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Related papers: Multi-frequency imaging in VLBI

200 papers

Radio frequency fingerprinting (RFF) is a promising device authentication technique for securing the Internet of things. It exploits the intrinsic and unique hardware impairments of the transmitters for RF device identification. In…

Signal Processing · Electrical Eng. & Systems 2023-06-26 Yuan Zeng , Yi Gong , Jiawei Liu , Shangao Lin , Zidong Han , Ruoxiao Cao , Kaibin Huang , Khaled Ben Letaief

Multi-frequency interferometry (MFI) is well known as an accurate phase-based measurement scheme. The paper reveals the inherent relationship of the unambiguous measurement range (UMR), the outlier probability, the MSE performance with the…

Information Theory · Computer Science 2012-10-09 Li Wei , Wangdong Qi

Radio Frequency Interference (RFI) increasingly contaminates the radio astronomy spectrum, often exceeding astronomical signal amplitudes by 50-70 dB. Reliable detection and mitigation are therefore essential for studies of faint transient…

Instrumentation and Methods for Astrophysics · Physics 2026-05-08 Natalia A. Schmid , Sasanka Katreddi , Yechan Kweon

The CLEAN algorithm, widely used in radio interferometry for the deconvolution of radio images, performs well only if the raw radio image (dirty image) is, to good approximation, a simple convolution between the instrumental point-spread…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 I. M. Stewart , D. M. Fenech , T. W. B. Muxlow

This paper presents a flexible representation of neural radiance fields based on multi-plane images (MPI), for high-quality view synthesis of complex scenes. MPI with Normalized Device Coordinate (NDC) parameterization is widely used in…

Computer Vision and Pattern Recognition · Computer Science 2023-10-03 Yuze He , Peng Wang , Yubin Hu , Wang Zhao , Ran Yi , Yong-Jin Liu , Wenping Wang

The balloon-borne very long baseline interferometry (VLBI) experiment is a technical feasibility study for performing radio interferometry in the stratosphere. The flight model has been developed. A balloon-borne VLBI station will be…

In the era of big data, radio astronomical image reconstruction algorithms are challenged to estimate clean images given limited computing resources and time. This article is driven by the need for large scale image reconstruction for the…

Instrumentation and Methods for Astrophysics · Physics 2019-08-20 Rita Ammanouil , André Ferrari , David Mary , Chiara Ferrari , Francesca Loi

Multimodal medical image fusion (MMIF) extracts the most meaningful information from multiple source images, enabling a more comprehensive and accurate diagnosis. Achieving high-quality fusion results requires a careful balance of…

Computer Vision and Pattern Recognition · Computer Science 2025-06-19 Dan He , Weisheng Li , Guofen Wang , Yuping Huang , Shiqiang Liu

Traditionally VLBI observations focus on a small patch of sky and image typically a few 100 mas around a bright source, which is often used to self-calibrate the data. High spectral and time resolution is needed to image a larger area, in…

The VLTI Spectro Imager (VSI) was proposed as a second-generation instrument of the Very Large Telescope Interferometer providing the ESO community with spectrally-resolved, near-infrared images at angular resolutions down to 1.1…

The CHIME radio telescope operates in the frequency bandwidth of 400 to 800 MHz. The CHIME/FRB collaboration has a data pipeline that analyzes the data in real time, suppresses radio frequency interferences (RFI) and searches for FRBs.…

Instrumentation and Methods for Astrophysics · Physics 2023-11-21 K. J. Luke

We consider the problem of multifrequency VLBA image synthesis and spectral-index mapping for active galactic nuclei related to the necessity of taking into account the frequency-dependent image shift. We describe our generalized…

Cosmology and Nongalactic Astrophysics · Physics 2010-06-29 Anisa T. Bajkova , Alexander B. Pushkarev

There are many image fusion methods that can be used to produce high-resolution mutlispectral images from a high-resolution panchromatic (PAN) image and low-resolution multispectral (MS) of remote sensed images. This paper attempts to…

Computer Vision and Pattern Recognition · Computer Science 2011-08-17 Firouz Abdullah Al-Wassai , N. V. Kalyankar , Ali A. Al-Zaky

High precision astrometric Space Very Long Baseline Interferometry (S-VLBI) at the low end of the conventional frequency range, i.e. 20cm, is a requirement for a number of high priority science goals. These are headlined by obtaining…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 R. Dodson , M. Rioja , Y. Asaki , H. Imai , X. -Y. Hong , Z. Shen

Time-frequency images (TFIs) provide a joint time-frequency representation of a signal and have become an effective tool for analyzing, characterizing, and processing non-stationary signals. Deep learning (DL) techniques have become…

Signal Processing · Electrical Eng. & Systems 2023-02-23 Mehmet Parlak

Very long baseline interferometry (VLBI) provides the highest-resolution images in astronomy. The sharpest resolution is nominally achieved at the highest frequencies, but as the observing frequency increases so too does the atmospheric…

Functional Magnetic Resonance Imaging (fMRI) is a neuroimaging technique with pivotal importance due to its scientific and clinical applications. As with any widely used imaging modality, there is a need to ensure the quality of the same,…

Image and Video Processing · Electrical Eng. & Systems 2020-09-29 David Calhas , Rui Henriques

The advent of enhanced technologies in radio interferometry and the perspective of the SKA telescope bring new challenges in image reconstruction. One of these challenges is the spatio-spectral reconstruction of large (Terabytes) data cubes…

Instrumentation and Methods for Astrophysics · Physics 2016-03-07 Jérémy Deguignet , André Ferrari , David Mary , Chiara Ferrari

Multi-modal image fusion (MMIF) integrates valuable information from different modality images into a fused one. However, the fusion of multiple visible images with different focal regions and infrared images is a unprecedented challenge in…

Computer Vision and Pattern Recognition · Computer Science 2024-02-01 Xilai Li , Xiaosong Li , Tao Ye , Xiaoqi Cheng , Wuyang Liu , Haishu Tan

This thesis reports on the application of new wide-field Very Long Baseline Interferometry (VLBI) imaging techniques using real data for the first time. These techniques are used to target three specific science areas: (i) a…

Astrophysics of Galaxies · Physics 2014-06-19 Emil Lenc