Noise Transfer Research Articles

Theoretical investigation of new composite based on metamaterial able to strongly attenuate heat and noise propagation for civil engineering

New design in civil engineering need reduction of cost of material. Engineers and researcher are focused on material parameter to improve proposed alternatives. In this work we are developed theoretical tool based on finite element method to evaluate transmission noise and heat transfer along composite wall for civil engineering. In this work, composite based metamaterial is used for wall elaboration. At first Time noise level in broad band high frequency level was extracted using frequency acoustic finite element method, and using advection, diffusion model heat transfer distribution was also extracted. Finally, combination of constitutive model with metaheuristic optimization enabled us optimal parameters of the material composite, for specific condition. Constitutive resulted and discussion will have detailed in the paper. Keywords: frequency acoustic analysis, advection diffusion, genetic algorithm, civil engineering, material science, metamaterial

Readout circuit noise analysis and low-noise design for piezoelectric micro-machined ultrasonic transducers with large parasitic capacitance.

Readout circuits are fundamental components in many application systems that utilize piezoelectric micro-machined ultrasonic transducers (pMUTs). This study models the noise and signal transfer functions of trans-impedance amplifiers (TIAs), charge-sensitive circuits, and voltage-mode readout circuits in detail. A series of simulations and experiments were conducted to elucidate the advantages and disadvantages of these circuit types. Both theoretical and experimental results indicate that the intrinsic capacitance of large pMUTs can significantly degrade the quality of the readout signal. Furthermore, while the TIA-based readout circuit demonstrates clear gain advantages, it is also susceptible to considerable noise interference. This work proposes an improved readout circuit design that effectively mitigates noise interference while preserving the gain advantages of the TIA architecture. The implemented prototype circuit successfully reduces the noise from 73 mVp-p to 13 mVp-p.

An Anti-Forensics Video Forgery Detection Method Based on Noise Transfer Matrix Analysis.

The dispute over the authenticity of video has become a hot topic in judicial practice in recent years. Despite detection methods being updated rapidly, methods for determining authenticity have limitations, especially against high-level forgery. Deleting the integral group of pictures (GOP) length in static scenes could remove key information in the video, leading to unjust sentencing. Anyone can conduct such an operation using publicly available software, thus escaping state-of-the-art detection methods. In this paper, we propose a detection method based on noise transfer matrix analysis. A pyramid structure and a weight learning module are adopted to improve the detection rate and reduce the false positive rate. In total, 80 videos were examined through delicate anti-forensic forgery operations to verify the detection performance of the proposed method and three previously reported methods against anti-forensic forgery operations. In addition, two of the latest learning-based methods were included in our experiments to evaluate the proposed method. The experimental results show that the proposed method significantly improves the detection of frame deletion points compared with traditional and learning-based methods, especially in low false positive rate (FPR) intervals, which is meaningful in forensic science.

Supervised Factor Analysis Transfer: Calibration transfer with noise modeling and response variable integration

Multivariate calibration models often encounter challenges in extrapolating beyond the calibration instruments due to variations in hardware configurations, signal processing algorithms, or environmental conditions. Calibration transfer techniques have been developed to mitigate this issue. In this study, we introduce a novel methodology known as Supervised Factor Analysis Transfer (SFAT) aimed at achieving robust and interpretable calibration transfer. SFAT operates from a probabilistic framework and integrates response variables into its transfer process to effectively align data from the target instrument to that of the source instrument. Within the SFAT model, the data from the source instrument, the target instrument, and the response variables are collectively projected onto a shared set of latent variables. These latent variables serve as the conduit for information transfer between the three distinct domains, thereby facilitating effective spectra transfer. Moreover, SFAT explicitly models the noise variances associated with each variable, thereby minimizing the transfer of non-informative noise. Furthermore, we provide empirical evidence showcasing the efficacy of SFAT across three real-world datasets, demonstrating its superior performance in calibration transfer scenarios.

