for timing offset estimation compared to other techniques, especially for fast fading channels. It also estimates the channel well while maintaining throughput.
Spectrum analysis of OFDM versus FBMC in 5G mobile communicationsTELKOMNIKA JOURNAL
This document provides a comparative analysis of OFDM and FBMC modulation techniques for 5G mobile communications. It summarizes the key differences between OFDM and FBMC, including that FBMC replaces the cyclic prefix of OFDM with synthesis and analysis filters on the transmitter and receiver sides. It then describes implementations of OFDM and FBMC transmitters and receivers using GNU Radio. Simulation results show that FBMC has better spectral containment compared to OFDM but higher complexity. OFDM is found to have better spectral efficiency and lower peak-to-average power ratio. The document concludes that OFDM overall has better performance than FBMC for 5G based on the parameters considered.
Multi-carrier Equalization by Restoration of RedundancY (MERRY) for Adaptive ...IJNSA Journal
This paper proposes a new blind adaptive channel shortening approach for multi-carrier systems. The performance of the discrete Fourier transform-DMT (DFT-DMT) system is investigated with the proposed DST-DMT system over the standard carrier serving area (CSA) loop1. Enhanced bit rates demonstrated and less complexity also involved by the simulation of the DST-DMT system.
Analysis of cyclic prefix length effect on ISI limitation in OFDM system over...IJECEIAES
In this work, the influence of the cyclic prefix on the performance of the OFDM system is studied. We worked out an OFDM transceiver using a 16 QAM modulation scheme, a comparison of the BER for various lengths of the cyclic prefix has been achieved, and the influence of the noise introduced in the channel has been highlighted, for both a Gaussian and Rayleigh noise. The simulation was carried out on MATLAB where the curves of the BER for various lengths of the cyclic prefix are given and compared. We also adopted as a metric the QAM constellation to show the dispersion of the carriers as a consequence of the transmission channel, the mitigation of this effect by the CP is noticeable.
An OFDM System Based on Dual Tree Complex Wavelet Transform (DT-CWT)CSCJournals
This document presents a study comparing an orthogonal frequency division multiplexing (OFDM) system based on dual-tree complex wavelet transform (DT-CWT) to conventional OFDM and wavelet packet modulation (WPM) based OFDM systems. The key findings are:
1) The proposed DT-CWT based OFDM system achieves significantly better bit error rate performance than conventional OFDM and WPM based OFDM systems.
2) The proposed system also achieves about 3 dB better peak-to-average power ratio performance compared to conventional OFDM and WPM based systems, indicating greater signal stability.
3) The performance of the proposed DT-CWT based OFDM system is not
A blind channel shortening for multiuser, multicarrier CDMA system over multi...TELKOMNIKA JOURNAL
In this paper we derive the Multicarrier Equalization by Restoration of Redundancy (MERRY) algorithm: A blind, adaptive channel shortening algorithm for updating a Time-domain Equalizer (TEQ) in a system employing MultiCarrier Code Division Multiple Access (MC-CDMA) modulation. We show that the MERRY algorithm applied to the MC-CDMA system converges considerably more rapidly than in the Orthogonal Frequency Division Multiplexing (OFDM) system [1]. Simulations results are provided to demonstrate the performance of the algorithm.
Peak detection using wavelet transformIJCNCJournal
A new work based-wavelet transform is designed to overcome one of the main drawbacks that found in the
present new technologies. Orthogonal Frequency Division Multiplexing (OFDM)is proposed in the
literature to enhance the multimedia resolution. However, the high peak power (PAPR) values will obstruct
such achievements. Therefore, a new proposition is found in this work, making use of the wavelet
transforms methods, and it is divided into three main stages; de-noising stage, thresholding stage and then
the replacement stage.
In order to check the system stages validity; a mathematical model has been built and its checked after
using a MATLAB simulation. A simulated bit error rate (BER) achievement will be compared with our
previously published work, where an enhancement from 8×10-1 to be 5×10-1 is achieved. Moreover, these
results will be compared to the work found in the literature, where we have accomplished around 27%
PAPR extra reduction.
