BER Estimation Research Articles

A systematic PAPR analysis of optical 5G waveforms using advanced and deep learning PAPR algorithms: estimation of PAPR, PSD, and BER

A systematic PAPR analysis of optical 5G waveforms using advanced and deep learning PAPR algorithms: estimation of PAPR, PSD, and BER

BER estimation for STBC-MC-DS-CDMA-4 antennas system by varied wavelet-carriers features via AWGN-flat channels

BER estimation for STBC-MC-DS-CDMA-4 antennas system by varied wavelet-carriers features via AWGN-flat channels

Remote photoplethysmography-based human vital sign prediction using cyclical algorithm.

This article aims to predict vital signs like heart rate (HR), respiration rate, and arterial oxygen saturation using ambient light video, eliminating chronic distortions through improved frame quality with BER estimation. The study employs the cascade residual CNN-FPNR technique for preprocessing and SNR enhancement using energy variance maximization. The image cascade network (ICNet) facilitates segmentation, achieving strong segmentation in low-light ambient videos. Remote photoplethysmography (iPPG) enables noncontact vital sign monitoring, predicting HR and respiratory rate (RR). An innovative noninvasive temperature and cyclical algorithm, incorporating principal component analysis and fast Fourier transform, evaluate patient HR and RR. To address challenges related to involuntary movements, a dynamic time-warping-based optimization method is used for precise region selection. The study introduces an intensity variance-based threshold analysis for arterial oxygen saturation level determination. Ultimately, the support vector machine (SVM) classification technique evaluates the ground truth, showcasing the system's promising potential for remote and accurate vital sign assessment.

Outage Probability and BER Estimation for FSO Links with Truncated Normal Time Jitter and Longitudinal Gaussian Pulse Propagation in Dispersive Media

FSO is one of the most widespread, low-cost, wireless, optical communicational technologies with sufficiently high throughput, transmission reliability, and high-level security. Nevertheless, many fading effects act on the optical pulses used, during their propagation, causing performance degradation. In this work, group velocity dispersion and time jitter, modeled by the truncated normal distribution, are jointly investigated analytically and numerically. The availability of the studied model is expressed in terms of outage probability, while its reliability is given in terms of its average bit error rate, through the derived novel mathematical expressions. To the best of authors’ knowledge, this is the first time that the outage and the BER performance are estimated analytically, through specific approximations, taking into account the abovementioned physical effects. Furthermore, using the obtained mathematical forms, the corresponding numerical results are presented by assuming typical parameter values for realistic FSO links.

On the performance of companding techniques for DMT optical links

In this paper the performance of Discrete Multi-Tone (DMT) optical links using nonlinear companding schemes for peak-to-average power ratio (PAPR) reduction is investigated. First, it is developed an analytical expression to evaluate the total distortion at the demodulation stage introduced by the expansion process, and also to estimate the BER vs. SNR performance curves for companded DMT systems. The analytical expression and procedure for BER estimation is tested with three compressing functions: μ-Law, Erf and Trapezoidal. The obtained results show a very good agreement between simulations and predictions, validating this simple, quick and accurate BER estimation tool for the considered system. Next, the effects produced by a nonlinear laser diode (modeled as a lower hard limiter) that is directly modulated, are investigated in terms of its input back-off (IBO). A trade-off between the distance that can be reached in an optical fiber link and the allowed BER degradation is numerically demonstrated. These results are compared against a nonlinear amplifier model (soft limiter), which results in a slight improvement in performance. Finally, it is shown that even though companding schemes degrade the BER for nearly linear operation, they can improve the BER performance of a DMT link if a moderate back-off value is allowed (particularly for an IBO=7 dB when the SNR>20 dB for a system with an Erf companding).

Multi-hop DF relayed FSO links with various modulation formats emulated by a dual-hop scheme for strong turbulence conditions

In this work, we try to minimize the mathematical complexity in analyzing outage and error performance by emulating multi-hop terrestrial FSO communication system as a single dual-hop scheme. More specifically, we approximate the topology of such a system and we estimate analytically its performance, by taking into account various modulation formats for strong and saturated atmospheric turbulence conditions. The theoretical study of the FSO system performance is performed using either the negative exponential or the K distribution models, while the well-known modulation formats on-off keying (OOK), pulse amplitude modulation (PAM) and pulse position modulation (PPM), have been employed. Thus, closed form mathematical expressions for outage probability and average BER estimation are derived and their outcomes can easily be used for the design of modern optical wireless links. Finally, using the obtained mathematical forms, the corresponding numerical results are presented using realistic FSO parameter values.

