Artykuły w czasopismach: „Jitter”

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Manzoor, Kamran, Umar Manzoor i Samia Nefti. "An Efficient System for Video Stabilization by Differentiating between Intentional and Un-Intentional Jitters". International Journal of Knowledge Society Research 1, nr 4 (październik 2010): 42–53. http://dx.doi.org/10.4018/jksr.2010100104.

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Video stabilization is one of the most important enhancements where jittering caused by un-intentional movements is removed. Existing video stabilizer software and tools cannot differentiate between intentional and un-intentional jitters in the video and treats both equally. In this paper, the authors propose an efficient and practical approach of video stabilization by differentiating between an intentional and un-intentional jitter. Their method takes jittered video as input, and differentiates between intentional and an un-intentional jitter without affecting its visual quality while producing stabilized video only if jitter is found to be un-intentional. While most previous methods produce stabilized videos with low resolution, this reduces quality. The proposed system has been evaluated on a large number of real life videos and results promise to support the implementation of the solution.

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Rao, Fangyi, i Sanjeev Gupta. "Accurate and Efficient BER Calculation by Statistical Simulation Based on Physical Transmit Jitter Model". International Symposium on Microelectronics 2010, nr 1 (1.01.2010): 000593–600. http://dx.doi.org/10.4071/isom-2010-wp2-paper6.

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Statistical analysis provides an efficient alternative to the traditional Monte Carlo simulation for extremely low BER calculation in high speed serial link designs. Transmitter (TX) jitter posts a huge challenge in statistical simulation due to its pattern- and time-dependent nature and the resulting computational complexity. This paper presents a fast yet rigorous approach to calculate TX jitter in statistical simulation based on physical models of various jitter components. The approach accurately captures effects of uncorrelated random jitters, jitter amplification by channel dispersion, frequency dependency of periodic jitter and data duty-cycle-distortion.

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Zou, Hai Dong, i Liang Qian. "Research on PTP Clock Synchronization in IP". Advanced Materials Research 1079-1080 (grudzień 2014): 762–65. http://dx.doi.org/10.4028/www.scientific.net/amr.1079-1080.762.

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A certain delay jitter will impact the time synchronization accuracy of PTP system in the IP packet switched network. Look the network delay jitters as independently distributed random noise, and use the Least Mean Square (LMS) filter to filter out the noise, that will help to relieve the delay jitter on the system synchronization accuracy. The simulation results show that, by using the LMS algorithm, the research can increase the synchronization accuracy and decrease the bad impact on master and slave time synchronization of packet delay jitter.

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Hancock, Kenneth E., Yoojin Chung i Bertrand Delgutte. "Neural ITD coding with bilateral cochlear implants: effect of binaurally coherent jitter". Journal of Neurophysiology 108, nr 3 (1.08.2012): 714–28. http://dx.doi.org/10.1152/jn.00269.2012.

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Poor sensitivity to the interaural time difference (ITD) constrains the ability of human bilateral cochlear implant users to listen in everyday noisy acoustic environments. ITD sensitivity to periodic pulse trains degrades sharply with increasing pulse rate but can be restored at high pulse rates by jittering the interpulse intervals in a binaurally coherent manner (Laback and Majdak. Binaural jitter improves interaural time-difference sensitivity of cochlear implantees at high pulse rates. Proc Natl Acad Sci USA 105: 814–817, 2008). We investigated the neural basis of the jitter effect by recording from single inferior colliculus (IC) neurons in bilaterally implanted, anesthetized cats. Neural responses to trains of biphasic pulses were measured as a function of pulse rate, jitter, and ITD. An effect of jitter on neural responses was most prominent for pulse rates above 300 pulses/s. High-rate periodic trains evoked only an onset response in most IC neurons, but introducing jitter increased ongoing firing rates in about half of these neurons. Neurons that had sustained responses to jittered high-rate pulse trains showed ITD tuning comparable with that produced by low-rate periodic pulse trains. Thus, jitter appears to improve neural ITD sensitivity by restoring sustained firing in many IC neurons. The effect of jitter on IC responses is qualitatively consistent with human psychophysics. Action potentials tended to occur reproducibly at sparse, preferred times across repeated presentations of high-rate jittered pulse trains. Spike triggered averaging of responses to jittered pulse trains revealed that firing was triggered by very short interpulse intervals. This suggests it may be possible to restore ITD sensitivity to periodic carriers by simply inserting short interpulse intervals at select times.

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Finneran, James, Jason Mulsow i Dorian Houser. "Studying dolphin biosonar with the jittered-echo paradigm". Journal of the Acoustical Society of America 153, nr 3_supplement (1.03.2023): A95. http://dx.doi.org/10.1121/10.0018283.

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In his 1979 paper “Perception of echo phase information in bat sonar” [Science 204, 1336–1338], Jim Simmons introduced the “jittered-echo” paradigm. In this method, bats discriminated between electronic echoes with fixed delay (i.e., simulating fixed range) and those with delays that alternated (“jittered”) on successive echoes. The jittered-echo paradigm was developed to minimize the interfering effects of head movement, under the assumption that head movement between successive pulse emissions is negligible. Echo delay thresholds obtained with the jitter technique are small, with multiple studies reporting sub-microsecond echo delay thresholds in the big brown bat. The jitter method has also been controversial, because of the extremely low echo delay resolution (10 ns) and sensitivity to echo phase (fine structure) reported by Simmons. Recently, the jitter delay paradigm has been adapted for underwater use with dolphins. Results with dolphins show qualitative similarities to those from bats: echo delay thresholds below 1 μs and sensitivity to echo fine structure. This talk will briefly review Simmons’ and other’s biosonar jitter experiments with bats, then present in detail experiments with bottlenose dolphins featuring jittered echo delay and phase.

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Kwon, Seong-Cheol, Mun-Shin Jo i Hyun-Ung Oh. "Experimental Validation of Fly-Wheel Passive Launch and On-Orbit Vibration Isolation System by Using a Superelastic SMA Mesh Washer Isolator". International Journal of Aerospace Engineering 2017 (2017): 1–16. http://dx.doi.org/10.1155/2017/5496053.