Power Over Fiber and Analog Radio Over Fiber Simultaneous Transmission Over Long Distance in Single Mode, Multicore, and Hollow Core Fibers

AbstractIn this work, a novel study of the feasibility of shared Power over Fiber (PoF) and Fifth‐Generation (5G) New Radio (NR) Analog Radio over Fiber (ARoF) over long distance Hollow‐core Fibers (HCF) is presented. Comparative measurements between similar lengths of HCFs, Multicore (MCF) and Single Mode Fibers (SMF) are performed. A complete analysis on the Stimulated Raman Scattering (SRS)‐induced noise transfer from PoF to ARoF is tackled. Relative Intensity Noise (RIN) of ARoF signals is measured for all the optical fibers tested, observing no degradation in HCFs, neither on MCFs and significant deterioration in SMFs. A combination of PoF and 5G NR ARoF link in a single fiber is implemented, and 5G NR signals with different modulation formats are successfully transmitted through HCFs and MCFs without degradation, while SRS‐induced noise transfer in SMFs massively deteriorate them. PoF transmission efficiencies are also analyzed, achieving up to 9.9 % System Energy Efficiency (SEE) for a 3.1 km HCF, 0.9 % for a 11.1 km HCF and 1.5 %, 13.5 %, and 20.4 % in a 10 km MCF, a 9.8 km SMF and a 3.3 km SMF, respectively. The PoF signal is used to supply a Bluetooth Low‐Energy (BLE) load with a power consumption of 20 mW.

Impact of pump-phase noise in PPLN-based optical parametric amplifier and wavelength converter for digital coherent transmission

Wideband signal amplification and optical signal processing with a high gain using an optical parametric amplifier based on a periodically poled LiNbO3 (PPLN) waveguide is attractive for constructing wideband optical fiber networks. We experimentally investigate the transfer characteristics of the phase noise of a pump laser in χ(2)-based optical parametric amplification and wavelength conversion on the basis of second-harmonic-generation and differential-frequency-generation processes. We also evaluate the effect of the transferred phase noise on signal quality in dispersion-unmanaged digital coherent fiber transmission systems. We show that the phase noise is transferred only to the wavelength-converted idler and does not affect the amplified signal even by using a pump laser with a MHz-order linewidth. We also show that the phase noise transferred to the idler light can have a similar impact on signal quality as equalization-enhanced phase noise (EEPN) in digital coherent transmission. The signal penalty including EEPN was evaluated with several pump lasers and at symbol rates of 32, 64, and 96 Gbaud. We also propose a method of using correlated pump lights between a wavelength converter pair to cancel out the transfer of phase noise.

A First-Order Noise-Shaping SAR ADC with PVT-Insensitive Closed-Loop Dynamic Amplifier and Two CDACs

This paper presents a first-order noise-shaping (NS) successive approximation register (SAR) analog-to-digital converter (ADC) with a process, (supply) voltage, and temperature (PVT)-insensitive closed-loop integrator and data-weighted averaging (DWA). The use of a cascode floating inverter amplifier (FIA)-type dynamic amplifier with high gain enables an aggressive noise transfer function while minimizing the power consumption associated with the use of an active filter. In the proposed ADC, the residue is generated by a capacitive digital-to-analog converter (CDAC) employing DWA, which is made possible by employing a second CDAC, which operates after the SAR operation is completed. The proposed ADC is designed with a 28 nm CMOS process with 1 V power supply. The simulation results show that the ADC achieves the SNDR of 71.2 dB and power consumption of 228 μW when operated with a sampling rate of 80 MS/s and oversampling ratio (OSR) of 10. The Schreier figure-of-merit (FoM) is 173.6 dB, and Walden FoM is 9.6 fJ/conversion-step.

