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Radio frequency interference (RFI) and malicious jammers are a significant problem in our wireless world. Detecting RFI or jamming is typically performed with model-based statistical detection or AI-empowered algorithms that use an input…

Signal Processing · Electrical Eng. & Systems 2025-07-29 Christos Ntemkas , Antonios Argyriou

We present an in-situ antenna characterization method and results for a "low-frequency" radio astronomy engineering prototype array, characterized over the 75-300 MHz frequency range. The presence of multiple cosmic radio sources,…

The growing need for electromagnetic spectrum to support the next generation (xG) communication networks increasingly generate unwanted radio frequency interference (RFI) in protected bands for radio astronomy. RFI is commonly mitigated at…

Signal Processing · Electrical Eng. & Systems 2022-11-01 Shuvam Chakraborty , Gregory Hellbourg , Maqsood Careem , Dola Saha , Aveek Dutta

LOFAR, the Low-Frequency Array, is a powerful new radio telescope operating between 10 and 240 MHz. LOFAR allows detailed sensitive high-resolution studies of the low-frequency radio sky. At the same time LOFAR also provides excellent short…

A selection of statistically stable (robust) algorithms for data variance calculating has been made. Their properties have been analyzed via computer simulation. These algorithms would be useful if adopted in radio astronomy observations in…

Instrumentation and Methods for Astrophysics · Physics 2015-03-17 P. A. Fridman

In this lecture, we describe a number of advanced gain calibration techniques. In particular, self-calibration is an important tool in interferometric imaging at all wavelengths. It allows the observer to determine and remove residual phase…

Instrumentation and Methods for Astrophysics · Physics 2018-05-15 Crystal L. Brogan , Todd R. Hunter , Ed B. Fomalont

We present a project to implement a national common strategy for the mitigation of the steadily deteriorating Radio Frequency Interference (RFI) situation at the Italian radio telescopes. The project involves the Medicina, Noto, and…

A radio interferometer uses time delays to maximize its response to radiation coming from a particular direction. These time delays compensate for differences in the time of arrival of the wavefront at the different elements of the…

Instrumentation and Methods for Astrophysics · Physics 2020-04-08 P. Salas , M. A. Brentjens , D. D. Bordenave , J. B. R. Oonk , H. J. A. Röttgering

Several post-detection approaches to the mitigation of radio-frequency interference (RFI) are compared by applying them to the strong RFI from the Iridium satellites. These provide estimates for the desired signal in the presence of RFI, by…

Instrumentation and Methods for Astrophysics · Physics 2019-04-02 Avinash A. Deshpande , B. M. Lewis

The rapid proliferation of low Earth orbit (LEO) satellite constellations has introduced a new class of radio frequency interference (RFI) that poses a fundamental challenge to modern radio astronomy. In particular, unintended…

Instrumentation and Methods for Astrophysics · Physics 2026-04-20 Yujin Kim

This decade, the Square Kilometre Array (SKA) will perform its first observations. Preparations for building dishes, antennas, correlators and infrastructure are well underway. Concurrently, software for the processing of SKA observations…

Instrumentation and Methods for Astrophysics · Physics 2020-11-02 H. Spreeuw , S. Yatawatta , B. Van Werkhoven , F. Diblen

With their wide fields of view and often relatively long coverage of any position in the sky in imaging survey mode, modern radio telescopes provide a data stream that is naturally suited to searching for rare transients. However, Radio…

Radio Frequency Interference (RFI) is one of the systematic challenges preventing 21cm interferometric instruments from detecting the Epoch of Reionization. To mitigate the effects of RFI on data analysis pipelines, numerous inpaint…

Energy consumption and hardware cost of signal digitization together with the management of the resulting data volume form serious issues for high-rate measurement systems with multiple sensors. Switching to binary sensing front-ends…

Instrumentation and Methods for Astrophysics · Physics 2019-07-16 Manuel S. Stein

The ionosphere is the main driver of a series of systematic effects that limit our ability to explore the low frequency (<1 GHz) sky with radio interferometers. Its effects become increasingly important towards lower frequencies and are…

Instrumentation and Methods for Astrophysics · Physics 2018-08-08 F. de Gasperin , M. Mevius , D. A. Rafferty , H. T. Intema , R. A. Fallows

We describe and compare several post-correlation radio frequency interference classification methods. As data sizes of observations grow with new and improved telescopes, the need for completely automated, robust methods for radio frequency…

Instrumentation and Methods for Astrophysics · Physics 2010-07-14 A. R. Offringa , A. G. de Bruyn , M. Biehl , S. Zaroubi , G. Bernardi , V. N. Pandey

We describe a method for spectral cleaning and timing calibration of short voltage time series data from individual radio interferometer receivers. It makes use of the phase differences in Fast Fourier Transform (FFT) spectra across antenna…

Instrumentation and Methods for Astrophysics · Physics 2016-05-04 A. Corstanje , S. Buitink , J. E. Enriquez , H. Falcke , J. R. Hörandel , M. Krause , A. Nelles , J. P. Rachen , P. Schellart , O. Scholten , S. ter Veen , S. Thoudam , T. N. G. Trinh

As the world's largest radio telescope, the Square Kilometer Array (SKA) will provide radio interferometric data with unprecedented detail. Image reconstruction algorithms for radio interferometry are challenged to scale well with TeraByte…

Computer Vision and Pattern Recognition · Computer Science 2017-03-13 Rita Ammanouil , André Ferrari , Rémi Flamary , Chiara Ferrari , David Mary

The Square Kilometre Array (SKA) will form the largest radio telescope ever built and such a huge instrument in the desert poses enormous engineering and logistic challenges. Algorithmic and architectural breakthroughs are needed. Data is…

Instrumentation and Methods for Astrophysics · Physics 2014-11-17 Orhan Ocal , Paul Hurley , Giovanni Cherubini , Sanaz Kazemi
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