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On-board appendages with mechanical moving parts for satellites produce undesirable micro-jitters during their on-orbit operation. These micro-jitters may seriously affect the image quality from high-resolution observation satellites. A new application form of a passive vibration isolation system was proposed and investigated using a pseudoelastic SMA mesh washer. This system guarantees vibration isolation performance in a launch environment while effectively isolating the micro-disturbances from the on-orbit operation of jitter source. The main feature of the isolator proposed in this study is the use of a ring-type mesh washer as the main axis to support the micro-jitter source. This feature contrasts with conventional applications of the mesh washers where vibration damping is effective only in the thickness direction of the mesh washer. In this study, the basic characteristics of the SMA mesh washer isolator in each axis were measured in static tests. The effectiveness of the design for the new application form of the SMA mesh washer proposed in this study was demonstrated through both launch environment vibration test at qualification level and micro-jitter measurement test which corresponds to on-orbit condition.

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Krom, Guus de. "A Cepstrum-Based Technique for Determining a Harmonics-to-Noise Ratio in Speech Signals". Journal of Speech, Language, and Hearing Research 36, nr 2 (kwiecień 1993): 254–66. http://dx.doi.org/10.1044/jshr.3602.254.

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A new method to calculate a spectral harmonics-to-noise ratio (HNR) in speech signals is presented. The method involves discrimination between harmonic and noise energy in the magnitude spectrum by means of a comb-liftering operation in the cepstrum domain. Sensitivity of HNR to (a) additive noise and (b) jitter was tested with synthetic vowel-like signals, generated at 10 fundamental frequencies. All jitter and noise signals were analyzed at three window lengths in order to investigate the effect of the length of the analysis frame on the estimated HNR values. Results of a multiple linear regression analysis with noise or jitter, F 0 , and window length as predictors for HNR indicate a major effect of both noise and jitter on HNR, in that HNR decreases almost linearly with increasing noise levels or increasing jitter. The influence of F 0 and window length on HNR is small for the jittered signals, but HNR increases considerably with increasing F 0 or window length for the noise signals. We conclude that the method seems to be a valid technique for determining the amount of spectral noise, because it is almost linearly sensitive to both noise and jitter for a large part of the noise or jitter continuum. The strong negative relation between HNR and jitter illustrates that spectral noise measures cannot simply be taken as indicators of the actual amount of noise in the time signal. Instead, HNR integrates several aspects of the acoustic stability of the signal. As such, HNR may be a useful parameter in the analysis of voice quality, although it cannot be directly interpreted in terms of underlying glottal events or perceptual characteristics.

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8

Chin, J., i A. Cantoni. "Phase jitter/spl equiv/timing jitter?" IEEE Communications Letters 2, nr 2 (luty 1998): 54–56. http://dx.doi.org/10.1109/4234.660802.

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Campbell, Jackie, i Massimo Leandri. "Measuring Latency Variations in Evoked Potential Components Using a Simple Autocorrelation Technique". Computational and Mathematical Methods in Medicine 2021 (22.09.2021): 1–8. http://dx.doi.org/10.1155/2021/8875445.

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Interpretation of averaged evoked potentials is difficult when the time relationship between stimulus and response is not constant. Later components are more prone to latency jitter, making them insufficiently reliable for routine clinical use even though they could contribute to greater understanding of the functioning of polysynaptic components of the afferent nervous system. This study is aimed at providing a simple but effective method of identifying and quantifying latency jitter in averaged evoked potentials. Autocorrelation techniques were applied within defined time windows on simulated jittered signals embedded within the noise component of recorded evoked potentials and on real examples of somatosensory evoked potentials. We demonstrated that the technique accurately identifies the distribution and maximum levels of jitter of the simulated components and clearly identifies the jitter properties of real evoked potential recording components. This method is designed to complement the conventional analytical methods used in neurophysiological practice to provide valuable additional information about the distribution of latency jitter within an averaged evoked potential. It will be useful for the assessment of the reliability of averaged components and will aid the interpretation of longer-latency, polysynaptic components such as those found in nociceptive evoked potentials.

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Ukachoke, C., P. Ashby, A. Basinsk i J. A. Sharpe. "Usefulness of Single Fiber EMG for Distinguishing Neuromuscular from Other Causes of Ocular Muscle Weakness". Canadian Journal of Neurological Sciences / Journal Canadien des Sciences Neurologiques 21, nr 2 (maj 1994): 125–28. http://dx.doi.org/10.1017/s0317167100049040.

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Abstract:Consecutive patients (n = 114), who had single fiber electromyography of the frontalis muscles for symptoms suggestive of ocular myasthenia gravis, were followed up for a mean of 14 months (3-64 mos). At follow up, based on strict criteria, 23 patients were classified as having ocular myasthenia gravis, 8 patients were diagnosed as having mitochondrial myopathy or oculopharyngeal dystrophy, 18 patients were found to have other diseases and 65 patients remained without a definite diagnosis. The single fiber electromyography data of these patients were then reviewed. The patients with ocular myasthenia gravis had, on average, more than 7/20 single fiber pairs with jitter > 45 μs and mean jitter of 56 μs. The 8 patients with mitochondrial myopathy or oculopharyngeal dystrophy had an average of 5/20 single fiber pairs with jitter > 45 μs and a mean jittter of 52 μs and could not be separated from the group with ocular myasthenia gravis on the basis of the single fiber electromyography results. The 18 patients with definite other diagnosis had an average of less than 1/20 single fiber pair with jitter > 45 μs and a mean jitter of 25 μs. This group could be clearly separated from the group with ocular yasthenia gravis. We conclude that single fiber electromyelography is useful in the separation of ocular myasthenia gravis from other causes of oculomotor weakness except mitochondrial myopathy and oculopharyngeal dystrophy.

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Khademi, Fatemeh, Chih-Yang Chen i Ziad M. Hafed. "Visual feature tuning of superior colliculus neural reafferent responses after fixational microsaccades". Journal of Neurophysiology 123, nr 6 (1.06.2020): 2136–53. http://dx.doi.org/10.1152/jn.00077.2020.

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Despite being diminutive, microsaccades still jitter retinal images. We investigated how such jitter affects superior colliculus (SC) activity. We found that SC neurons exhibit short-latency visual reafferent bursts after microsaccades. These bursts reflect not only the spatial luminance profiles of visual patterns but also how such profiles are shifted by eye movement size and direction. These results indicate that the SC continuously represents visual patterns, even as they are jittered by the smallest possible saccades.