The evaluation for plasma noise in arbitrary time-delay interferometry combinations

The laser interferometer space antenna (LISA) uses laser interferometry to measure gravitational wave-induced distance changes between freely falling test masses on separate spacecraft. In practice, the space-borne gravitational wave detector operates in a plasma medium, and subsequently, the variations in electron density affect the refractive index and add displacement noise to measurements. Geometric time-delay interferometry (TDI) is the TDI combinations searched by geometric method, which is employed to mitigate overwhelming laser phase noise. This study explores all forty-five second-generation geometric TDI combinations up to sixteen links, analyzing plasma noise effects via power spectral density and cross-spectral density calculations for different optical links. Our findings reveal that plasma noise can exceed the noise floor, which comprises optical metrology system and test mass acceleration noise, in certain low-frequency regions due to different noise transfer behaviors. Further, we establish electron density requirements for various TDI combinations, showing that densities below 100cm−3/Hz @ 10mHz satisfy LISA’s criteria across all forty-five combinations. This allows for optimized TDI selection based on specific plasma densities.

NegVSR: Augmenting Negatives for Generalized Noise Modeling in Real-world Video Super-Resolution

The capability of video super-resolution (VSR) to synthesize high-resolution (HR) video from ideal datasets has been demonstrated in many works. However, applying the VSR model to real-world video with unknown and complex degradation remains a challenging task. First, existing degradation metrics in most VSR methods are not able to effectively simulate real-world noise and blur. On the contrary, simple combinations of classical degradation are used for real-world noise modeling, which led to the VSR model often being violated by out-of-distribution noise. Second, many SR models focus on noise simulation and transfer. Nevertheless, the sampled noise is monotonous and limited. To address the aforementioned problems, we propose a Negatives augmentation strategy for generalized noise modeling in Video Super-Resolution (NegVSR) task. Specifically, we first propose sequential noise generation toward real-world data to extract practical noise sequences. Then, the degeneration domain is widely expanded by negative augmentation to build up various yet challenging real-world noise sets. We further propose the augmented negative guidance loss to learn robust features among augmented negatives effectively. Extensive experiments on real-world datasets (e.g., VideoLQ and FLIR) show that our method outperforms state-of-the-art methods with clear margins, especially in visual quality. Project page is available at: https://negvsr.github.io/.

Lab to Multiscene Generalization for Non-Line-of-Sight Identification With Small-Scale Datasets

Ultra-wideband (UWB) wireless indoor positioning systems rely on time of flight (TOF) to estimate distances but can be biased and miscalculated due to non-line-of-sight (NLOS) transmission channels in complex environments. Therefore, to remove errors, several machine learning techniques have been proposed for identifying NLOS signals from Channel Impulse Responses (CIRs). However, as CIR signals could be heavily influenced by various environments, current NLOS classifiers are not universal to provide satisfactory accuracy for new scenarios and require detailed measurements on a large number of CIRs for training. Hence, we propose a generalization method based on data augmentation via noise injection and transfer learning to allow the deep neural network (DNN) trained under a lab condition to be applied to various and even harsh practical scenarios with the need to measure massive training data minimized. This paper presents the first demonstration that it is effective to utilize a lab-based pre-trained DNN for real-world transfer and white Gaussian noise data augmentation for ML-based NLOS identification on UWB CIRs to address the problem when it is not feasible to measure sufficient training data. Our testing results show that in two scenarios, corridor and parking lot, with only 50 CIR signals as the training set, the accuracy of the NLOS identification model after applying the proposed method is increased from 84.4% to 98.8% and from 81.1% to 97.1%, respectively.

Experimental validation on structure-borne underwater radiated noise transfer function analysis for marine structure

In this paper, an experimental validation of a numerical procedure for estimating the structure-borne Underwater Radiated Noise (URN) Transfer Function (TF) of a marine structure based on the SEA theory has been performed. For the purpose, the structure-borne URN TF of a central point-excited one-side fluid-loaded four-edge stiffened plate in a reverberant water tank has been measured and compared with the SEA result. Additionally, the practical applicability of the procedure for a real ship structure has been demonstrated by comparing the URN analysis result based on the transfer function method and the measurement result for a Korean research vessel, ‘Cheong-Hae’. From the results, it is confirmed that the presented procedure can be used to estimate the structure-borne URN level emitted from the vibrating fluid-loaded side shells of a ship structure.