On the performance of optical wireless communication links impaired by time jitter, M-turbulence and pointing errors

The interest for the optical wireless communication systems increases significantly the last years due to the very high advantages of this technology. More specifically, the FSO links can achieve very high data rate and secure communications with low installation and operational cost. However, the main disadvantage of the FSO links is that their performance is dominated by the weather conditions and the turbulence of the atmosphere, where the optical beam propagates. The atmospheric turbulence mitigates significantly the performance of the FSO links and causes the scintillation effect, which results in rapid irradiance fluctuations at the receivers. Furthermore, another factor which increases the influence of the atmospheric turbulence and causes further fast changes at the receivers’ irradianceis the pointing errors. Additionally, the performance of most of the high data rate communication systems, is reduced by the time jitter effect, which causes the detection of each digital pulse before or later than the ideal time spot. Thus, in this work, the performance of a terrestrial FSO link is investigated, for first time under the simultaneous action of the M(alaga) atmospheric turbulence, the pointing errors and the time jitter effects for various, commonly used in FSO links, modulation schemes. Taking into account their joint influence, new accurate closed form mathematical expressions are derived for the average BER estimation. Finally, the corresponding numerical results and conclusions are shown and derived.

Space Time Trellis Code Frequency Index Modulation with Neuro-LS Channel Estimation in OFDM

In wireless communication, orthogonal frequency division multiplexing (OFDM) plays a major role because of its high transmission rate. In space-time shift keying (STSK), the information is conveyed by both the spatial and time dimensions, which can be used to strike a trade-off between the diversity and multiplexing gains. On the other hand, orthogonal frequency division multiplexing (OFDM) relying on index modulation (IM) conveys information not only by the conventional signal constellations as in classical OFDM, but also by the indices of the subcarriers. In this paper compressed sensing(CS) is studied in order to increase throughput and bit-error performance by transmitting extra information bits in each subcarrier block as well as to decrease the complexity of the detector. In this paper, soft trellis decoding algorithm is implemented with channel estimation using Neuro-LS technique. The result analysis shows the better performance of trellis decoder with respect to BER and Neuro-LS channel estimation with respect to BER.

Spatial diversity for QAM OFDM RoFSO links with nonzero boresight pointing errors over atmospheric turbulence channels

ABSTRACTRadio-on-free-space-optical (RoFSO) communication systems have attracted a lot of technological interest in the last few years, due to their high performance characteristics with relatively low installation and operational cost. At the same time a lot of research has been carried out on them. This specific technique facilitates the transmission of radio frequency signals with the aid of optical carriers through the atmosphere; its effectiveness is already known from the Radio over Fibre (RoF) links. However, besides their advantages, the performance of free-space optical (FSO) communication links depends strongly on the atmospheric conditions, due to the fact that the propagation path is the atmosphere. In the present work, we consider the transmission of OFDM radio signals, with QAM modulation format, through an FSO link, using spatial diversity of the receivers. For the estimation of the system performance the atmospheric turbulence effect has been modelled by the gamma-gamma distribution, the accuracy of which spans from weak to strong turbulence conditions. Furthermore, the pointing errors effect is studied with the aid of a new generalized distribution that takes account the nonzero boresight displacement of the optical beam from the optical receiver centre. In addition, different spatial jitters are taken into consideration for the two vertical axes of the receiver. Thus, accurate mathematical expressions are extracted, which lead to the estimation of the average BER and the outage probability of a spatially diverse QAM OFDM RoFSO link. Finally, the theoretical results obtained from the derived expressions are verified through the corresponding numerical simulations which are presented at the numerical results section of the manuscript.