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Benea, Licinius, Mikael Carmona, Viktor Fischer, Florian Pebay-Peyroula i Romain Wacquez. "Impact of the Flicker Noise on the Ring Oscillator-based TRNGs". IACR Transactions on Cryptographic Hardware and Embedded Systems 2024, nr 2 (12.03.2024): 870–89. http://dx.doi.org/10.46586/tches.v2024.i2.870-889.

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Ring Oscillators (RO) are often used in true random number generators (TRNG). Their jittered clock signal, used as randomness source, originates from thermal and flicker noises. While thermal noise jitter is generally used as the main source of randomness, flicker noise jitter is not due to its autocorrelation. This work aims at qualitatively settling the issue of the influence of flicker noise in TRNGs, as its impact increases in newer technology nodes. For this, we built a RO behavioural model, which generates time series equivalent to a jittered RO signal. It is then used to generate the output of an elementary RO-TRNG. Despite general expectations, the autocorrelation inside the output bit stream is reduced when the amplitude of flicker noise increases. The model shows that this effect is caused by the sampling of the jittered signal by the second oscillator, which hides the behaviour of the absolute jitter, causes resetting of the perceived phase, and suppresses any memory effect. The inclusion of flicker noise as a legitimate noise source can increase the TRNG output bit rate by a factor of four for the same output entropy rate. This observation opens new perspectives towards more efficient stochastic models of the RO-TRNGs.

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Balestrieri, Eulalia, Francesco Picariello, Sergio Rapuano i Ioan Tudosa. "The jitter measurement ways: The jitter graphs". IEEE Instrumentation & Measurement Magazine 22, nr 4 (sierpień 2019): 50–57. http://dx.doi.org/10.1109/mim.2019.8782200.

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Balestrieri, Eulalia, Luca De Vito, Francesco Lamonaca, Francesco Picariello, Sergio Rapuano i Ioan Tudosa. "The jitter measurement ways: The jitter decomposition". IEEE Instrumentation & Measurement Magazine 23, nr 7 (październik 2020): 3–12. http://dx.doi.org/10.1109/mim.2020.9234759.

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Ren, Nan, Zaiming Fu, Shengcun Lei, Hanglin Liu i Shulin Tian. "Methodology for Digital Synthesis of Deterministic and Random Jitter Generation on Rising or Falling Edges of Data Pattern". Electronics 8, nr 12 (9.12.2019): 1510. http://dx.doi.org/10.3390/electronics8121510.

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Jitter is becoming an important factor in high-speed serial link and integrated circuits (ICs). Generating controllable jitter plays a crucial role in simulating the test environment of high-data links, evaluating the performance of IC, preventing jitter in high-speed serial link, and even testing the synchronous trigger circuit. In this paper, a digital synthesis for jitter generation and a logical combination method for selecting jitter on the rising edge or falling edge of a data pattern are presented. Precisely controllable jitter is generated by digital synthesis, including sinusoidal period jitter, rectangular period jitter, duty cycle distortion (DCD) jitter, and adjustable random jitter. Additionally, the validity and accuracy of the proposed method were demonstrated by hardware experiments, where the jitter frequency had an accuracy of ±30 ppm and the jitter amplitude had a step of 2 ps.

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Liu, Jialun, Wenhui Li i Yifan Sun. "Memory-Based Jitter: Improving Visual Recognition on Long-Tailed Data with Diversity in Memory". Proceedings of the AAAI Conference on Artificial Intelligence 36, nr 2 (28.06.2022): 1720–28. http://dx.doi.org/10.1609/aaai.v36i2.20064.

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This paper considers deep visual recognition on long-tailed data. To make our method general, we tackle two applied scenarios, i.e. , deep classification and deep metric learning. Under the long-tailed data distribution, the most classes (i.e., tail classes) only occupy relatively few samples and are prone to lack of within-class diversity. A radical solution is to augment the tail classes with higher diversity. To this end, we introduce a simple and reliable method named Memory-based Jitter (MBJ). We observe that during training, the deep model constantly changes its parameters after every iteration, yielding the phenomenon of weight jitters. Consequentially, given a same image as the input, two historical editions of the model generate two different features in the deeply-embedded space, resulting in feature jitters. Using a memory bank, we collect these (model or feature) jitters across multiple training iterations and get the so-called Memory-based Jitter. The accumulated jitters enhance the within-class diversity for the tail classes and consequentially improves long-tailed visual recognition. With slight modifications, MBJ is applicable for two fundamental visual recognition tasks, i.e., deep image classification and deep metric learning (on long-tailed data). Extensive experiments on five long-tailed classification benchmarks and two deep metric learning benchmarks demonstrate significant improvement. Moreover, the achieved performance are on par with the state of the art on both tasks.

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Gentleman, Alastair. "Lacquer jitter". New Scientist 198, nr 2651 (kwiecień 2008): 19. http://dx.doi.org/10.1016/s0262-4079(08)60900-8.

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Klassen, R. Victor. "Filtered Jitter". Computer Graphics Forum 19, nr 4 (grudzień 2000): 223–30. http://dx.doi.org/10.1111/1467-8659.00459.

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RYAN, MATTHEW, REBECCA MARTIN, MARTHA B. DENCKLA, STEWART H. MOSTOFSKY i E. MARK MAHONE. "Interstimulus jitter facilitates response control in children with ADHD". Journal of the International Neuropsychological Society 16, nr 2 (11.12.2009): 388–93. http://dx.doi.org/10.1017/s1355617709991305.

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AbstractInterstimulus “jitter” involves randomization of intervals between successive stimulus events, and can facilitate performance on go/no-go tests among healthy adults, though its effect in clinical populations is unclear. Children with Attention-deficit/Hyperactivity Disorder (ADHD) commonly exhibit deficient response control, leading to increased intra-subject variability (ISV), which has been linked to anomalous functioning within frontal circuits, as well as their interaction with posterior “default mode” regions. We examined effects of interstimulus jitter on response variability in 39 children, ages 9–14 years (25 ADHD, 14 controls). Participants completed 2 computerized go/no-go tests: one with fixed interstimulus interval (ISI) and one with jittered ISI. Repeated measures analysis of variance (ANOVA) revealed a significant group–by test interaction, such that introduction of jitter produced a significant decrease in ISV among children with ADHD, but not among controls. Whereas children with ADHD were significantly more variable than controls on the go/no-go test with fixed ISI, their performance with jittered ISI was equivalent to that of controls. Jittering stimulus presentation provides a nonpharmacologic mechanism for improving response control in ADHD. This bottom-up approach may be mediated by increases in vigilance through noradrenergic circuits that facilitate maintenance of frontal circuits critical to response control. (JINS, 2010, 16, 388–393.)

