Glitch Noise Research Articles

SGCS: a signal reconstruction method based on Savitzky-Golaysgz filtering and compressed sensing for wavelength modulation spectroscopy.

The residual oxygen concentration in pharmaceutical glass vial variously threatens the aseptic properties of encapsulated agents. The demodulated 2nd harmonic signals in the wavelength modulation spectroscopy (WMS) detection system, the data basis of the inversion of oxygen concentration, are inevitably destroyed by various time-varying industrial noises. In this work, we propose a signal reconstruction method based on self-correcting Savitzky-Golaysgz filter and compressed sensing (namely SGCS) for the urgent signal denoising task, which is a dual-step lightweight denoising scheme. First, in order to avoid the influence of glitch noise on sparse signal reconstruction, Savitzky-Golay (S-G) filter is used to smooth the 2nd harmonic signal while retaining the change information effectively. Then, the well-tuned measurement matrix of compressed-sensing (CS) is applied to aggressively fetch the sparse principal components while bypassing most residual dynamic noises. Finally, the orthogonal matching pursuit (OMP) is used to reconstruct the 2nd harmonic signal according to sparsity constrain and the sparse principal components. Experimental results show that the performance of SGCS method is superior. Compared with other competitive methods the operation time of SGCS is the shortest. When the normalized SNR is 1, the average correct discrimination rate is 98.57%. Even if SNR reduces from 1 to 0.55, the WMS detection system still survives well, with the highest average correct discrimination rate of 89.34%.

Anti-Motion Interference Wearable Device for Monitoring Blood Oxygen Saturation Based on Sliding Window Algorithm

Wearable multi-physiological parameter monitoring technology can realize non-intrusive, non-invasive daily health monitoring of the human body. It has the characteristics of convenient operation, long-term continuous work, display of results, abnormal physiological condition alarm and wireless data transmission. First, an improved sliding window confidence propagation algorithm is proposed, which reduces the inefficient iterative process in the decoding process by correlation coefficients and reduces the running time of the algorithm by more than 1.5 times; designing a channel noise estimation method based on sliding window confidence propagation algorithm, and The source coding is similar. In order to estimate the local statistical parameters of the channel noise, the confidence propagation, the decoder uses the local partial probability of the adjacent accompanying child nodes to estimate the noise parameters of the channel noise. Secondly, the design and research of the blood oxygen saturation monitor, including filtering out high-frequency glitch noise, low-frequency baseline drift noise, and mixing and sudden motion interference noise, also achieved rapid and accurate extraction of pulse wave feature points, and calculated the blood oxygen value and pulse rate value. Compared with the traditional oximeter, the filtering algorithm and pulse wave feature point extraction algorithm on the oximeter software have less calculation amount and higher real-time performance. Finally, the relevant test experiment of the blood oxygen saturation monitor proves that the blood oximeter has good stability, accuracy and sensitivity. The practical use of anti-motion interference wearable devices not only shows that the wearable PPG sensor in this paper can stably obtain high-quality PPG signals, but also reflects its many applications in the field of real-time blood.

In-Orbit Performance Evaluation of a Spaceborne High Precision Fiber Optic Gyroscope

An in-orbit experiment was launched to evaluate the performance of the spaceborne high precision fiber optic gyroscopes (FOG). The three-axis in-orbit data of the FOG were analyzed using wavelet analysis method. Features of low frequency period terms and glitch noise were demonstrated. In addition, a method to extract the random noise from the in-orbit data is proposed based on the first-order difference method and the Pauta criterion. In addition, the random walk coefficient (RWC) of the FOG was calculated with the Allan variance method. Compared the ground test results, the in-orbit performance evaluation of Spaceborne High Precision Fiber Optic Gyroscope was verified.

Locally optimum network detectors of unmodeled gravitational wave bursts in glitch noise

The detection of unmodeled gravitational wave transients (bursts) using a network of interferometric detectors affected by non-Gaussian (glitchy) noise is studied, starting from first principles, for the simplest case where the source position on the celestial sphere is fiducially known from different (e.g., optical, radio, or neutrino) observations. Interferometer noise modelling is preliminarily discussed in an operational perspective. Two alternative, locally optimum detectors are proposed and evaluated in simulated realistic non-Gaussian (glitchy) noise, together with robust implementations which are tolerant against incomplete knowledge or fluctuations of the noise features. These detectors outperform those based on the unrealistic stationary/Gaussian noise assumption, and in principle, do not require preliminary ad hoc data vetoing or laundering. They are structurally akin to those adopted in current data analysis pipelines, preserving their correlation structure, and use simple memoryless nonlinearities for data preprocessing, with only a minor added computational burden.