Analysis and Design of Adaptive OCDMA Passive Optical Networks

OCDMA systems can support multiple classes of service by differentiating code parameters, power level and diversity order. In this paper, we analyze BER performance of a multi-class 1D/2D OCDMA system and propose a new approximation method that can be used to generate accurate estimation of system BER using a simple mathematical form. The proposed approximation provides insight into proper system level analysis, system level design and sensitivity of system performance to the factors such as code parameters, power level and diversity order. Considering code design, code cardinality and system performance constraints, two design problems are defined and their optimal solutions are provided. We then propose an adaptive OCDMA-PON that adaptively shares unused resources of inactive users among active ones to improve upstream system performance. Using the approximated BER expression and defined design problems, two adaptive code allocation algorithms for the adaptive OCDMA-PON are presented and their performances are evaluated by simulation. Simulation results show that the adaptive code allocation algorithms can increase average transmission rate or decrease average optical power consumption of ONUs for dynamic traffic patterns. According to the simulation results, for an adaptive OCDMA-PON with BER value of 1e-7 and user activity probability of 0.5, transmission rate (optical power consumption) can be increased (decreased) by a factor of 2.25 (0.27) compared to fixed code assignment.

Channel Capacity and BER Estimation of Indoor Optical Wireless Communication System Under Receiver Mobility

Abstract The existing radio frequency technologies face the bandwidth limitation due to the increase in the number of devices being used inside the indoor environment. though, the backbone networks are capable of carrying a large amount of data to the tune of several hundreds of gigabits per second, the last mile techniques, especially the indoor connectivity, continue to pose a challenge in terms of handling large data capacity. The indoor optical wireless communication could be one such promising technology that is potentially capable of handling large amount of data transmission within the indoor environment. The receiver mobility may largely affect the key communication parameters which undergo spatial variations. Therefore, in this paper, we investigate several parameters especially the channel capacity, bit error rate, received pulse power, pulse delay spread and signal-to-noise ratio pertaining to receiver mobility.

Design and Analysis of 25 and 35 Gbps Optical Communication System based on APDCDM Technique

and 35 Gbps Absolute Pole Duty cycle division multiplexing (APDCDM) based communication system is designed successfully. A technique for estimation of BER is developed for four users APDCDM based optical communication system, referring to the data recovery rules. The performance parameters like SNR, Q-factor and BER are calculated for the transmission rate

Multi-Level Pseudo Random Sequence Generation for Coherent Optical Transmission Systems

Coherent optical transmission systems use multiple-bits-per-symbol for improving spectral efficiencies and hence data rates. However, standards for generating test sequences for evaluating these systems do not exist and delay-decorrelated binary sequences are commonly used. These sequences may not result in the worst case symbol sequences, which can lead to incorrect BER estimation. Here we propose a method for evaluating these sequences and show an approach that can standardize these sequences using the rank of the matrix generating them.

On BER assessment of conventional- and wavelet-OFDM over AWGN channel

Orthogonal wavelets enclose more potential of dropping the ISI- and ICI-sway amid the carriers due to multipath propagation over the free-space fading channels. Moreover, wavelet-OFDM is more bandwidth efficient as compared to conventional OFDM and is less affected by Doppler shift. Accordingly, a BER estimation of discrete Fourier transform (DFT) based OFDM system and discrete wavelet transform (DWT) based OFDM system is carried out in this work. The assessment is demonstrated by means of diverse modulation schemes explicitly BPSK, QPSK, 8-PSK, QAM, 8-QAM, 16-QAM for both conventional- and wavelet-OFDM wireless system over AWGN channels. Higher orders of PSK schemes involve more SNR requirement to target an acceptable BER of 10−5 over AWGN channels in both the cases. Furthermore, the efficiency of W-OFDM increases with decreasing the required value of BER.

BER estimation for multi-hop RoFSO QAM or PSK OFDM communication systems over gamma gamma or exponentially modeled turbulence channels

Abstract The optical wireless and in particular the radio-on-free-space-optical (RoFSO) communication systems are gaining popularity due to their high date rates, license free spectrum and adequate reliability at installation and operational costs which are much lower than comparable technologies. One significant disadvantage of these systems concerns the randomly time varying characteristics of the propagation path mainly caused by the atmospheric turbulence. In this work, we study the BER performance of a multi-hop RoFSO system which is using an orthogonal frequency division multiplexing (OFDM) scheme, with either quadrature amplitude modulation (QAM) or phase shift keying format (PSK), over atmospheric turbulence channels modeled with the gamma gamma or the negative exponential distribution. The individual RoFSO parts of the whole optical link are connected to each other by using regenerators relay nodes. The dominant impairments which are the most significant and have been taken into account are the atmospheric turbulence, the path losses, the nonlinear responsivity of the laser diode and the inter-modulation distortion effect. For this setup, we derive closed form mathematical expressions for the estimation of the BER performance for each individual OFDM RoFSO link and for the whole relayed optical communication system, as well. Finally, the corresponding numerical results, for common link׳s parameters, are presented.