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Aryandaru, Rico, Awang Noor Indra Wardana i Agus Arif. "Komparasi Protokol Komunikasi pada Sistem Produksi Siber-Fisik berbasis IEC 61499". Jurnal EECCIS (Electrics, Electronics, Communications, Controls, Informatics, Systems) 14, nr 1 (24.04.2020): 35–40. http://dx.doi.org/10.21776/jeeccis.v14i1.630.

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The change in the concept of an automation pyramid into an automation cloud in a cyber-physical production system makes data communication no longer stratified but can be done directly between devices. Based on IEC 61499, which defines the function blocks for building such communications, communication protocols can be run on various devices. Several communication protocols that can fulfill these requirements are OPC-UA, FBDK / IP, and MQTT. The research was conducted by comparing the three communication protocols for latency parameters and their jitters. The test method used to compare latency parameters is the variance analysis test and the Tukey test. The jitter value of the protocols are compared to the standard deviation parameter. The test results showed that the MQTT communication protocol had a faster latency value, with a 95% confidence level. The standard deviation of the variation value for OPC-UA, FBDK / IP, and MQTT showed the jitter value of 0.72 seconds, 0.35 seconds, and 0.64 seconds. Comparing the three communication protocols' standard deviation values showed that the FBDK / IP communication protocol has significantly less jitter than the OPC-UA and MQTT communication protocols.

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Sun, Li Cheng, i Zheng Wu. "Influence of Synchronous Jitter on GPS Receiving". Advanced Materials Research 760-762 (wrzesień 2013): 511–15. http://dx.doi.org/10.4028/www.scientific.net/amr.760-762.511.

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Synchronous jitter is one of the factors that influence GPS receiving precision a lot. Jitter is the effective data offset off the ideal position in a data stream, which is divided into deterministic jitter and random jitter. A theoretical analysis was done to the influence of jitter. It can be seen that bit error rate gets larger due to the jitter of synchronous clock. By means of a simulation platform, a simulation was done to the synchronous jitter influence on bit error rate in the circumstance of white noise and single frequency interference. The result shows that as the synchronous jitter gets larger, the system bit error rate gets larger and the system function gets worse.

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Niitsu, Kiichi, Kazunori Sakuma, Naohiro Harigai, Daiki Hirabayashi, Nobukazu Takai, Takahiro J. Yamaguchi i Haruo Kobayashi. "Design Methodology and Jitter Analysis of a Delay Line for High-Accuracy On-Chip Jitter Measurements". Key Engineering Materials 596 (grudzień 2013): 176–80. http://dx.doi.org/10.4028/www.scientific.net/kem.596.176.

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This work presents the design methodology and jitter analysis of a delay line for high-accuracy on-chip jitter measurements. Jitter generated in the delay lines degrades the accuracy of on-chip jitter measurements, and required to be minimized. In order to analyze and the jitter generation in the delay lines, SPICE simulation was performed with 65 nm CMOS technology. Simulation results show that jitter due to thermal noise can be reduced by enlarging the transistor sizes of both PMOS and NMOS. Based on the results, design methodology of a delay line is introduced for minimizing the jitter generation.

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Miyauchi, Kazuhiro, Isamu Wakabayashi i Hiroki Shibayama. "Analysis of timing jitter in digital transmission systems". Electronics and Communications in Japan (Part I: Communications) 84, nr 8 (10.04.2001): 1–13. http://dx.doi.org/10.1002/ecja.1027.

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AbstractAn analysis of timing jitter generation in band‐limited digital systems is presented. An integral representation of jitter spectral density in frequency domain is derived for typical transmission systems: baseband polar system, BPSK and QPSK with AWGN. Using the representation, one can calculate the jitter spectral density and jitter variance for any frequency characteristics of the channel by performing integration over a finite frequency domain. The jitter spectral density consists of three terms with different noise dependency, each of which is represented by a combination of three factors: a coefficient, tank function, and jitter source spectral density. As a typical application of the present theory, the jitter spectral density and rms jitter are calculated for a cosine rolloff scheme. The jitter dependency on the rolloff factor, Eb/N0, and timing tank parameters are calculated and discussed. © 2001 Scripta Technica, Electron Comm Jpn Pt 1, 84(8): 1–13, 2001

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Zhu, Ying, Tingting Yang, Mi Wang, Hanyu Hong, Yaozong Zhang, Lei Wang i Qilong Rao. "Jitter Detection Method Based on Sequence CMOS Images Captured by Rolling Shutter Mode for High-Resolution Remote Sensing Satellite". Remote Sensing 14, nr 2 (12.01.2022): 342. http://dx.doi.org/10.3390/rs14020342.

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Satellite platform jitter is a non-negligible factor that affects the image quality of optical cameras. Considering the limitations of traditional platform jitter detection methods that are based on attitude sensors and remote sensing images, this paper proposed a jitter detection method using sequence CMOS images captured by rolling shutter for high-resolution remote sensing satellite. Through the three main steps of dense matching, relative jitter error analysis, and absolute jitter error modeling using sequence CMOS images, the periodic jitter error on the imaging focal plane of the spaceborne camera was able to be measured accurately. The experiments using three datasets with different jitter frequencies simulated from real remote sensing data were conducted. The experimental results showed that the jitter detection method using sequence CMOS images proposed in this paper can accurately recover the frequency, amplitude, and initial phase information of satellite jitter at 100 Hz, 10 Hz, and 2 Hz. Additionally, the detection accuracy reached 0.02 pixels, which can provide a reliable data basis for remote sensing image jitter error compensation.

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Shi, Cheng, Zhi-Kang Ni, Jun Pan, Zhijie Zheng, Shengbo Ye i Guangyou Fang. "A Method for Reducing Timing Jitter’s Impact in Through-Wall Human Detection by Ultra-Wideband Impulse Radar". Remote Sensing 13, nr 18 (8.09.2021): 3577. http://dx.doi.org/10.3390/rs13183577.

