Minimum Bit Error Rate Research Articles

Performance analysis of Q-factor on wavelengths and bit rates using optical solitons with dispersion management

In this paper, the dispersion management using soliton pulses in optical communication system is studied. The performance of the system with and without soliton parameters in terms of Q-factor, BER, and eye diagram is also studied. The proposed system with soliton parameters provides an improvement in Q-factor value by 82.1118 dB compared to that without soliton parameters at bit rate of 20 Gbps at a wavelength of 1550 nm with minimum BER of 0. Thus, soliton pulse can be transmitted dispersion free over optical fiber due to the exact compensation between nonlinearity and group velocity dispersion. The impact of wavelengths and bit rates for the soliton system on Q-factor, BER, and eye height is also investigated. The analysis of the simulation results provides that the values of Q-factor and eye height are inversely proportional to wavelength and proportional to bit rates in the proposed system with soliton parameters. Besides, it is proposed that the soliton pulse is best suited for long-range communication system with dispersion management.

A Generalized Dimming Control Scheme for Visible Light Communications

A novel dimming control scheme, termed as generalized dimming control (GDC), is proposed for visible light communication (VLC) systems. The basic idea of GDC is to exploit adaptively time, spatial and signal domain resources for enhancing communication performance under practical illumination constraints. In particular, to satisfy the illumination constraints, an incremental algorithm for index mapping is first proposed to achieve target optical power and uniform illumination. Next, GDC having the optimal activation pattern is investigated to improve the bit-error rate (BER) performance of VLC. In particular, the BER performance of GDC is analyzed using the union bound technique. Based on the analytical BER bound, the optimal activation pattern of GDC scheme having the minimum BER criterion (GDC-MBER) is obtained by exhaustively searching all conditional pairwise error probabilities. However, since GDC-MBER requires high search complexity, two low-complexity GDC schemes having the maximum free distance criterion (GDC-MFD) are proposed. The first low-complexity GDC-MFD scheme, termed as GDC-MFD1, is derived by a lower bound of the free distance using the Rayleigh-Ritz theorem. The second low-complexity GDC-MFD scheme, termed as GDC-MFD2, is proposed to reduce further the computation by exploiting the time-invariance characteristics of the VLC channel. Simulation and numerical results show that GDC-MBER, GDC-MFD1 and GDC-MFD2 have similar BER performance, and they can achieve more than 3 dB SNR gains compared with conventional dimming control schemes for a BER of ${10^{ - 4}}$ and a dimming level of 50%.

An Adaptive Neuro Fuzzy Inference System (ANFIS) Based Relay Selection Scheme for Cooperative Wireless Sensor Network

Cooperative communication in wireless sensor network has emerged a solution of energy limitation of sensor nodes. Relay selection in cooperative communication plays an important role to improve the performance of energy constrained networks. In such networks, to make balance between network lifetime (NL) and Bit Error Rate (BER) is the difficult task for the researchers. Although, the minimization of BER can be achieved by choosing best possible relay to destination link which has lowest path loss, but this solution cannot gives guarantee to enhance the NL because some nodes are frequently selected for retransmission of the information. On the other hand, increase the NL is possible by efficiently distribution of energy consumption among all the available relay nodes. In this paper, we propose an Adaptive Neuro Fuzzy Inference System based Relay Selection (ANFISRS) scheme where residual energy of the relay node and path loss of the channel are considered as an input parameters for the relay selection. ANFISRS makes balance between these two parameters for improving network lifetime and BER. Furthermore, the proposed method is compared with three existing strategies: Random Relay Selection, Maximum Residual energy based Relay Selection, and Minimum Energy Consumption based relay selection. The proposed scheme considerably reduces the BER while enhance the network lifetime over the existing strategies.

Low-Complexity PAPR Reduction Method for OFDM Systems Based on Real-Valued Neural Networks

High peak-to-average power ratio (PAPR) in orthogonal frequency division multiplexing (OFDM) systems is one of the major drawbacks in wireless transmitters. In this letter, a novel low complexity PAPR reduction method based on the real-valued neural network (NN) is proposed. This method first builds the PAPR reduction module using the real-valued NN to achieve the reduction of PAPR. To reconstruct the transmission signal, the PAPR decompression module is introduced into the receiving end to recover the signal in order to minimize the bit error rate (BER) of the systems. The PAPR reduction module and the PAPR decompression module can be jointly trained offline, therefore, the reduction of PAPR and the minimization of BER can be achieved simultaneously. To reduce the process rate of the PAPR reduction, the trained model uses multiple parallel processing links to achieve the reduction of the PAPR. The extensive simulations indicate that the proposed method outperforms previously available methods in terms of PAPR and BER, while having low complexity.