As a result, the BER performance has been improved for the same bandwidth occupancy. Moreover and
due to the de-noise stage, the verification rate has been improved to reach 81%. This is in addition to the
noise immunity enhancement.
Hybrid PAPR Reduction Scheme for Universal Filter Multi-Carrier Modulation in...CrimsonPublishersRDMS
Hybrid PAPR Reduction Scheme for Universal Filter Multi-Carrier Modulation in Next Generation Wireless Systems by Himanshu Monga* in Crimson Publishers: Peer Reviewed Material Science Journals
Orthogonal Frequency Division Multiplexing (OFDM) is of great interest for the development of
the fifth-generation technology. It is the cornerstone of Multiple-input multiple-output (MIMO) systems.
Even though inter carrier interference (ICI) and inter symbol interference (ISI) have been processed for
the fourth-generation standards, they still present a huge problem for the fifth-generation standards. This
paper explores the tradeoff between the length of the cyclic prefix and the performances of the OFDM
system. It also studies the effect of carrier frequency offset (CFO) on OFDM systems. A blind frequency
offset estimator that uses the correlations between the remodulated sequence in the receiver side and
the conventional received symbol is presented and a closed form solution is derived. The proposed
estimator is derived under short interval when the correlation is high, so it has low computational
complexity. Lin and Beek’s estimators are used for comparison. Simulations demonstrate the effectiveness
of the proposed estimator under Rayleigh fading channel.
Analyses and performance of techniques papr reduction for stbc mimo ofdm syst...ijwmn
An OFDM system is combined with multiple-input mult
iple-output (MIMO) in order to increase the
diversity gain and system capacity over the time va
riant frequency-selective channels. However, a maj
or
drawback of MIMO-OFDM system is that the transmitte
d signals on different antennas might exhibit high
peak-to-average power ratio (PAPR).In this paper, w
e present a PAPR analysis reduction of space-time-
block-coded (STBC) MIMO-OFDM system for 4G wireless
networks. Several techniques have been used to
reduce the PAPR of the (STBC) MIMOOFDM system: clip
ping and filtering, partial transmit sequence
(PTS) and selected mapping (SLM). Simulation result
s show that clipping and filtering provides a bette
r
PAPR reduction than the others methods and only SLM
technique conserve the PAPR reduction in
reception part of signal.
Ofdm oqam performances for high speed optical communication in long haul fibe...IAEME Publication
This document describes a study of OFDM/OQAM modulation for high-speed optical communications over 1600 km of single mode fiber. OFDM/OQAM combines Orthogonal Frequency Division Multiplexing (OFDM) with Offset Quadrature Amplitude Modulation (OQAM) and uses analysis and synthesis filter banks. The study shows that filtered OFDM/OQAM provides better transmission performance than classical OFDM, requiring less or no equalization over longer distances. Simulation results in VPI Photonics software show that adjusting filter bank parameters and using 4QAM or 16QAM modulation improves the system performance measured by error vector magnitude, bit error rate, and Q-factor over varying optical signal-to-noise ratios.
This document discusses the implementation of different types of transmultiplexer (TMUX) structures for filter bank multicarrier systems. It describes maximally decimated, non-maximally decimated, and partial TMUX structures. For each structure, the analysis and synthesis filter banks are designed such that the filters are complex modulated versions of a prototype filter. Frequency sampling is used to design the prototype filter. Simulation results show perfect reconstruction is achieved for the maximally decimated TMUX, while non-maximally decimated TMUX achieves nearly perfect reconstruction. The partial TMUX relaxes the perfect reconstruction condition to allow for small distortions.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
This document discusses the effects of time offset (TO) and carrier frequency offset (CFO) on orthogonal frequency division multiplexing (OFDM) systems and proposes interference cancellation techniques. It introduces the OFDM system model and how CFO causes loss of orthogonality between subcarriers, resulting in inter-carrier interference (ICI) that degrades performance. The paper proposes an ICI reduction scheme using self-cancellation and evaluates its performance compared to standard OFDM. It also discusses using space-time block coding (STBC) with OFDM to improve performance by reducing bit error rate (BER) under different signal-to-noise ratios. Simulation results show STBC effectively mitigates the effects of inter-
Similar to Low complexity DCO-FBMC visible light communication system (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.