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Ultra-wideband (UWB) impulse radar is widely used for through-wall human respiration detection due to its high range resolution and high penetration capability. UWB impulse radar emits very narrow time pulses, which can directly obtain the impulse response of the target. However, the time interval between successive pulses emitted is not ideally fixed because of timing jitter. This results in the impulse response position of the same target not being fixed, but it is related to slow-time. The clutter scattered by the stationary target becomes non-stationary clutter, which affects the accurate extraction of the human respiration signal. In this paper, we propose a method for reducing timing jitter’s impact in through-wall human detection by UWB impulse radar. After the received signal is processed by the Fast Fourier transform (FFT) in slow-time, we model the range-frequency matrix in the frequency domain as a superposition of the low-rank representation of jitter-induced clutter data and the sparse representation of human respiratory data. By only extracting the sparse component, the impact of timing jitter in human respiration detection can be reduced. Both numerical simulated data and experimental data demonstrate that our proposed method can effectively remove non-stationary clutter induced by timing jitter and improve the accuracy of the human target signal extraction.

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Niitsu, Kiichi, Masato Sakurai, Naohiro Harigai, Daiki Hirabayashi, Daiki Oki, Takahiro J. Yamaguchi i Haruo Kobayashi. "An Analytical Study on Jitter Accumulation in Interleaved Phase Frequency Detectors for High-Accuracy On-Chip Jitter Measurements". Key Engineering Materials 534 (styczeń 2013): 197–205. http://dx.doi.org/10.4028/www.scientific.net/kem.534.197.

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This work presents the analytical study on jitter accumulation in interleaved phase frequency detectors for high-accuracy on-chip jitter measurements. Jitter accumulation in phase frequency detector degrades the accuracy of on-chip jitter measurements, and required to be mitigated. In order to analyze and estimate the jitter accumulation in phase frequency detectors, SPICE simulation was performed with 65 nm CMOS technology. Simulation results show that, with a 50 mV power supply noise injection, jitter accumulation can be reduced from 1.03 ps to 0.49 ps (52% reduction) by using an interleaved architecture.

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Watanabe, Yuki, Satoshi Saikatsu, Michitaka Yoshino i Akira Yasuda. "Delta–sigma DAC with jitter-shaper-reducing jitter noise". Analog Integrated Circuits and Signal Processing 85, nr 2 (11.07.2015): 243–51. http://dx.doi.org/10.1007/s10470-015-0600-5.

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Finneran, James J., Madelyn G. Strahan, Jason Mulsow i Dorian S. Houser. "Effects of echo phase on bottlenose dolphin jittered-echo detection". Journal of the Acoustical Society of America 153, nr 6 (1.06.2023): 3324. http://dx.doi.org/10.1121/10.0019717.

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The ability of bottlenose dolphins to detect changes in echo phase was investigated using a jittered-echo paradigm. The dolphins' task was to produce a conditioned vocalization when phantom echoes with fixed echo delay and phase changed to those with delay and/or phase alternated (“jittered”) on successive presentations. Conditions included: jittered delay plus constant phase shifts, ±45° and 0°–180° jittered phase shifts, alternating delay and phase shifts, and random echo-to-echo phase shifts. Results showed clear sensitivity to echo fine structure, revealed as discrimination performance reductions when jittering echo fine structures were similar, but envelopes were different, high performance with identical envelopes but different fine structure, and combinations of echo delay and phase jitter where their effects cancelled. Disruption of consistent echo fine structure via random phase shifts dramatically increased jitter detection thresholds. Sensitivity to echo fine structure in the present study was similar to the cross correlation function between jittering echoes and is consistent with the performance of a hypothetical coherent receiver; however, a coherent receiver is not necessary to obtain the present results, only that the auditory system is sensitive to echo fine structure.

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Wang, Yanping, Xiaogang Sun, Jianting Zhao, Kunli Zhou, Yunfeng Lu, Jifeng Qu, Pengcheng Hu i Qing He. "Simulation Analysis of Phase Jitter in Differential Sampling of AC Waveforms Based on the Programmable Josephson Voltage Standard". Electronics 13, nr 10 (11.05.2024): 1890. http://dx.doi.org/10.3390/electronics13101890.

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The effect of phase jitter on differential sampling using the programmable Josephson voltage standard (PJVS) system is studied in this paper. A phase jitter model is established for the measured signal, and compensation coefficients for phase jitter removal are derived for three different post-processing methods based on the discrete Fourier transform algorithm (DFT). Based on our analysis, the phase jitter compensation coefficients are determined by the phase jitter angle distribution and harmonic order. Furthermore, after analyzing and simulating various common distributions, the phase jitter compensation coefficients have been verified. The simulation shows that when the standard deviation of the phase jitter angle is 20 ns, and the frequency of the measuring waveform is 3.46 kHz, the influence of the phase jitter is 1 × 10−7. The results of the simulation indicate that, in the differential sampling of AC waveforms using a PJVS system, phase jitter is one of the error terms for an uncertainty budget that cannot be neglected, particularly as the frequency of the measured waveforms increases.

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Anthonys, Gehan, Michael J. Cree i Lee Streeter. "Jitter Extraction in a Noisy Signal by Fast Fourier Transform and Time Lag Correlation". Applied Mechanics and Materials 884 (sierpień 2018): 113–21. http://dx.doi.org/10.4028/www.scientific.net/amm.884.113.

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Jitter in an electronic signal is any deviation in, or displacement of, the signal in time. This paper investigates on decomposition of two types of jitter, namely, periodic and random jitter in noisy signals. Generally, an oscilloscope generates an eye diagram by overlaying sweeps of different segments of a long data stream driven by the reference clock signal. We use the fast Fourier transform with time lag correlation of the signal since we do not have a clock reference signal and apply this technique to simulated noisy signals. We separately injected a random jitter (of known amount), periodic jitter (with known frequency and amount), and both together to various modulation frequencies of sinusoidal signals. The approach is validated by several experiments with numerous values in jitter parameters. When we separately inject random jitter (5 ps) and periodic jitter (5 ps at 4.37 MHz) to the signal, we obtained the results (4.52±0.25 ps) and (4.93±0.04 ps at 4.40±0.04 MHz), respectively.

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31

Ichiyama, K., M. Ishida, T. J. Yamaguchi i M. Soma. "Novel CMOS Circuits to Measure Data-Dependent Jitter, Random Jitter, and Sinusoidal Jitter in Real Time". IEEE Transactions on Microwave Theory and Techniques 56, nr 5 (maj 2008): 1278–85. http://dx.doi.org/10.1109/tmtt.2008.920174.