Design of 80 Gbps Free Space Optics for Clear Weather Condition

Free Space Optics (FSO) is a promising technology and proven its major utility as redundancy for existing fiber optic long haul networks and in metropolitan area networks. However, as it is using air as an unguided medium, FSO has an impact on its performance due to different atmospheric conditions. It has a significant effect on determining the maximum range and maximum data rate. The researchers are working to enhance the performance of the FSO system employing varying multiplexing and modulation techniques. The available long-range wavelength division multiplexed (WDM) FSO system for clear weather conditions has a channel capacity of 10 Gbps (2.5 Gbps x 4 channels). In this paper, a four-channel WDM –FSO system is designed to operate in O, E, L, and U bands. The developed method is optimized to enhance channel capacity to 80 Gbps (20 Gbps x 4 channels) for an extended range of 150 km with a maximum Q factor of 6.44 and a minimum BER of 5.96 e-11.

Companding Schemes for Reducing PAPR in OFDM System: A Review

AbstractHigh PAPR poses a large hindrance to high data rate Orthogonal Frequency Division Multiplexing (OFDM) signals. A companding transform converts the Probability distribution function (PDF) of the transmitted OFDM signal in a way which reduces the Peak-to-average power-ratio (PAPR). In this paper, we have performed the study of companding techniques and analyzes the PAPR and BER performances of these schemes. Here, we have considered μ-law companding, exponential companding, trapezoidal companding (TC) and trigonal companding for comparison. In this paper, we have demonstrated that μ-law companding, exponential companding and trigonal companding schemes have no adaptability in designing the companding function, and along these lines an exchange off between BER performance and PAPR reduction ability is unrealistic to accomplish. However, TC scheme has two parameters (a and b) to design the companding function and hence a trade-off between PAPR reduction capability and BER performance is possible to achieve. BER performance and PAPR reduction capabilities of the scheme under consideration are evaluated and compared through computer simulations. We have also presented an approach to obtain the minimum BER and PAPR of TC and found out the values of design parameters (a and b) for which TC scheme has minimum BER and PAPR.

Analisis Perancangan Jaringan Fiber to The Home Area Universitas Nasional Blok IV dengan Optisystem

Researchers will be designing the access network Fiber To The Home (FTTH) on the technology of Gigabit Passive Optical Network (GPON). The location that became the case study was the National University of Block IV, where the network speed at the site was slightly reduced speed. The purpose is to get the design of an access service network that is expected to be implemented for triple play services. Starting with data collection of data. The Fiber To The Home (FTTH) network design determining device specification, layout and number of devices used and simulated using Optisystem application. Then in the analysis based on predefined parameters in the form of BER (Bit Error Rate), Link Power Budget, and Rise Time Budget that meet the optical network with the standard of PT. Telkom. The results of the BER value has fulfilled the minimum BER value specified for fiber optic is 10-9 and for parameter Q – Factor obtained value 9,32288 so that has been meets the standard because it shows values above 6

Optimal Power Allocation for MIMO Underwater Wireless Optical Communication Systems Using Channel State Information at the Transmitter

For multiple-input-multiple-output underwater wireless optical communication (UWOC) systems with on-off keying modulation, we obtain the optimal power allocation policies that minimize the bit error rate (BER), subject to average power constraints. In this article, we consider a comprehensive channel model that takes into account absorption, scattering, and weak turbulence-indeed lognormal fading. The optimal power allocation policies are obtained using the perfect channel state information available at the receiver (CSIR) and transmitter (CSIT) for both MISO and MIMO systems. In the MISO UWOC link, the optimal policies result in allocating the whole available power to the optical source with highest instantaneous SNR, i.e., maximum fading coefficient. In the MIMO UWOC link, the equivalent fading coefficient of the ith optical source is defined as the sum of the fading coefficient associated with the ith optical source and other receiver apertures. In this case, the total available power should be allocated to the optical source with the highest equivalent fading coefficient to have the minimum BER. Furthermore, we analytically obtain the exact BER expressions for both MISO and MIMO systems assuming the optimal power allocation. Simulation results are further provided to verify our analytical results. The results demonstrate that MIMO techniques with optimal power allocation provide better performance compared to other alternatives such as equal power allocation.