A Multi-Phase Phase-Generated Carrier Demodulation Algorithm for Stability Improvement of Noise Transfer Coefficient for Fiber Optic Hydrophone

A Multi-Phase Phase-Generated Carrier Demodulation Algorithm for Stability Improvement of Noise Transfer Coefficient for Fiber Optic Hydrophone

A novel two-stream multi-head self-attention convolutional neural network for bearing fault diagnosis

Bearing is one of the most prone to failure components, and the most commonly used supporting parts in rotating machinery. There are important economic and safety significance for studying effective bearing fault diagnosis method. Deep learning has been widely applied to intelligent fault diagnosis of rotating machines. In particular, convolutional neural network (CNN) improves diagnostic accuracy due to automatic feature extraction ability. However, CNN cannot fully use the temporal information of the input signals and extract global features. This article presents a new depth model called two-stream multi-head self-attention convolutional neural network (TSMSCNN) for bearing fault diagnosis to solve the above problems. First, we obtain temporal information through the difference of data points in the input signal. Next, the temporal information and original signal are used as input for two CNN branches. Then, the multi-head self-attention (MS) mechanism adaptively aggregates the features and assigns weights to the features extracted by CNN. Finally, the learned high-level representations are fed into the full connect (FC) layer for fault diagnosis. Experimental results prove that the proposed TSMSCNN has higher accuracy than state-of-the-art methods and has excellent noise immunity and transfer performance.

Nonlinear dynamics of relative intensity noise transfer at fiber amplification and supercontinuum generation

Supercontinuum sources via femtosecond pumping in highly nonlinear photonic crystal fibers considerably impact scientific research and industrial applications. Herein, we investigate the complex transfer function of relative intensity noise in a broadband fiber supercontinuum source generated using an ytterbium-doped mode-locked laser. A designed intensity noise was artificially added to the system through the introduction of weak sinusoidal intensity modulation to the seed pulses. Owing to the influence of nonlinear gain dynamics and soliton dynamics during power amplification and spectral broadening, the transfer functions exhibit unique frequency and wavelength dependencies. Systematic measurements indicate that the seed transfer functions exhibit the characteristics of damped high-pass filters and saturate at low Fourier frequencies within the fiber amplifier. Moreover, supercontinuum broadening induces a nonlinear transformation of fluctuations, resulting in considerable amplification and negative correlation within the dispersion wave and soliton self-frequency shift regions. Clarifying the mechanism and bandwidth of this system is imperative to achieving low-noise supercontinuum generation because they provide insights into the nonlinear laser dynamics associated with broadband spectral broadening and noise transformation.

Coherent optical frequency transfer via 972-km fiber link

We demonstrate coherent optical frequency dissemination over a distance of 972 km by cascading two spans where the phase noise is passively compensated for. Instead of employing a phase discriminator and a phase locking loop in the conventional active phase control scheme, the passive phase noise cancellation is realized by feeding double-trip beat-note frequency to the driver of the acoustic optical modulator at the local site. This passive scheme exhibits fine robustness and reliability, making it suitable for long-distance and noisy fiber links. An optical regeneration station is used in the link for signal amplification and cascaded transmission. The phase noise cancellation and transfer instability of the 972-km link is investigated, and transfer instability of 1.1 × 10−19 at 104 s is achieved. This work provides a promising method for realizing optical frequency distribution over thousands of kilometers by using fiber links.

Enhancing the transferability of adversarial samples with random noise techniques

Deep neural networks have achieved remarkable success in the field of computer vision. However, they are susceptible to adversarial attacks. The transferability of adversarial samples has made practical black-box attacks feasible, underscoring the importance of research on transferability. Existing work indicates that adversarial samples tend to overfit to the source model, getting trapped in local optima, thereby reducing the transferability of adversarial samples. To address this issue, we propose the Random Noise Transfer Attack (RNTA) to search for adversarial samples in a larger data distribution, seeking the global optimum. Specifically, we suggest injecting multiple random noise perturbations into the sample before each iteration of sample optimization, effectively exploring the decision boundary within an extended data distribution space. By aggregating gradients, we identify a better global optimum, mitigating the issue of overfitting to the source model. Through extensive experiments on the large-scale visual classification task on ImageNet, we demonstrate that our method increases the success rate of momentum-based attacks by an average of 20.1%. Furthermore, our approach can be combined with existing attack methods, achieving a success rate of 94.3%, which highlights the insecurity of current models and defense mechanisms.