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Andrade-Lucio, José A., Oscar G. Ibarra-Manzano, Miguel A. Vazquez-Olguin i Yuriy S. Shmaliy. "Modifying the Kalman Filter for Random Jitter in Sampling Time". DESIGN, CONSTRUCTION, MAINTENANCE 4 (4.07.2024): 44–51. http://dx.doi.org/10.37394/232022.2024.4.5.

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It is known that time jitter can vary in nature and magnitude depending on how accurately the time scale is generated and the dynamic process is sampled. We modify the Kalman filter for white Gaussian random jitter and call it jitter Kalman filter (JKF). It is shown that to cope with time jitter the system noise covariance acquires an additional term proportional to the fractional time jitter standard deviation and the process rate. Based on numerical simulations, it is shown that if the process rate grows without limits then the estimation error caused by time jitter will also grow without limits. The conclusions are confirmed experimentally

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33

Ye, Z., Y. Xu, C. Wei, X. Tong i U. Stilla. "INFLUENCE OF IMAGE INTERPOLATION ON IMAGERY-BASED DETECTION AND COMPENSATION OF SATELLITE JITTER". ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences V-1-2020 (3.08.2020): 157–63. http://dx.doi.org/10.5194/isprs-annals-v-1-2020-157-2020.

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Abstract. Satellite jitter is a common and complicated phenomenon that degrades the geometric quality of high-resolution satellite images. Imagery-based detection and compensation of satellite jitter have recently been widely concerned. However, most of the existing studies overlook the issue of image interpolation in this topic involving subpixel measurements. In this study, the influence of image interpolation on imagery-based detection and compensation of satellite jitter is investigated. Four different interpolators are separately applied in dense least squares matching for jitter detection based on parallax observation and in intensity resampling for jitter distortion compensation. Experiments were carried out using ZiYuan-3 dataset to compare and analyze the results in the case of different image interpolation. The experimental results demonstrate the influence of image interpolation on imagery-based jitter processing. Inferior interpolators can induce pixel locking effect in subpixel matching and position-dependent systematic bias after image correction, which deteriorate the performance of jitter detection and compensation. To ensure the reliability, sophisticated interpolation algorithms with smaller phase errors are preferable in imagery-based jitter detection and compensation.

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34

Zhu, Y., M. Wang, Q. Zhu i J. Pan. "Detection and Compensation of Band-to-band Registration Error for Multi-spectral Imagery Caused By Satellite Jitter". ISPRS Annals of Photogrammetry, Remote Sensing and Spatial Information Sciences II-1 (7.11.2014): 69–76. http://dx.doi.org/10.5194/isprsannals-ii-1-69-2014.

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Satellite jitter has become a more and more important factor which affects the quality of imagery products with development of the high resolution satellite. This paper focused on analyzing the impact on multi-spectral image caused by satellite jitter and proposed a jitter detection and compensation method to improve the band-to-band registration efficiently when jitter exists without observation by attitude sensor. Firstly, the design of multi-spectral camera and the mainstream band-to-band registration method is introduced to explain factors influencing the registration accuracy. As one of factors, satellite jitter is an unexpected satellite movement and do have impact on registration on both across and along track but easy to be ignored for the lack of high frequency and accuracy attitude data. So next the jitter detection and compensation method is proposed, in which there are six main steps to achieve the analysis of registration accuracy with and without jitter and improvement of registration accuracy after compensation when the jitter cannot be ignored. Finally, three sets of multi-spectral images of ZY-3 were used to verify the proposed method. As a result, the error caused by satellite jitter was suppressed efficiently from 0.2pixels to 0.02pixels and registration accuracy (RMSE) was improved from 0.32 pixels to 0.11 pixels by the proposed method. The results indicate that the proposed method can detect and compensate the distortion of multi-spectral image caused by satellite jitter accurately and efficiently.

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35

Wang, Jiaqi, i Ping Qiu. "Photodetection-induced relative timing jitter in synchronized time-lens source for coherent Raman scattering microscopy". Journal of Innovative Optical Health Sciences 10, nr 05 (wrzesień 2017): 1743003. http://dx.doi.org/10.1142/s1793545817430039.

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Synchronized time-lens source is a novel method to generate synchronized optical pulses to mode-locked lasers, and has found widespread applications in coherent Raman scattering microscopy. Relative timing jitter between the mode-locked laser and the synchronized time-lens source is a key parameter for evaluating the synchronization performance of such synchronized laser systems. However, the origins of the relative timing jitter in such systems are not fully determined, which in turn prevents the experimental efforts to optimize the synchronization performance. Here, we demonstrate, through theoretical modeling and numerical simulation, that the photodetection could be one physical origin of the relative timing jitter. Comparison with relative timing jitter due to the intrinsic timing jitter of the mode-locked laser is also demonstrated, revealing different qualitative and quantitative behaviors. Based on the nature of this photodetection-induced timing jitter, we further propose several strategies to reduce the relative timing jitter. Our theoretical results will provide guidelines for optimizing synchronization performance in experiments.

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36

Platkiewicz, Jonathan, Eran Stark i Asohan Amarasingham. "Spike-Centered Jitter Can Mistake Temporal Structure". Neural Computation 29, nr 3 (marzec 2017): 783–803. http://dx.doi.org/10.1162/neco_a_00927.

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Jitter-type spike resampling methods are routinely applied in neurophysiology for detecting temporal structure in spike trains (point processes). Several variations have been proposed. The concern has been raised, based on numerical experiments involving Poisson spike processes, that such procedures can be conservative. We study the issue and find it can be resolved by reemphasizing the distinction between spike-centered (basic) jitter and interval jitter. Focusing on spiking processes with no temporal structure, interval jitter generates an exact hypothesis test, guaranteeing valid conclusions. In contrast, such a guarantee is not available for spike-centered jitter. We construct explicit examples in which spike-centered jitter hallucinates temporal structure, in the sense of exaggerated false-positive rates. Finally, we illustrate numerically that Poisson approximations to jitter computations, while computationally efficient, can also result in inaccurate hypothesis tests. We highlight the value of classical statistical frameworks for guiding the design and interpretation of spike resampling methods.

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37

Zhang, Shuoyan, Qinghe Sun, Xiaolong Chen, Bocheng Wang i Yifan Li. "ADC Clock Jitter Measurement Based on Simple Coherent Sampling Algorithm". Journal of Physics: Conference Series 2366, nr 1 (1.11.2022): 012045. http://dx.doi.org/10.1088/1742-6596/2366/1/012045.