Estimation of frequency offset prior to adaptive equalization for improved performance of DP-QPSK DWDM system

The processing of the signal in a digital coherent receiver helps to compensate for different linear and non-linear fiber impairments. In existing digital coherent receivers, adaptive equalization (AE), a slow varying phase correction process is employed prior to frequency offset estimation (FOE), which is a fast varying phase correction process. In this work, it is proposed that the fast varying correction process should be applied first because FOE can also partially remove the phase errors thereby facilitating the AE to perform better. The proposed technique is evaluated through exhaustive simulations for an eight-channel differentially encoded dual-polarization quadrature phase-shift keying (DP-QPSK) DWDM system with channel spacing of 50 GHz and spectral efficiency (SE) of 2.24 b/s/Hz. The results confirm that the proposed technique can enhance the capability of AE thereby improving the performance of the system in terms of BER. The proposed technique exhibits a characteristic under which the considered system performs with minimum BER over a wide range of launch power, which can further be traded to increase the transmission distance. The proposed technique also exhibits a lesser dependence on laser linewidth of the local oscillator (LO), to allow the use of less expensive laser sources. The proposed technique is also helpful in mitigating the effects of in-band crosstalk due to optical switches.

Minimum BER Criterion and Adaptive Moment Estimation Based Enhanced ICA for Wireless Communications

This paper concentrates on investigating an enhanced independent component analysis (ICA) method for blind separation of signals corrupted by noise in wireless communications. Because of the traditional classical ICA methods that always have an inadequate capacity of anti-noise or insufficient separable ability in noise circumstance without satisfying practical application requirements. For this reason, two mechanisms are conducted to establish the modified cost function and fulfill the optimization assignment in the process of constituting an enhanced ICA algorithm. This proposed algorithm can benefit tremendously from the derived minimum bit error rate (BER) criterion and the novel adaptive moment estimation (Adam) optimization approach. In this work, firstly, the novel cost function is obtained according to minimum BER fused into maximum likelihood (ML) principle-based ICA cost function. Furthermore, by utilizing Adam processing, the task of blind separation of mixed signals is implemented via optimizing this modified cost function. Lastly, theoretical analysis and experiment results corroborate the better effectiveness and robustness of the proposed enhanced ICA algorithm compared with a series of popular representative ICA methods.

MBER Combining for MIMO VLC With User Mobility and Imperfect CSI

Visible light communication (VLC) has emerged as a green, low-cost, and secure supplement for existing radio frequency (RF) based systems. Although promising, the performance of VLC based systems is limited by several impairments, which degrade the achievable bit error-rate (BER) performance, viz. variations in channel-gain due to user-mobility, and channel-estimation error. Hence, in this letter, the bit error rate (BER) of maximal ratio combining is quantified over a multiple-input multiple-output (MIMO) VLC system, while considering the aforementioned impairments. Next, using the derived expressions, exact and asymptotic combiners based on the minimum bit error-rate (MBER) criterion are formulated for MIMO VLC systems impaired by user-mobility, and channel-estimation error. The accuracy of the contributed expressions for BER, and the performance of the proposed MBER combiner (MBERC) are corroborated by simulations performed over realistic MIMO VLC channels. Additionally, it is found that the proposed MBERC delivers improved BER performance in presence of channel-estimation error and user-mobility, which makes the proposed methodology viable.

MBER Criterion Assisted Power NOMA Design and Performance Analysis With Estimated Channel

In this treatise, we consider a power non-orthogonal multiple access (NOMA) design based on the minimum bit error ratio (MBER) criterion. Existing literatures have shown that the MBER based works show a considerable performance improvement in terms of bit error ratio (BER) for a communication system. We have proposed to design the power coefficients for multiple users with the aid of optimized BER, which is adopted as the cost function. In this work, we have considered a transceiver system having a single-input single-output (SISO) antenna configuration with the $M$ -quadrature amplitude modulation ( $M$ -QAM) signal constellation. The optimization ensures that each user maintains a minimum rate requirement. In this work, we have extensively analyzed the BER performance due to estimated channel for any link. The numerical results demonstrate an overall BER improvement compared to the existing schemes, albeit, the scheme attracts large computational complexity. We have also proposed a variation of the MBER based optimization algorithm, which improves the BER performance. This variation is based on the splitting of the search space for the algorithm and it results in a better performance benefit. Traditionally, NOMA increases the spectral efficiency compared to its orthogonal counterpart. Nevertheless, our proposed solution will still hold this feature along with a better BER performance, though its spectral efficiency will be slightly less compared to the traditional sum-rate based power NOMA.

