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The initial phase of the Square Kilometre Array (SKA) [1] is represented by a −10% instrument and construction should start in 2018. SKA 1-Low, a sparse Aperture Array (AA) covering the frequency range 50 to 350 MHz, will be part of this. This instrument will consist of 512 stations, each hosting 256 antennas creating a total of 131,072 antennas. A first verification system towards SKA 1-Low, Aperture...
The Low Frequency Aperture Array (LFAA) component of the Square Kilometer Array (SKA) involves the processing of 218 signal chains, which will be performed on custom FPGA boards, the Tile Processing Module (TPM). These TPMs, as well as firmware running on them, need to be managed, monitored and controlled by the rest of the system. This requires access to on-board devices and registers on running...
A synthesis of a GA and an EM application to guide the design and optimisation of tightly coupled phased array antennas is proposed. Some analysis and tested results are provided. This technique is biased to satisfy certain desired specifications subject to the mid-frequency SKA radio astronomy. Tightly coupled arrays are a practical realisation of the current sheet model (CSA) for an array with a...
A monitoring and control system is being developed for the Aperture Array Verificaton System (AAVS) prototype of the Low Frequency Aperture Array (LFAA) component of the Squatre Kilometer Array (SKA). This software system will have to continuously monitor hundreds of thousands of antennas; schedule, run and monitor observations; control the data flow within the element and outwards; and provide the...
Analysis of the seabed composition over a large spatial scale is an interesting yet very challenging task. Apart from the field work involved, hours of video footage captured by cameras mounted on Remote Operated Vehicles (ROVs) have to be reviewed by an expert in order to classify the seabed topology and to identify potential anthropogenic impacts on sensitive benthic assemblages. Apart from being...
This paper presents the design of a wideband (50–350 MHz) low noise amplifier (LNA), employing a bandwidth constrained noise figure optimization technique targeted for a low frequency band Square Kilometer Array radio telescope. In this application, noise figure and power consumption optimization is crucial. In fact, the LNA optimization and analysis considers the effect of the induced gate noise...
In this communication Near-Field to Far-Field (NF/FF) measurements are employed to characterize the radiation pattern of a prototype of 9 × 9 finite array antenna element proposed for radio astronomy. The antenna design is a tightly coupled phased array designed to function in the 0.3 – 1.3 GHz band. The developed antenna is a composite structure to achieve ultra-wideband performance. It is likely...
As the amount of space debris orbiting the earth is continuously increasing, it is becoming essential to monitor and predict the debris' trajectories in order to avoid collision that could threaten space missions, i.e. operative satellites or manned spacecraft. An innovative bistatic radar system, that couples multi-beaming and ranging techniques, is proposed in this work as an instrument for the...
Aperture Arrays (AA) mark a new era in radio astronomy combining high sensitivity with a large field-of-view, enabling very high survey and imaging speeds. This paper describes the development of low frequency aperture arrays leading up to SKA phase 1 within the Aperture Array Verification Program (AAVP) as part of the SKA program.
In this paper, we consider the problem of optimum multi-domain real-time beamforming and high-precision beam pattern positioning in application to very large wideband array antennas, particularly to the Square Kilometre Array (SKA) aperture array antenna. We present a new structure for wideband space-frequency beamforming and beamsteering that maximizes detectability of cosmic signals over the array...
Digital beamforming for the aperture array components of the Square Kilometre Array (SKA) poses considerable computational challenges. We propose a hierarchical scheme aimed at tackling them and introduce OSKAR, a beamforming simulator which implements these ideas and algorithms. The simulator continues to be developed to investigate possible designs for the custom devices envisaged for phase 1 of...
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