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Abstract In a high-speed sampling system, the clock jitter of analog-to-digital converters (ADCs) will greatly affect its sampling accuracy, leading to the reduction of the signal-to-noise ratio (SNR) of the system output. Therefore, it is necessary to compensate the sampling results to reduce the sampling error caused by clock jitter by measuring the distribution sequence of jitter. In this paper, the influence of clock jitter on the ADC sampling process is analyzed, and an ADC clock jitter measurement scheme based on a simple coherent sampling algorithm is investigated. This scheme can accurately measure the distribution sequence of clock jitter, and has the characteristics of low computational complexity and high precision. The simulation results show that this algorithm can accurately measure the clock jitter sequence with root-mean-square (RMS) greater than 5ps when the amplitude noise of the input signal is greater than 35dB, and the relative error is less than 5%.

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38

Ye, G., J. Pan, M. Wang, Y. Zhu i S. Jin. "ANALYSIS: IMPACT OF IMAGE MATCHING METHODS ON JITTER COMPENSATION". ISPRS Annals of the Photogrammetry, Remote Sensing and Spatial Information Sciences V-3-2022 (17.05.2022): 611–18. http://dx.doi.org/10.5194/isprs-annals-v-3-2022-611-2022.

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Abstract. The degradation of image quality caused by satellite jitter has drawn attention, and many researches have illustrated the importance of the jitter compensation. As the essential component of jitter compensation, image matching involves in the determination of jitter processing accuracy. Hence, the impact of imaging matching methods on jitter compensation is explored in this paper. At first, a framework based on imaging matching is built for jitter compensation. Two typical sub-pixel accuracy matching methods (i.e. correlation coefficient and least squares matching, as well as phase correlation matching) could then be served for the framework. The experiments are designed by using multispectral images of GF-1 satellite, and quantitative evaluations show that compared with correlation coefficient and least squares matching, phase matching method makes the accuracy of obtained jitter curve increase with the amplitude error decreasing by more than 0.012 pixel as well as phase error decreasing by more than 0.0119 rad, and makes the quality of restored images improved on both geometry and radiation. It indicates that phase matching method has better performance with respect to the framework of jitter compensation in this paper.

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Palmisano, Stephen, Darren Burke i Robert S. Allison. "Coherent Perspective Jitter Induces Visual Illusions of Self-Motion". Perception 32, nr 1 (styczeń 2003): 97–110. http://dx.doi.org/10.1068/p3468.

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Palmisano et al (2000 Perception29 57–67) found that adding coherent perspective jitter to constant-velocity radial flow improved visually induced illusions of self-motion (vection). This was a surprising finding, because unlike pure radial flow, this jittering radial flow should have generated sustained visual–vestibular conflicts—previously thought to always reduce/impair vection. We attempted to ascertain the essential stimulus features for this jitter advantage for vection by examining three novel types of jitter display. While adding incoherent jitter to radial flow was found to impair vection, adding coherent non-perspective jitter had little effect on this subjective experience (contrary to the notion that jitter improves vection by reducing adaptation to radial flow). Importantly, we found that coherent perspective jitter not only improves the vection induced by radial flow, but it also appears to induce modest vection by itself (demonstrating that vection can still occur when there is an extreme mismatch between actual and expected vestibular activity). These results suggest that the previously demonstrated advantage for coherent perspective jitter was due (in part at least) to jittering vection combining with forwards vection in depth to produce a more compelling overall vection experience.

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40

Xu-Friedman, Matthew A., i Wade G. Regehr. "Dynamic-Clamp Analysis of the Effects of Convergence on Spike Timing. II. Few Synaptic Inputs". Journal of Neurophysiology 94, nr 4 (październik 2005): 2526–34. http://dx.doi.org/10.1152/jn.01308.2004.

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Sensory pathways in the nervous system possess mechanisms for decreasing spike-timing variability (“jitter”), probably to increase acuity. Most studies of jitter reduction have focused on convergence of many subthreshold inputs. However, many neurons receive only a few active inputs at any given time, and jitter reduction under these conditions is not well understood. We examined this issue using dynamic-clamp recordings in slices from mouse auditory brain stem. Significant jitter reduction was possible with as few as two inputs, provided the inputs had several features. First, jitter reduction was greatest and most reliable for supra-threshold inputs. Second, significant jitter reduction occurred when the distribution of input times had a rapid onset, i.e., for alpha- but not for Gaussian-distributed inputs. Third, jitter reduction was compromised unless late inputs were suppressed by the refractory period of the cell. These results contrast with the finding in the previous paper in which many subthreshold inputs contribute to jitter reduction, whether alpha- or Gaussian-distributed. In addition, convergence of many subthreshold inputs could fail to elicit any postsynaptic response when the input distribution outlasted the refractory period of the cell. These significant differences indicate that each means of reducing jitter has advantages and disadvantages and may be more effective for different neurons depending on the properties of their inputs.

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41

Jerger, James. "Jitter Produces Rollover". Journal of the American Academy of Audiology 13, nr 01 (styczeń 2002): i. http://dx.doi.org/10.1055/s-0040-1715942.

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42

Jovanović, Goran, Mile Stojč, N. A. ev i Tatjana Nikolić. "Programmable jitter generator". International Journal of Reasoning-based Intelligent Systems 4, nr 1/2 (2012): 39. http://dx.doi.org/10.1504/ijris.2012.046490.

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43

Horiuchi, Noriaki. "Ultralow timing jitter". Nature Photonics 6, nr 2 (luty 2012): 71. http://dx.doi.org/10.1038/nphoton.2012.17.

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44

Walker, J., i A. Cantoni. "Modeling of the synchronization process jitter spectrum with input jitter". IEEE Transactions on Communications 47, nr 2 (1999): 316–24. http://dx.doi.org/10.1109/26.752138.

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45

She, Lei, Yanshen Fang, Liang Hu, Rui Su i Xin Fu. "Mitigating jitter in droplet stream by uniform charging". Physics of Fluids 34, nr 11 (listopad 2022): 111704. http://dx.doi.org/10.1063/5.0129057.