An Averaging Method for Phase Noise Studies of Quartz Phononic Frequency Combs.

A fast and accurate averaging method was derived and developed for the analysis and design of quartz phononic frequency combs. The phononic frequency combs were obtained from a pair of coupled nonlinear Duffing equations for quartz resonators by solving the equations in the time domain and performing a fast Fourier transformation (FFT) of the steady-state vibrations of the time series. Noise simulations were added to the drive frequency to study noise transfer characteristics between the drive signal and the resonances of the phononic frequency combs produced in 100-MHz quartz shear-mode resonators. Our new method averaged out the carrier frequency, thus allowing for a fast and efficient computation at parts per million accuracies of noise close to the carrier ( ∼ 10 Hz). The goal of our study was to develop methods and resonator requirements for engineering the properties of the phononic frequency combs for low-noise clock applications.

A 3.07 mW 30 MHz-BW 73.2 dB-SNDR Time- Interleaved Noise-Shaping SAR ADC With Self-Coupling Second-Order Error-Feedforward

A noise-shaping successive approximation register (NS-SAR) ADC combines the merits of the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Delta $</tex-math> </inline-formula> - <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\Sigma $</tex-math> </inline-formula> and SAR ADC, transforming it into an emerging ADC architecture to reach high resolution with good power efficiency. The single-channel NS-SAR with high resolution, however, suffers from bandwidth (BW) limitations. The time-interleaved (TI) NS-SAR mitigates the speed bottleneck but faces challenges in obtaining high resolution and BW simultaneously due to the lack of a sharp noise transfer function (NTF). This article presents a calibration-free two-channel TI-NS-SAR with an aggressive second-order NTF for high resolution. Based on a one-time error feedback (FB) at midway, we propose a second-order error-feedforward (FF) to enhance the noise-shaping (NS) effect further meanwhile avoiding the excessive NTF peaking and dynamic range (DR) loss. A dynamic residue amplifier shared between two channels lowers the offset, which reduces the redundant bit to only one bit, thus improving the efficiency of SAR conversion. Fabricated in a 28 nm CMOS with 1 V supply, the prototype achieves 73.2 dB-signal-to-noise-and-distortion-ratio (SNDR) over 30 MHz-BW when operating at 330 MHz. It consumes 3.07 mW and exhibits a Schreier FoM (FoMs) of 173.1 dB.

An intermediate frequency reconfigurable bandpass noise‐shaping SAR ADC for IoT and mobile application

AbstractThis letter proposes a reconfigurable bandpass noise‐shaping successive approximation register analog‐to‐digital converter (ADC) with a cascade of integrators with feedforward (CIFF) structure. Unlike conventional CIFF structures that use a passive feedforward path, the new design incorporates an amplifier within the filter, providing effective bandpass noise transfer function regardless of passband location, and facilitating the use of a unity gain 2‐input comparator for low noise and high stability. The loop filter includes amplification by a low power Gm‐R amplifier and two‐step charge sharing. The proposed ADC supports three different intermediate frequencies (IFs), and 12‐bit resolution is achieved for all IFs in a 28‐nm complementary metal‐oxide‐semiconductor (CMOS) process.

High-speed digital-to-analogue converters phase noise modelling

The paper presents a mathematical model of the phase noise power spectral density of a high-speed digital-to-analogue converter. The shapes of the envelopes of the spectrum of the output signal in RFZ3, RFZ4 operating modes are given. The phase noise transfer coefficients for RFZ3, RFZ4 operating modes are obtained. The modelling of the power spectral density of phase noises in the studied operating modes was carried out. The analysis of the received dependences is carried out. It is concluded that RFZ3, RFZ4 modes of operation allow to obtain a lower level of PSD phase noise for images n = 1, 3, 4, 5, which indicates the possibility of generating high-frequency signals with a frequency that is 5-11 times higher than the generated frequency in NRZ mode without noise degradation.