A Multistage High Performance Amplification Approach for Improving WDM Communication System

Abstract Optical amplifiers are developed to boost up the performance of the communication systems. Amplifiers such as erbium doped fiber amplifier (EDFA), RAMAN and semiconductor optical amplifier (SOA) are used for this purpose. It is mandatory to use optical amplifiers for signal transmission to long distances. In this paper, the hybrid optical amplifier EDFA-RAMAN-EDFA is proposed to enhance the signal quality received at receiver end and to initiate the efficient transmission of 8 × 10 Gbps transmission speed for wavelength division multiplexed (WDM) system. The proposed mechanism is evaluated with respect to various parameters such as quality factor, eye-height, and bit error rate (BER) and eye diagram considering various values of transmission distance ranging from 100 to 200 km. The analysis shows that the proposed mechanism has better quality factor value and minimum BER value than the traditional approach. Wider eye opening for proposed technique represents that the distortions produced in the system are least.

Minimization of Bit Error Rate in Polar Codes for Achieving Channel Capacity

Polar codes are designed to achieve Shannon’s theoretical limit for channel capacity with low complexity constructive approach. polar codes invented by E Arikan with the exceptional phenomenon by considering the generator matrix instead of parity bits with the information bits. As the block length N increases the sequential decoding paths are increases this may cause a reduction in SNR and increases the BER, this will occupy more channel bandwidth and consumes more power to transmit the signal. To notice the issues, we proposed a more constructive approach for error-free polar codes design up to 6 Gbps with proposed priority enabled reliability sequence (PERS), bit channels and CRC aided polar codes. This approach outperforms as compared with earlier ones.

An efficient SAC-OCDMA system using three different codes with two different detection techniques for maximum allowable users

In this paper, three codes spectral amplitude coding optical code division multiple access (SAC-OCDMA) are proposed and compared in terms of system performance including bit error rate (BER), number of active users, high achievable data rate, high signal to noise ratio (SNR) and the minimum received power that the OCDMA system supports to achieve a minimum BER value. The proposed codes are diagonal double weight (DDW) codes, modified double weight (MDW) codes and enhanced double weight (EDW). Different detection as AND subtraction detection technique and single photodiode detection (SPD) are investigated to reduce the effect of both the multiple access interference and phase induced intensity noise. The obtained results show that SAC-OCDMA using EDW code with SPD detection can achieve large number users with better BER (~ 10−9), SNR (> 20 dB), and minimum received power (~ − 20 dBm) relative to the other codes with other detection techniques.

Performance Improvement of FTTH Architecture with OCDMA Technique

In proposed simulation model, Fiber to the home (FTTH) architecture with a filter called fiber Bragg grating (FBG) based the optical code division multiple access (OCDMA) technique used to provide access to number of users to share all the bandwidth simultaneously. FTTH provides higher bandwidth than the traditional existing technology of broadband, having the capability of providing all the servixces of communication like data services, voice services and video services. The traditional metallic cables are replaced with optical fibers in Fiber to the Home to end line consumers. OCDMA provides high reliable communication. The performance improvement of FTTH architecture is done through OCDMA technique. In paper at very first, FTTH, the system with OCDMA is explained after that the architecture of FTTH using OCDMA technique, its principle explained. The proper coordination of time plays an important role in OCDMA, otherwise there is more chances of overlapping of signals and noise which may some time lead to crosstalk. There is a use of FBG as an encoder and decoder because of its low cost and the investigation is done on eye opening, BER, Q factor. The proposed model provides high Q-factor and minimum BER which is required for demands of the future communication services.

Dense Wavelength Division Multiplexing using Dispersion Fibre with Erbium Doped Fiber Amplifier

Dense wavelength division multiplexing is used in various broadband communications. It combines information from distinct sources on an optical fiber, each signal being transmitted simultaneously on its own distinct light wavelength. Radio over fibre is a hybrid system that has both fibre optic link and free space radio path. This paper aims to evaluate the performance of the system using Erbium Doped Fibre Amplifier, Single Mode Fibre and Dispersion compensating Fibre. Single beam of light is passed by the SMF and is used for long distance signal transmission. DCF is used to reduce the dispersion in the optical signal. EDFA reduces the degradation of the signal by cancelling the effect of attenuation. It is an optical repeater used to raise the intensity of the optical signal. Mach – Zehnder modulator is used for the modulation. The simulation is carried out by using optisystem software version 15.0. Various parameters like Q-factor, BER pattern, threshold, minimum BER are compared and estimated.