Improving the Glitch Noise of .DELTA..SIGMA. D/A Converter Using the RTZ Waveform

This paper discusses the analytical result of the glitch noise improvement in the multi-bit delta sigma D/A converter with Data-Weighted-Averaging (DWA). The DWA-DAC is effective for the improvement measure of SNR deterioration with element deviation. However, the DWA-DAC has the problem that the accuracy decreases by the glitch noise. The glitch noise occurs by the timing skew. So we propose to use RTZ waveform (fixed code) that is appropriate for the DWA-DAC. In this result, we obtain that the accuracy is able to improve 10dB when the timing-skew is 100ps.

Detecting unmodeled GW bursts in non-Gaussian (glitchy) noise: two locally optimum network detectors

Two locally optimum interferometer-network statistics for detecting unmodeled gravitational wave bursts in a non-Gaussian impulsive (glitchy) noise background are introduced. These follow from two possible approaches, where the sought transient signals are alternatively assumed as (i) unknown but deterministic or (ii) random. The first approach yields a locally optimum generalized likelihood ratio test detector, based on the maximum likelihood estimate of the gravitational wave signal. The second makes only minimal (least informative) assumptions about the sought signals, and yields a special version of Kassam's generalized-cross-correlation test detector. Both outperform the standard coherent network detector based on the Gaussian noise assumption. In the realistic case where the glitch noise distribution is non-stationary in time, or incompletely characterized, robust versions of these locally optimum network detectors can be effectively used.

Design of a laminated current cell relocation 12-bit CMOS D/A converter with a high output impedance technique and a merged switching logic

A compact and low power 12-bit 300 MS/s current steering CMOS D/A converter is presented. The architecture of the D/A converter is based on the current steering 6 + 6 segmented type with a laminated current cell relocation technique. In order to improve the linearity and glitch noise, a high output impedance analog current cell is designed. Furthermore, for the purpose of reducing the chip area and power dissipation, a noble merged switching logic and a compact layout technique are proposed. To verify its performance, the chip was fabricated with 0.13 μm thick-gate 1-poly 6-metal N-well Samsung CMOS technology. The effective chip area is 0.26 mm2 (510 × 510 μm) with a power consumption of 100 mW. The measured INL and DNL are within ±3LSB and ±1LSB, respectively. The measured SFDR is about 70 dB, when the input frequency is 1 MHz at a clock frequency of 300 MHz.

A 12 b 200 kS/s 0.52 mA 0.47 mm2 Algorithmic A/D Converter for MEMS Applications

This work describes a 12b 200kS/s 0.52mA 0.47mm2 ADC for sensor applications such as motor control, 3-phase power control, and CMOS image sensors simultaneously requiring ultra-low power and small size. The proposed ADC is based on the conventional algorithmic architecture with a recycling signal path to optimize sampling rate, resolution, chip area, and power consumption. The input SHA with eight input channels employs a folded-cascode amplifier to achieve a required DC gain and a high phase margin. A 3-D fully symmetric layout with critical signal lines shielded reduces the capacitor and device mismatch of the multiplying D/A converter while switched-bias power-reduction circuits minimize the power consumption of analog amplifiers. Current and voltage references are integrated on chip with optional off-chip voltage references for low glitch noise. The down-sampling clock signal selects the sampling rate of 200kS/s and 10kS/s with a further reduced power depending on applications. The prototype ADC in a 0.18μm n-well 1P6M CMOS process demonstrates a maximum measured DNL and INL within 0.40 LSB and 1.97 LSB and shows a maximum SNDR and SFDR of 55dB and 70dB at all sampling frequencies up to 200kS/s, respectively. The ADC occupies an active die area of 0.47mm2 and consumes 0.94mW at 200kS/s and 0.63mW at 10kS/s with a 1.8V supply.

Si bipolar 2-GHz 6-bit flash A/D conversion LSI

A gigahertz-sampling-rate flash A/D (analog/digital)-conversion LSI using high-speed Si bipolar technology (SST-1B) is investigated. To improve comparator speed, a circuit technology to minimize the comparator-speed limiting factors with minimum power is investigated and applied. To enhance the dynamic accuracy, speed mismatch among comparators is also minimized using this circuit technology. To improve encoder speed, a quasi-Gray code is adopted and glitch noise is reduced with this code. The LSI performance at 1-GHz sampling rate is measured with a gigahertz-operation data acquisition system developed with the SST MSI family, and effective bits of 5.8 at an input frequency of 100 MHz and 4.8 at 500 MHz are achieved. This LSI also demonstrates the feasibility of a single-chip flash A/D converter with a gigahertz sampling rate using Si bipolar technology.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Syntactic analysis of seismic waveforms using augmented transition network grammars

The Augmented Transition Network (ATN) formalism provides a convenient environment for developing syntactic waveform analysis techniques. As an example, an ATN grammar that describes seismic glitch noise waveforms is presented. The grammar produces English descriptions of waveforms and reduces the false alarm rate of an automatic signal detection system. ATN grammars can be extended in several ways to provide error correcting and non-left-right parsing capabilities.