相关论文: Space-VLBI with RadioAstron: new correlator capabi…
We describe the development of an FX style correlator for Very Long Baseline Interferometry (VLBI), implemented in software and intended to run in multi-processor computing environments, such as large clusters of commodity machines (Beowulf…
(Abridged) This thesis describes the development of DiFX, the first general-purpose software correlator for radio interferometry, and its use with the Australian Long Baseline Array (LBA) to complete the largest VLBI pulsar astrometry…
Software correlation, where a correlation algorithm written in a high-level language such as C++ is run on commodity computer hardware, has become increasingly attractive for small to medium sized and/or bandwidth constrained radio…
In this paper we discuss the characteristics and operation of Astro Space Center (ASC) software FX correlator that is an important component of space-ground interferometer for Radioastron project. This project performs joint observations of…
In-correlator techniques offer the possibility of identifying and/or excising radio frequency interference (RFI) from interferometric observations at much higher time and/or frequency resolution than is generally possible with the final…
Shanghai Astronomical Observatory has upgraded its DiFX cluster to 420 CPU cores and a 432-TB storage system at the end of 2014. An international network connection for the raw data transfer has also been established. The routine operations…
In this paper a description is given of the SFXC software correlator, developed and maintained at the Joint Institute for VLBI in Europe (JIVE). The software is designed to run on generic Linux-based computing clusters. The correlation…
The digital correlator is a crucial element in a modern radio telescope. In this paper we describe a scalable design of the correlator system for the Tianlai pathfinder array, which is an experiment dedicated to test the key technologies…
We established a new algorithm for correlation process in radio astronomy. This scheme consists of the 1st-stage Fourier Transform as a filter and the 2nd-stage Fourier Transform for spectroscopy. The "FFX" correlator stands for Filter and…
A new digital backend has been developed for the BEST-2 array at Radiotelescopi di Medicina, INAF-IRA, Italy which allows concurrent operation of an FX correlator, and a direct-imaging correlator and beamformer. This backend serves as a…
For Very Long Baseline Interferometry (VLBI), the fringe spacing is extremely narrow compared to the field of view imposed by the primary beam of each element. This means that an extremely large number of resolution units can potentially be…
One of our closest neighbours, the Andromeda Galaxy (M31) has been the subject of numerous large area studies across the entire spectrum, but so far full-disk radio surveys have been conducted only at low resolution. The new wide-field…
One major goal in fast radio burst science is to detect fast radio bursts (FRBs) over a wide field of view without sacrificing the angular resolution required to pinpoint them to their host galaxies. Wide-field detection and localization…
Field Programmable Gate Array technology (FPGA) is a highly configurable option for implementing many sophisticated signal processing tasks in Software Defined Radios (SDRs). Those types of radios are realized using highly configurable…
Obtaining pulsar parallaxes via relative astrometry (also known as differential astrometry) yields distances and transverse velocities that can be used to probe properties of the pulsar population and the interstellar medium. Large programs…
We report results of the performance evaluation of a new hardware correlator in Korea, the Daejeon correlator, developed by the Korea Astronomy and Space Science Institute (KASI) and the National Astronomical Observatory of Japan (NAOJ). We…
A new generation of radio telescopes is achieving unprecedented levels of sensitivity and resolution, as well as increased agility and field-of-view, by employing high-performance digital signal processing hardware to phase and correlate…
Radio astronomical imaging arrays comprising large numbers of antennas, O(10^2-10^3) have posed a signal processing challenge because of the required O(N^2) cross correlation of signals from each antenna and requisite signal routing. This…
DIRAC (Distributed Infrastructure with Remote Agent Control) is a general framework for the management of tasks over distributed heterogeneous computing environments. It has been originally developed to support the production activities of…
We describe the design of a correlator system for ground and space-based VLBI. The correlator contains unique signal processing functions: flexible LO frequency switching for bandwidth synthesis; 1 ms dump intervals, multi-rate digital…