Study on the efficiency of Eb/No algorithm for BER estimation over 112-Gb/s PDM CO-OFDM system with QPSK mapping

We research an efficient BER estimation method for 112-Gb/s polarization division multiplexing coherent optical OFDM (PDM CO-OFDM) with QPSK mapping over 800km SSMF based on Eb/No algorithm in this paper. We first lay out the related formulas’ derivation to set up the theoretical basis for the feasibility of Eb/No algorithm and then we implement a series of simulations to illustrate the relationship of BER (and Q factor) versus OSNR, launch power of transmitter, chromatic dispersion and nonlinearity in optical fiber link via both Eb/No algorithm and Monte Carlo algorithm. The simulations demonstrate that BER estimated by Eb/No algorithm can achieve a precision up to 10−16 just with 105 bits while Monte Carlo algorithm needs at least 1018 bits to get the same level. Therefore, Eb/No allows a quick and reliable method for BER estimation instead of the time consuming Monte Carlo method, which can be used to support simulations with various conditions.

Influence of fiber link impairments to Eb/No estimation in CO-OFDM systems with QPSK mapping

BER estimation method by Eb/No for CO-OFDM systems with QPSK mapping is studied in this paper. The relationships of BER vs. OSNR and Q factor vs. OSNR are firstly represented in detail. The comparisons between BER estimation by Eb/No and Monte-Carlo (MC) method with OSNR, chromatic dispersion (CD), laser linewidth and fiber nonlinearity impairments are also researched in this paper. Through simulation in 40Gb/s CO-OFDM systems with those impairments, BER based on Eb/No can estimate accurately 10−16 levels justly using 105 bits, while MC required at least 1018 bits in comparison. Eb/No is creditable and offers an alternative to the time-consuming MC method.

A Fully Integrated, 290 pJ/bit UWB Dual-Mode Transceiver for cm-Range Wireless Interconnects

We present an ultra-wideband transceiver designed for ultra-low-power communication at sub-10 cm range. The transceiver operates at a 5.6 GHz carrier frequency, chosen to minimize path loss when using a 1 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> antenna, and can switch its architecture between self-synchronous rectification and low-IF to adapt its power consumption to the channel characteristic in real time. A low-power digital circuit exploits redundancy in the modulation scheme to provide a real-time BER estimate used to close the mode-switching loop. Implemented in 65 nm CMOS, the transceiver consumes 25 μW when transmitting and 245 μW when receiving in low-power mode, plus 45 μW in the clock generator, and only requires an external antenna. Dual-mode operation allows range extension and mitigates interference.

Virtual RF system platform dedicated to heterogeneous complex SoC design

In this paper, we propose to develop a hierarchical library associated with various simulators that can be used in a single platform, called TrustMe-ViP, which enables a unique simulation framework and full model interoperability. Such platform is dedicated to complex SoC design, such as trusted personal devices where cost and time-to-market are very important constraints. To validate this methodology, we present the estimation of BER and power consumption for a Bluetooth transceiver.

QBER Estimation in QKD Systems With Polarization Encoding

A model for quantum BER estimation in polarization encoded quantum key distribution systems is presented. Both TDM and WDM based polarization control schemes are analyzed. It is shown that TDM presents some important advantages when compared with the WDM control scheme. In WDM, the polarization decorrelation between the reference and data signals is an intrinsic and very limitative impairment. This effect has a contribution to quantum BER that increases with the propagation distance, and is highly dependent on the fiber polarization mode dispersion. In the TDM control scheme, the polarization decorrelation is less critical and other issues, like the single photon detector and feedback polarization control system performance tend to dominate. We show that for long distances the fiber losses represent the main contribution to the total quantum BER. Nevertheless, for distances shorter than 70 km and frequencies higher than 5 MHz the after pulse detections provide an important contribution to the total quantum BER.