A5064483165- Radio Astronomy Observations and Technology
- Antenna Design and Optimization
- Astrophysics and Cosmic Phenomena
- Electromagnetic Compatibility and Measurements
- Superconducting and THz Device Technology
- Radio Wave Propagation Studies
- Advanced Photonic Communication Systems
- Microwave Engineering and Waveguides
- Antenna Design and Analysis
- Soil Moisture and Remote Sensing
- Space Science and Extraterrestrial Life
- Solar and Space Plasma Dynamics
- Cosmology and Gravitation Theories
- Optical Network Technologies
- Astronomy and Astrophysical Research
- Planetary Science and Exploration
- Adaptive optics and wavefront sensing
- Geophysics and Gravity Measurements
- Distributed and Parallel Computing Systems
- Satellite Communication Systems
- Semiconductor Lasers and Optical Devices
- Scientific Research and Discoveries
- Spacecraft Design and Technology
- Astronomical Observations and Instrumentation
- Optical Wireless Communication Technologies
National Institute for Astrophysics
2014-2024
Istituto di Radioastronomia di Bologna
2011-2022
Arcetri Astrophysical Observatory
2018
Netherlands Institute for Radio Astronomy
2011
I.R.C.C.S. Oasi Maria SS
2001-2011
Institute of Atmospheric Sciences and Climate
2009
Bologna Research Area
2003-2005
National Academies of Sciences, Engineering, and Medicine
2000
This letter presents a radiation pattern verification system for low-frequency antennas in their operative conditions, e.g., on the ground, next to other elements, etc. It is far-field setup using properly equipped micro unmanned aerial vehicle (UAV) as test source. The UAV can perform an autonomous flight. Its absolute position measured with remote topographic instrument. By data processing, received power along flying path reconstructed. proposed has been validated two standard wire at 150...
An active dual-polarized Log-Periodic antenna has been designed to meet the requirements of low-frequency (50 - 350 MHz) radio telescope Square Kilometre Array (SKA). The integration and low noise amplifier conceived in order achieve a high degree testability. This aspect found be crucial obtain smooth frequency response compatible with SKA science cases. design also driven by other factors such as large-volume production (more than 130 000 antennas will built) environmental conditions harsh...
In this paper, a new version of the field-mill sensor structure for atmospheric electric field measurements is presented. Both hardware components (i.e., mechanical structure, electronic front end, and acquisition control systems) data processing software are designed in order to reduce power consumption enhance instrument metrological performance terms accuracy, sensitivity, frequency band.
In this paper we present the electromagnetic modeling and beam pattern measurements of a 16-elements ultra wideband sparse random test array for low frequency instrument Square Kilometer Array telescope. We discuss importance small platform development technologies techniques towards final telescope, highlighting most relevant aspects its design. also describe simulations work as well embedded-element using an Unmanned Aerial Vehicle system. The latter are helpful both validation models...
ABSTRACT Two meteorite pieces have been recovered in Italy, near the town of Cavezzo (Modena), on 2020 January 4th. The associated fireball was observed evening New Year’s Day by eight all-sky cameras PRISMA network, a partner FRIPON. computed trajectory had an inclination angle approximately 68° and velocity at infinity 12.8 km s−1. Together with relatively low terminal height, estimated as 21.5 km, those values were indicating significant possibility dropping event, additionally confirmed...
The design and development process for the Square Kilometre Array (SKA) radio telescope’s Low Frequency Aperture component was progressed during SKA pre-construction phase by an international consortium, with goal of meeting requirements a critical review. As part full-sized prototype ‘station’ deployed – Verification System 1 (AAVS1). We provide system overview describe commissioning results AAVS1, which is low frequency telescope 256 dual-polarisation log-periodic dipole antennas working...
The low frequency component of the Square Kilometre Array (SKA1-Low) will be an aperture phased array located at Murchison Radio-astronomy Observatory (MRO) site in Western Australia. It composed 512 stations, each consisting 256 log-periodic dual-polarized antennas, and operate range (50 to 350 MHz) SKA bandwidth. Aperture Verification System 2 (AAVS2), operational since late 2019, is last full-size engineering prototype station deployed MRO before start SKA1-Low construction phase. aim...
Front-end amplifiers with high input impedance are exploited to build active array elements for modern low-frequency radio telescopes. The combination of such loading and mutual coupling between adjacent is responsible the deep nulls that present in some embedded element patterns (EEPs) Low-Frequency Array. This paper quantifies this phenomenon both models experimental data. full-wave simulations measured amplifier scattering parameters combined obtain EEP models. These good agreement situ...
Abstract This paper describes two small aperture array demonstrators called Medicina and Sardinia Array Demonstrators (MAD SAD, respectively). The objectives of these instruments are to acquire experience test new technologies for a possible application the low‐frequency telescope Square Kilometer phase 1 (SKA1‐LOW). MAD was concluded in 2014, it turned out be an important bench implementing calibration techniques based on artificial source mounted aerial vehicle. SAD is 128 dual‐polarized...
A novel antenna pattern measurement technique has been recently developed exploiting the capabilities of a micro Unmanned Aerial Vehicle (UAV) as far-field test-source. This is suitable for characterizing VHF antennas such those low-frequency radio astronomy. paper presents some measurements performed on Square Kilometer Array Log-periodic Antenna (SKALA), which selected receiving element Low Frequency Aperture (LFAA).