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Monodisperse droplets induced by Plateau–Rayleigh instability of liquid jet are widely applied. Due to spatial jitter, the spacing between droplets becomes uneven as the working distance increases. We found that the jitter can be ameliorated by uniformly charging the droplets. Under the electrostatic forces, the droplets align at uniform spacing over a long distance. Nevertheless, radial jitter emerges when the charging voltage is too high. The effect of charging on the jitter was modeled and validated by experiments. A recommended charging parameters configuration is given considering a trade-off between axial and radial jitter to obtain evenly distributed droplets.

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46

Ragab, Ahmed, Yang Liu, Kangmin Hu, Patrick Chiang i Samuel Palermo. "Receiver Jitter Tracking Characteristics in High-Speed Source Synchronous Links". Journal of Electrical and Computer Engineering 2011 (2011): 1–15. http://dx.doi.org/10.1155/2011/982314.

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High-speed links which employ source synchronous clocking architectures have the ability to track correlated jitter between clock and data channels up to high frequencies. However, system timing margins are degraded by channel skew between clock and data signals and high-frequency loss. This paper describes how these key channel effects impact the jitter performance and influence the clocking architecture of high-speed source synchronous links. Tradeoffs in complexity and jitter tracking performance of common per-channel de-skew circuits are discussed, along with how band-pass filtering can be leveraged to provide additional jitter filtering at the receiver. Jitter tolerance analysis for a 10 Gb/s system shows that a near all-pass delay-locked loop (DLL) and phase-interpolator- (PI-) based de-skew performs best under low skew conditions, while, at high skew, architectures which leverage band-pass clock filtering or a phase-locked loop (PLL) for increased jitter filtering are more suitable. De-skew based on injection-locked oscillators (ILOs) offer a reduced complexity design and competitive jitter tolerance over a wide skew range.

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Bian, Boyuan, Feng Zhou i Xiaoman Li. "Jitter-Caused Clutter and Drift-Caused Clutter of Staring Infrared Sensor in Geostationary Orbit". Sensors 23, nr 11 (2.06.2023): 5278. http://dx.doi.org/10.3390/s23115278.

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For staring infrared sensors in geostationary orbit, the clutter caused by the high-frequency jitter and low-frequency drift of the sensor line-of-sight (LOS) is the impact of background features, sensor parameters, LOS motion characteristics, and background suppression algorithms. In this paper, the spectra of LOS jitter caused by cryocoolers and momentum wheels are analyzed, and the time-related factors such as the jitter spectrum, the detector integration time, the frame period, and the temporal differencing background suppression algorithm are considered comprehensively; they are combined into a background-independent jitter-equivalent angle model. A jitter-caused clutter model in the form of multiplying the background radiation intensity gradient statistics by the jitter-equivalent angle is established. This model has good versatility and high efficiency and is suitable for the quantitative evaluation of clutter and the iterative optimization of sensor design. Based on satellite ground vibration experiments and on-orbit measured image sequences, the jitter-caused clutter and drift-caused clutter models are verified. The relative deviation between the model calculation and the actual measurement results is less than 20%.

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Sun, Hua Fang, Xin Ning Liu i Xin Chen. "Optimum Digital Filter for High-Performance All-Digital Phase-Locked Loop". Applied Mechanics and Materials 182-183 (czerwiec 2012): 587–92. http://dx.doi.org/10.4028/www.scientific.net/amm.182-183.587.

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The effect of all-digital phase-locked loop (ADPLL) digital filter parameters on the jitter is investigated in time domain, and a systematic design procedure for ADPLL is presented. The pro-posed method not only estimates the output jitter of an ADPLL, but also finds the optimal filter pa-rameter minimizing the overall ADPLL timing jitter. To verify the theoretic analysis, an ADPLL behavior model in matlab is designed. The simulation shows significant performance improvement on the timing jitter.

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Dehbovid, Hadi, Habib Adarang i Mohammad Bagher Tavakoli. "Nonlinear analysis of VCO jitter generation using Volterra series". COMPEL - The international journal for computation and mathematics in electrical and electronic engineering 37, nr 2 (5.03.2018): 755–71. http://dx.doi.org/10.1108/compel-04-2017-0166.

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PurposeCharge pump phase locked loops (CPPLLs) are nonlinear systems as a result of the nonlinear behavior of voltage-controlled oscillators (VCO). This paper aims to specify jitter generation of voltage controlled oscillator phase noise in CPPLLs, by considering approximated practical model for VCO. Design/methodology/approachCPPLL, in practice, shows nonlinear behavior, and usually in LC-VCOs, it follows second-degree polynomial function behavior. Therefore, the nonlinear differential equation of the system is obtained which shows the CPPLLs are a nonlinear system with memory, and that Volterra series expansion is useful for such systems. FindingsIn this paper, by considering approximated practical model for VCO, jitter generation of voltage controlled oscillator phase noise in CPPLLs is specified. Behavioral simulation is used to validate the analytical results. The results show a suitable agreement between analytical equations and simulation results. Originality/valueThe proposed method in this paper has two advantages over the conventional design and analysis methods. First, in contrast to an ideal CPPLL, in which the characteristic of the VCO’s output frequency based on the control voltage is linear, in the present paper, a nonlinear behavior was considered for this characteristic in accordance with the real situations. Besides, regarding the simulations in this paper, a behavior similar to the second-degree polynomial was considered, which caused the dependence of the produced jitter’s characteristic corner frequency on the jitter’s amplitude. Second, some new nonlinear differential equations were proposed for the system, which ensured the calculation of the produced jitter of the VCO phase noise in CPPLLs. The presented method is general enough to be used for designing the CPPLL.

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Wang, Zhi Jie, Yan Yan Hao i Hui Lian. "Effect of Random Jitter on Performance of LDPC". Applied Mechanics and Materials 380-384 (sierpień 2013): 3513–16. http://dx.doi.org/10.4028/www.scientific.net/amm.380-384.3513.

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Low density parity check codes (LDPC) by now is an excellent channel code that approaches Shannons limit. In order to get the effect of random jitter on performance of LDPC, a simulation model is constructed in this paper. Interpolation, filter delay and decimation methods are used to simulate random jitter induced by circuits of the receiver, changing filter delay to control the jitter step length. Thus the bit error rate of LDPC decoder is gotten that shows the sensitivity of LDPC to synchronization jitter. This paper concludes that, complying with channel coding block in DVB-S2, the bit error rate of LDPC decoder goes up on an exponential trend with the effect of random jitter simulation.

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