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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
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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%.
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According to Fourier transforms properties, for traditional OFDM, if the discrete input sequence of
the modulator has its first and center coefficients null, and if it presents Hermitian symmetry with respect to its
center, then the OFDM time modulated signal is real [12], while existing an OFDM instituted modulation,
FBMC inherits from many features related to traditional OFDM systems [13]. Nevertheless, the Hermitian
symmetry of the frequency symbols ends in a duplicated size of FFT/IFFT components [14]. Consequently,
to modulate N frequency symbols, 2N-point IFFT/FFT transforms are required [15]. This increases
the complexity of the system described. In [16] and [17] the authors presented a new technique to solve this
problem in the OFDM system and obtain a real signal without resorting to the use of Hermitian symmetry.
In this paper, first time investigated the new DCO-FBMC system in the VLC system without using
Hermitian symmetry and get real signal compatible with IM/DD to reduce the complexity of the DCO-FBMC
system and less power consuming. Moreover, the performance of the new technology has been demonstrated
to have a bit error rate (BER) where it is found to do the same performance as conventional technology.
2. CONVENTIONAL DCO-FBMC IN VLC
FBMC is one of the most promising modulation techniques in the field of optical communications,
because it provides high spectral efficiency besides other advantages. Like any modulate methods of optical
communication technology, the outgoing signal must be real and positive [18]. In this kind of systems serial
data are input to the division of data in parallel and are set in frequency of which usually employ offset
quadrature amplitude modulation (OQAM). In order to obtain real FBMC signal the input frequency symbols
to the IFFT are forced to have Hermitian symmetry [10]. The FBMC transmitted signal can be expressed
as follows:
𝑥(𝑛) = ∑ ∑ 𝑎 𝑚,𝑛 𝑔 𝑚,𝑛(𝑡)
2𝑁−1
𝑚=0
+∞
𝑛=−∞
(1)
where, m is the time index; and n is the subcarrier index; ɑm,n is the symbol (massage) being transmitted; N is
the number of subcarriers; and g(t) is the synthesis function which maps ɑm,n into the signal space; gm,n(t) is
the shifted version in time and frequency as (2) [19].
𝑔 𝑚,𝑛(𝑡) = ℎ(𝑛 − 𝑚𝒯0)𝑒
𝑗2𝜋/𝑁𝑘(𝑛−
𝐿 𝑝−1
2
)
𝑒 𝑗Φ 𝑚,𝑛 (2)
where, τ0 is the symbol spacing in time; Lp is the length of the pulse shaping filter (LP=K*N); K is
the overlapping factor; h(n) is the pulse shaping filter (known prototype filter).k is the subcarrier index.
ℎ(𝑛) = 1 + 2 ∑(−1) 𝑘
𝐻𝑘 cos(2𝜋
𝑘𝑛
𝐿 𝑃
)
𝐾−1
𝑘=1
(3)
Hk is set of coefficients related to K [20].
As a result of the use of Hermitian symmetric and the properties of the Inverse Fast Fourier
Transformer (IFFT), the imaginary signal is excluded and the outgoing signal is real as shown in Figure 1.
Figure 1 shows that M = N / 2. This means that only half of the sub-carriers are used, while the other half is
excluded as a result of the use of Hermitian symmetry. It is needed 2N size symbol FFT to get N size.
The system will suffer from high energy consumption and occupy higher chip area [21].