Transmission (2Gbps) over optical fiber cable by using radio over fiber and wavelength division multiplexing techniques

In recent years, there has been a growing and continuous demand for great (data rates) beyond existing wired and wireless networks. Radio-over-Fiber technology is considered as an efficient and practical solution for providing broadband wireless. In this paper, many techniques are used to implement a system that has the capability to provide a great bit rate, broadband bandwidth, and minimum cost. So Radio-over-Fiber technology was used to modulate the light with radio-signal and transmission the signals through an optical fiber cable. Wavelength-Division-Multiplexing technique was used to send many signals through the same link, and Subcarrier Multiplexing-Amplitude Shift keying as a modulation format. 2Gpbs separate on two channels was transmitted on Single-Mode Fiber. The average results obtained from our experience was as follows: maximum Q factor average = 4.9712925, minimum BER average = 3.63*10-7, total power average (dBm) = -51.1502, the OSNR average (dB) = 52.085 for channel_1. The results of channel_2 were: maximum Q factor average = 5.5901325, minimum BER average = 1.26*10-8, total power average (dBm) = -46.60135, the average of optical signal-to-noise ratio (dB) = 54.65. All the average result that has from our simulation was very good and acceptable. The simulation and performance test of our experience was done using Optisystem 7.0.

Performance evaluation of hybrid modulation techniques for high speed radio over fiber communication system

In Radio over Fiber (RoF) technology, the optical network capacity is integrated with the wireless network. The main objective of this work is to enhance the performance behavior of optical fiber communication system in terms of BER, Received Power and Q-Factor. The proposed combined modulation technologies, such as Pulse Amplitude Frequency Modulation (PAFM), Differential Phase Shift Keying Amplitude Modulation (DPSKA), Offset Quadrature Phase Shift Keying Amplitude Modulation (OQPSKA), Quadrature Amplitude Frequency Modulation (QAFM), Frequency Phase Modulation (FPM) and Pulse Amplitude Phase Modulation (PAPM), are used to meet this objective. The input data are used for modulating the electrical carrier signal with a frequency of 250 and 255[Formula: see text]GHz. This hybrid modulation technique obtained the minimum BER of about [Formula: see text] in FPM technique. The maximum Q-Factor of 33 is obtained in QAFM technique. The obtained maximum received power is 0.79[Formula: see text]mW in OQPSKA technique.

Comparative analysis of MIMO-based FSO and MIMO-based MGDM communications

The ever-growing need for high data rate, bandwidth efficiency, reliability, less complexity, and less power consumption in the communication systems is on the increase. Modern techniques have to be developed and put in place to meet these requirements. In the last few years, free space optical (FSO) communication systems have attracted considerable research efforts mainly due to their inherent potential transmission capacity, much higher than that offered by radio transmission technologies. However, despite of great potential of FSO communication, its performance is limited by the adverse effects (viz., absorption, scattering, and turbulence) of the atmospheric channel. Different studies on weather conditions and techniques employed to mitigate their effect are studied. On other hand, a MMF network may constitute the backbone network that feeds fixed-wired services (e.g. voice telephony) as well as wireless services (e.g. IEEE 802.x) throughout the building. The large bandwidth makes MMF a very attractive medium for low-cost broadband in building networks, in which several independent sets of services are integrated. In addition, research has shown that compared to conventional single-input single-output (SISO) systems, multiple-input multiple-output (MIMO) can actually increase the data rate of a communication system, without actually requiring more transmit power or bandwidth. In this paper, we develop a comparison between MIMO over multimode fiber (MMF) using MGDM and MIMO based FSO links. The achievable performance improvements, including received power levels, bit error rate (BER), and quality factor (Q-factor) are presented. Numerical results are obtained for single-input single-output (SISO) as well as for multiple-input multiple-output (MIMO) configurations. Simulation results show that MMF outperforms FSO links in terms of max Q-factor, minimum BER, and eye diagram. Seen that the dependence of the FSO system performance on the weather conditions is one of the most significant FSO limitations, we analyze the performance of FSO under clear, haze, and fog conditions using Q-factor, bit error rate (BER), etc., at varied distances. From the results, it can be concluded that as we move from clear weather conditions to haze and fog weather conditions, Q-factor of the received signal decreases.