12 papers · ranked by Valyu relevance
Shanmukha Srinivas, Evan Masutani, Alexander Norbash, Albert Hsiao
Background phase errors in 4D Flow MRI may negatively impact blood flow quantification. In this study, we assessed their impact on cerebrovascular flow volume measurements, evaluated the benefit of manual image-based correction, and assessed the potential of a convolutional neural network (CNN), a form of deep…
Guangcai Sun, Jixiang Xiang, Mengdao Xing, Jun Yang + 1 more
Multichannel SAR is an effective approach to solving the contradiction between high azimuth resolution and wide swath. The goal of this paper is to obtain a new and effective method for estimating and compensating the interchannel phase error of the Chinese GF-3 Synthetic aperture radar (SAR). A channel phase error…
Fuqian Li, Wenjing Chen, Liang Zhang, Mohammed Bennamoun + 1 more
'Mingtao Feng'] Crossed-grating phase-shifting profilometry (CGPSP) has great utility in three-dimensional shape measurement due to its ability to acquire horizontal and vertical phase maps in a single measurement. However, CGPSP is extremely sensitive to the non-linearity effect of a digital fringe projection system…
Bo Li, Falin Liu, Chongbin Zhou, Yuanhao Lv + 2 more
'Ram M. Narayanan'] Defocus of the reconstructed image of synthetic aperture radar (SAR) occurs in the presence of the phase error. In this work, a phase error correction method is proposed for compressed sensing (CS) radar imaging based on approximated observation. The proposed method has better image focusing ability…
M. Ethan MacDonald, Nils D. Forkert, G. Bruce Pike, Richard Frayne + 1 more
Phase contrast (PC) magnetic resonance (MR) imaging is a powerful method for measuring blood flow velocity in human subjects and can provide key hemodynamic information about the vasculature. However, concern has been raised about measurement accuracy , in particular, the impact of phase error from the application of…
Zhuang Lv, Kaifeng Zhu, Xin He, Lei Zhang + 6 more
'Jun Wang' 'Xin Zhang' 'Ruidong Hao' 'Robert Sitnik'] Fringe projection profilometry (FPP) is prone to phase unwrapping error (PUE) due to phase noise and measurement conditions. Most of the existing PUE-correction methods detect and correct PUE on a pixel-by-pixel or partitioned block basis and do not make full use of…
Goran T. Djordjevic, Dejan N. Milic, Bata Vasic, Jarosław Makal + 2 more
'Bane Vasic' 'Syed A. Jafar'] We examine the effects of imperfect phase estimation of a reference signal on the bit error rate and mutual information over a communication channel influenced by fading and thermal noise. The Two-Wave Diffuse-Power (TWDP) model is utilized for statistical characterization of propagation…
Lorant A. Muth
This study was conducted to verify that the probe-position error correction can be successfully applied to real data obtained on a planar near-field range where probe position errors are known. Since probe position-error correction is most important at high frequencies, measurements were made at 60 GHz. Six planar…
Pengcheng Hu, Jinghao Zhu, Xuanbiao Guo, Jiubin Tan
This paper presents a real-time method to compensate for the variable cyclic error in a homodyne laser interferometer. The parameters describing the quadrature signals of the interferometer are estimated using simple peak value detectors. The cyclic error in the homodyne laser interferometer was then corrected through…
Rongjun Mu, Teng Long, Kamil Krasuski, Chris Rizos
For the tracking of high-dynamic satellite navigation signals, the conventional scalar tracking loop (STL) is vulnerable. Frequent signal-tracking interruption affects the continuity of navigation. The vector tracking loop (VTL) can overcome this disadvantage. However, there are some difficulties in implementing…
Haijin Fu, Yue Wang, Pengcheng Hu, Jiubin Tan + 1 more
Even after the Heydemann correction, residual nonlinear errors, ranging from hundreds of picometers to several nanometers, are still found in heterodyne laser interferometers. This is a crucial factor impeding the realization of picometer level metrology, but its source and mechanism have barely been investigated. To…
Jiawei Yu, Qiang Wang, Guozhong Zhou, Dong He + 4 more
'Xiang Liu' 'Wenyi Lv' 'Yongmei Huang'] Photoelectric angle encoders, working as position sensors, have a great influence on the accuracy and stability of telescope control systems (TCS). In order to improve the tracking precision of TCS, a method based on subdivision error compensation for photoelectric angle encoders…