Figure 1. IFFT signal after hermitian symmetry showed the output for real signal and imaginary signal
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3. NEW TECHNIQUE DCO-FBMC
The use of Hermitian symmetry in modulation systems was necessary to generate a real signal,
because this is a major condition in VLC, but there are disadvantages of this technique including increasing
the complexity, which leads to doubling the size of IFFT/ FFT. This motivation prompted researchers in [8, 9]
to find a new technique for generating a real signal in the OFDM system without using Hermitian symmetry.
In this research, the same technique was implemented in the FBMC technique, but in different steps as follows.
3.1. Design new optical DCO-FBMC transmitter
The transmitted design of FBMC as shown in Figure 2, the incoming symbols are processed into
the OQAM block where each symbol is filtered using the pulse shaping filter in (2) and each sub-carrier real
symbol (am,n) which corresponds to the real part or the imaginary part of the complex FBMC. The transmitted
signal must be a real signal, but the signal coming out of the IFFT and passing from P/S (parallel to serial
converter) is a complex one (consisting of a real part and an imaginary part), and hence the imaginary part
must be converted into a real part. The complex signal must be separated into two parts; real and imaginary
part, then Juxtaposed technique is done which means laying the imaginary part in sequence with the real part.
Figure 2. New DCO-FBMC optical transmitter block diagram
The frequency vector, ɑm,n, is directly inputted to an N-point IFFT as in traditional complex FBMC
systems since no Hermitian symmetry limitation is decreed, the IFFT output signal is complex and can be
expressed in (4).
𝑥(𝑛) = ∑ ∑ 𝑎 𝑚,𝑛 𝑔 𝑚,𝑛(𝑡)
𝑁−1
𝑚=0
+∞
𝑛=−∞
(4)
The complex time signal can be expressed precisely in (5). This technique is applied after P/S block.
𝑥(𝑛) = 𝑎(𝑛) + 𝑗𝑏(𝑛), 𝑛 = 1,2,3, … . 𝐾 ∗ (𝑁 − 1) (5)
where ɑ and b are respectively the real and imaginary components of x(n). The KN-point real and imaginary
parts of the generated in the time domain complex signal are Juxtaposed after P/S, this process generated
2-KN real FBMC in (6).
𝑥2𝐾𝑁 = {
𝑎(𝑛) 𝑛 = 0, … . . , 𝐾(𝑁 − 1)
𝑏(𝑛 − 𝐾𝑁) 𝑛 = 𝐾𝑁, … . . ,2𝐾(𝑁 − 1)
(6)
Figure 3 shows the real signal and the imaginary signal after their separation before applying the new
technique. After that, the imaginary juxtaposed real signal in the new technique is applied as in Figure 4, thus,
it is noted that the signal length is 2KN. The signal’s emerging after the application of juxtaposed technology
is bipolar, for one of the most important conditions of the signal must be positive, and that is a unipolar signal.
DC-biased optical FBMC is one of the simplest and primitive approaches that were proposed to generate
unipolar FBMC system compatible with IM/DD systems. The DC bias desired to assure non-negativity is
equivalent to the absolute value of the negative greatest amplitude of the bipolar FBMC signal. the method is
to employ a DC-bias Bdc proportional to the root square of electric power (σ) as in (7) [22].
𝐵 𝑑𝑐 = 𝑏𝜎 (7)
where b is the clipping factor and σ2
is the variance of x(n) defied as,
𝜎2
= 𝛦{𝑥2
(𝑛)} (8)
4. Int J Elec & Comp Eng ISSN: 2088-8708
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This is defined in [15] as a bias of 10𝑙𝑜𝑔10(𝑘2
+ 1)𝑑𝐵.the DC-bias
𝑥 𝐷𝐶(𝑛) = 𝑥(𝑛) + 𝐵 𝑑𝑐 (9)
Figure 5 shows the new propose DCO-FBMC at 13.6dB negative clipping.
Figure 3. Output real and imaginary FBMC signal after separated
Figure 4. Imaginary signal juxtaposed to real signal at length 2LP
Figure 5. Add DC-bias optical to the signal at (13.6dB)
3.2. Design new dco-FBMC receiver
When the optical signal is received at the photodetector, the optical signal is converted to an electrical
signal. Then the first step is to remove the DC-bias effect and then the real signal is separated from
the imaginary part according to (10).
