SKA LFAA Station Design Report

Eloy de Lera Acedo; Hardie Pienaar; Nima Razavi Ghods; Jens Abraham; Edgar Colin Beltran; Ben Mort; Fred Dulwich; Giuseppe Virone; Benedetta Fiorelli; Michiel Arts; Christophe Craeye; Bui van Ha; Keith Grainge; Peter Dewdney; Jeff Wagg; Maria Grazia Labate; Andrew Faulkner; Jan Geralt bij de Vaate; Marchel Gerbers

arXiv · 2003.12744

SKA LFAA Station Design Report

Eloy de Lera Acedo·Hardie Pienaar·Nima Razavi Ghods·Jens Abraham·Edgar Colin Beltran·Ben Mort·Fred Dulwich·Giuseppe Virone·Benedetta Fiorelli·Michiel Arts·Christophe Craeye·Bui van Ha·Keith Grainge·Peter Dewdney·Jeff Wagg·Maria Grazia Labate·Andrew Faulkner·Jan Geralt bij de Vaate·Marchel Gerbers

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Abstract

This report was submitted as part of the SKA Low Frequency Aperture Array Critical Design Review describing the design of the SKA1-LOW station that took place between 2013 and 2018. The SKA1 LOW field station is inscribed in a circular area having an effective station diameter (centre to centre) of 38 meters and has 256 SKALA4 elements. This document describes the electromagnetic design of the field station. In particular it describes the layout design and the electromagnetic modelling and characteristics of the station. This document describes the effects associated with the layout and array such as mutual coupling effects, side lobe pattern and beam shape (eg. smoothness, calibration models) and presents the state of the art of our ability to measure the array performance and validate the simulation work. The current LFAA field node requirements, derived from the SKA L1 requirements, have evolved over the last years since the LFAA PDR and the System Baseline Design. The SKA1 LOW field station has been designed to meet those requirements and has therefore tracked their evolution (eg. sensitivity requirements, array diameter, etc.). The aforementioned requirements represent a very tight space with a desire for very high sensitivity over a large frequency range (7 to 1) and wide field of view (90 degrees cone around zenith) while keeping the station diameter to a minimum, so as the filling factor but at the same time allowing for sufficient space between antennas to allow for easy maintenances, amongst many others. This results in a complex design.

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Eloy de Lera Acedo, Hardie Pienaar, Nima Razavi Ghods, Jens Abraham, Edgar Colin Beltran, Ben Mort, Fred Dulwich, Giuseppe Virone, Benedetta Fiorelli, Michiel Arts, Christophe Craeye, Bui van Ha, Keith Grainge, Peter Dewdney, Jeff Wagg, Maria Grazia Labate, Andrew Faulkner, Jan Geralt bij de Vaate, Marchel Gerbers. 2020-03-28. SKA LFAA Station Design Report. https://arxiv.org/abs/2003.12744

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