English
Related papers

Related papers: 2-D Coherence Factor for Sidelobe and Ghost Suppre…

200 papers

In Photoacoustic imaging (PAI), the most prevalent beamforming algorithm is delay-and-sum (DAS) due to its simple implementation. However, it results in a low quality image affected by the high level of sidelobes. Coherence factor (CF) can…

Signal Processing · Electrical Eng. & Systems 2017-10-10 Moein Mozaffarzadeh , Mohammad Mehrmohammadi , Bahador Makkiabadi

Photoacoustic imaging (PAI) is a promising medical imaging modality providing the spatial resolution of ultrasound (US) imaging and the contrast of pure optical imaging. For linear-array PAI, a beamformer has to be used as the…

Medical Physics · Physics 2018-02-15 Moein Mozaffarzadeh , Yan Yan , Mohammad Mehrmohammadi , Bahador Makkiabadi

The complete characterization of spatial coherence is difficult because the mutual coherence function is a complex-valued function of four independent variables. This difficulty limits the ability of controlling and optimizing spatial…

Fourier imaging is an indirect imaging method which records the diffraction pattern of the object scene coherently in the focal plane of the imaging system and reconstructs the image using computational resources. The spatial resolution,…

Optics · Physics 2023-06-05 Hui Yuan , Alvydas Lisauskas , Mark D. Thomson , Hartmut G. Roskos

A new physically based method to estimate hemispheric-directional reflectance factor (HDRF) from lightweight multispectral cameras that have a downwelling irradiance sensor is presented. It combines radiometry with photogrammetric computer…

Data Analysis, Statistics and Probability · Physics 2019-05-10 Klaus Schneider-Zapp , Manuel Cubero-Castan , Dai Shi , Christoph Strecha

Conventional incoherent imaging based on measuring the spatial intensity distribution in the image plane faces the resolution hurdle described by the Rayleigh diffraction criterion. Here, we demonstrate theoretically using the concept of…

In absence of a lens to form an image, incoherent or partially coherent light scattering off an obstructive or reflective object forms a broad intensity distribution in the far field with only feeble spatial features. We show here that…

This paper investigates a case study on measuring and controlling the first-order degree of spatial coherence under different coupling adjustments in the storage ring. The experimental findings are consistent with the predicted inverse…

Accelerator Physics · Physics 2026-04-30 Y. Y. Sigari , N. A. Simonson , N. Appathurai , R. Castle , B. D. Moreno , S. Saadat , J. Wang , J. M. Vogt , M. J. Boland

Proposed, justified and tested measuring of beam spatial coherence, based on the detection of an interference visibility of the equal to intensity of beam replicas emerging under reflection from the rotated plane-parallel plate. The method…

Optics · Physics 2015-10-20 E. A. Tikhonov , A. K. Lyamets

Rayleigh's criterion states that it becomes essentially difficult to resolve two incoherent optical point sources separated by a distance below the width of point spread functions (PSF), namely in the subdiffraction limit. Recently,…

Quantum Physics · Physics 2019-01-09 Sisi Zhou , Liang Jiang

The investigation of the static and dynamic structural properties of colloidal systems relies on techniques capable of atomic resolution in real space and femtosecond resolution in time. Recently, the cross-correlation function (CCF)…

Other Condensed Matter · Physics 2015-11-20 Tatiana Latychevskaia , Giulia Fulvia Mancini , Fabrizio Carbone

Coherence spectroscopy has been intensively studied over the last several decades for various applications in science and engineering. The Rayleigh criterion defines the resolution limit of an interferometer, where many-wave interference…

Quantum Physics · Physics 2024-05-22 Byoung S. Ham

We present a simple yet effective method for 3D correspondence grouping. The objective is to accurately classify initial correspondences obtained by matching local geometric descriptors into inliers and outliers. Although the spatial…

Computer Vision and Pattern Recognition · Computer Science 2020-07-22 Jiaqi Yang , Jiahao Chen , Zhiqiang Huang , Siwen Quan , Yanning Zhang , Zhiguo Cao

Phase aberration is an inherent side effect of ultrasound imaging due to the speed of sound inhomogeneity nature of human tissues, resulting in focusing error and reduced image contrast. This work introduces a phase aberration correction…

Signal Processing · Electrical Eng. & Systems 2023-08-29 Wei-Hsiang Shen , Yu-An Lin , Pai-Chi Li , Meng-Lin Li

Frequency diverse array (FDA) differs from conventional array techniques in that it imposes an additional frequency offset (FO) across the array elements. The use of FO provides the FDA with the controllable degree of freedom in range…

Signal Processing · Electrical Eng. & Systems 2022-12-21 Wenkai Jia , Wen-Qin Wang , Shungsheng Zhang

Multivariate spatial field data are increasingly common and whose modeling typically relies on building cross-covariance functions to describe cross-process relationships. An alternative viewpoint is to model the matrix of spectral…

Statistics Theory · Mathematics 2015-05-07 William Kleiber

It is widely believed that range resolution, the ability to distinguish between two closely situated targets, depends inversely on the bandwidth of the transmitted radar signal. Here we demonstrate a different type of ranging system, which…

Signal Processing · Electrical Eng. & Systems 2021-06-30 Rony Komissarov , Vitali Kozlov , Dmitry Filonov , Pavel Ginzburg

The dipole cutoff behavior for the proton form factor has been and still is one of the major issues in high-energy physics. It is shown that this dipole behavior comes from the coherence between the Lorentz contraction of the proton size…

High Energy Physics - Phenomenology · Physics 2015-03-03 Young S. Kim

This paper aims to explore the feasibility of the spectrum sharing between the communication and radar system. We investigate the full-duplex (FD) joint radar and communication multi-antenna system in which a node labeled ComRad with a dual…

Information Theory · Computer Science 2022-10-25 Yinghong Guo , Cheng Li , Chaoxian Zhang , Yao Yao , Bin Xia

Noise radars can be understood in terms of a correlation coefficient which characterizes their detection performance. Although most results in the literature are stated in terms of the signal-to-noise ratio (SNR), we show that it is…

Signal Processing · Electrical Eng. & Systems 2022-04-19 David Luong , Bhashyam Balaji , Sreeraman Rajan
‹ Prev 1 2 3 10 Next ›