A signal processing hardware platform has been developed for the Low Frequency Aperture Array component of Square Kilometre (SKA). The board, called an Analog Digital Unit (ADU), is able to acquire and digitize broadband (up 500[Formula: see text]MHz bandwidth) radio-frequency streams from 16 dual polarized antennas, channel data then combine them flexibly as part a larger beamforming system. It envisaged that there will be more than 8000 these platforms in first phase SKA, so particular...
The characterization of VHF and UHF antennas is very challenging owing to the low-operative frequency. This paper presents a novel technique (originally developed for radio-astronomical applications) that can be suitable measure ground-based aerospace in real installation conditions, with an accurate cost-effective method which does not require additional infrastructures. system mainly consists micro Unmanned Aerial Vehicle (UAV), equipped both RF transmitter antenna, properly designed...
The Square Kilometre Array telescope at low-frequency (SKA-Low) will be a phased array supporting wide range of science cases covering the frequency band 50 - 350 MHz, while same time asking for high sensitivity and excellent characteristics. These extremely challenging requirements resulted in design using 512 groups 256 log periodic dual polarized antennas each (where group is called "station"), total 131072 antennas. stations are randomly distributed mostly within dense area around centre...
This paper overviews the emerging antenna and EM field measurement strategies based on modern Unmanned Aerial Vehicle (UAV) technology. UAVs are currently being exploited as source/probe positioners in various applications from HF to microwaves. Several contributions all-over world will be discussed terms of approach, RF setup positioning strategies. A example at 350 MHz highlights importance position orientation accuracy post-processing chain.
The signal reception chain is an essential element for achieving the square kilometer array-low (SKA-low) system requirements in terms of high sensitivity and dynamic range. balance between gain, linearity, low power consumption, as well cost, are fundamental parameters that influence selection most suitable technology SKA-low. Further factors, such self-generated radio frequency (RF) interference, reliability, robustness under extreme environment, last but not least, distance antennas...
We present the status of Sardinia Radio Telescope (SRT) project, a new general purpose, fully steerable 64 m diameter parabolic radiotelescope capable to operate with high efficiency in 0.3-116 GHz frequency range. The instrument is result scientific and technical collaboration among three Structures Italian National Institute for Astrophysics (INAF): Astronomy Bologna, Cagliari Observatory (in Sardinia,) Arcetri Astrophysical Florence. Funding agencies are Ministry Education Scientific...
A large-bandwidth, state-of-the-art multi-feed receiver has been constructed to be used on the new 64 m Sardinia Radio Telescope (SRT) (http://www.srt.inaf.itl), an antenna aiming work from 300 MHz 100 GHz with almost continuous frequency coverage. The goal of this is speed up survey sky high sensitivity in a band that very interesting radio astronomers. In meantime, erection finalized, and mounted Medicina 32 tested (http://www.med.ira.inaf.itl). We present complete description system,...
The Unmanned Aerial Vehicle (UAV) technology has been recently used to develop a pattern measurement system for low-frequency arrays in their real installation conditions. This paper presents the most important results that have obtained on Italian Medicina Array Demonstrator (MAD).
This paper deals with the electromagnetic modeling of a dipole antenna mounted on micro Unmanned Aerial Vehicle (UAV). Such setup has been recently used as test source to characterize radiation pattern fairly large VHF and UHF antennas in their installation conditions i.e. ground, adjacent elements. In this framework, an accurate is fundamental distinguish properly its characteristics from those under test. The computed results are verified both reflection coefficient measurements showing...
Low frequency aperture array technology requires advanced ad-hoc tools for performing antenna and pattern characterization instrumental calibration. A micro Unmanned Aerial Vehicle (UAV) mounting a radio-frequency transmitting system developed in Italy has demonstrated to satisfy the challenging characteristics of these tasks. Therefore, measurement campaign by means this UAV been planned one Dutch station Frequency Array (LOFAR) with main goal improve LOFAR models. In preparation campaign,...
Abstract We present the first Southern-Hemisphere all-sky imager and radio-transient monitoring system implemented on two prototype stations of low-frequency component Square Kilometre Array (SKA-Low). Since its deployment, has been used for real-time recorded commissioning data. Additionally, a transient searching algorithm executed resulting images. It uses difference imaging technique to enable identification wide variety classes, ranging from human-made radio-frequency interference...
We present the Engineering Development Array 2, which is one of two instruments built as a second generation prototype station for future Square Kilometre Low-Frequency Array. The array comprised 256 dual-polarization dipole antennas that can work phased or standalone interferometer. describe design and details changes from previous instruments, well motivation changes. Using an imaging interferometer, we measure sensitivity at five frequencies ranging 70 to 320 MHz.
The computational electromagnetic modelling of a large radio telescope prototype array for the Square Kilometer Array is described. numerical models, using Method Moments, are characterised by very number unknowns, requiring use fast solution methods and high performance computing platforms. Good agreement has been obtained between results on two different commercial codes. Results both embedded element patterns station beam shown. computed calibration briefly addressed.