𝑦(𝑛) = {
𝑎 𝑟(𝑛) = 𝑦2𝐾𝑁(𝑛), 𝑛 = 0, . , 𝐾(𝑁 − 1)
𝑏 𝑟(𝑛) = 𝑦2𝐾𝑁(𝐾𝑁 + 𝑛) 𝑛 = 0, . . , 𝐾(𝑁 − 1)
(10)
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where ɑr and br are respectively the real and imaginary components of received signal y(n) then reshaped
the complex then pass the signal to analysis filter bank demodulation as the conventional FBMC system all
this shows in the block diagram in Figure 6.
Figure 6. New design DCO-FBMC receiver block diagram
4. COMPUTIONAL COMPLEXITY
The FBMC technology is a complex technique, but it has advantages that distinguish it from the rest
of the systems used in VLC. A new technique called Juxtaposing is proposed to reduce this complexity and
obtain a real signal instead of using the traditional techniques as shown in Figure 7 and Figure 8, to calculate
the complexity divided into two parts multiplications and additions using the Radix-2FFT algorithm [23].
Figure 7 and Figure 8 illustrate the comparison between the complexity of new technology and traditional
technology calculated according to equation (11) and (12) for new techniques, and (13) and (14) for
conventional [24, 25].
𝐶 𝑚𝑛𝑒𝑤 = 𝑁(𝑙𝑜𝑔2( 𝑁
2⁄ ) − 3) + 8 + 4(𝑁𝐾 + 1) (11)
𝐴 𝑎𝑛𝑒𝑤 = 3𝑁(𝑙𝑜𝑔2( 𝑁
2⁄ ) − 1) + 8 + 4(𝑁𝐾 − 𝑁 + 1) (12)
𝐶 𝑚𝑐𝑜𝑛 = 2𝑁(𝑙𝑜𝑔20(𝑁) − 3) + 8 + 4(2𝑁𝐾 + 1) (13)
𝐴 𝑎𝑐𝑜𝑛 = 6𝑁(𝑙𝑜𝑔2(𝑁) − 1) + 8 + 4(𝑁𝐾 − 𝑁 + 1) (14)
Figure 7. FBMC multiplication complexity Figure 8. FBMC additional complexity
where, Cmnew, Aanew ,Canew, and Aacon respectively are multiplications and additional calculation of new and
conventional DCO-FBMC technique. The Figures explained that the new technology offers a complexity of
about 50% less than conventional technology. When the FFT / IFFT size increases, both power consumption
and the occupied chip area are increased.
6. Int J Elec & Comp Eng ISSN: 2088-8708
Low complexity DCO-FBMC visible light communication system (Abdullah A. Qasim)
933
5. BER PERFORMACE
Figure 9 shows the simulation results for the BER of conventional technology and new proposed
DCO-FBMC technology as a signal to noise ratio (SNR) in dB function. These simulators were made under
DCO-FBMC of 1000 symbols for various M-QAM in AWGN constellations from 4QAM to 256QAM.
Therefore when using N size for FFT / IFFT to the performance of the term SNR will provide good indications
of DCO-FBMC where the results are the same as the conventional technique.
Figure 9. The BER of the function SNR dB of the New DCO-FBMC and conventional method
(new DCO-FBMC IFFT size 512) and the (Conventional DCO-FBMC IFFT size 1024) for different M-QAM
6. CONCLUSION
In this research, new technology was created to generate a real signal from DCO-FBMC compatible
with IM/DD. The proposed technique consists of generating a traditional complex FBMC signal and then
extracting the real and imaginary parts juxtaposed with them in the time domain to get a real FBMC signal.
This, in turn, led to a significant reduction in the complexity and thus to reduce power consumption and
occupied chip area. It was also explained that the performance of the proposed FBMC technology in terms of
BER is the same as the performance of traditional technology.
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