The Square Kilometre Array: An Engineering Perspective

The Square Kilometre Array (SKA) Project is a global project to design and c- struct a revolutionary new radio telescope with of order 1 million square meters of collecting area in the wavelength range from3mto1cm.It will have two - ders of magnitude greater sensitivity than current telescopes and an unprecedented large instantaneous ?eld-of-view. These capabilities will ensure the SKA will play a leading role in solving the major astrophysical and cosmological questions of the day (see the science case at skatelescope.org/pages/page astronom.htm). The SKA will complement major ground- and space-based astronomical facilities under construction or planned in other parts of the electromagnetic spectrum (e.g. ALMA, JWST, ELT, XEUS,...). The current schedule for the SKA foresees a decision on the SKA site in 2006, a decisiononthedesignconceptin2009,constructionofthe?rstphase(international path?nder)from2010to2013,andconstructionofthefullarrayfrom2014to2020. The cost is estimated to be about 1000 M . TheSKAProjectcurrentlyinvolves45institutesin17countries,manyofwhich are involved in nationally- or regionally-funded state-of-the-art technical devel- ments being pursued ahead of the 2009 selection of design concept. This Special Issue of Experimental Astronomy provides a snapshot of SKA engineering act- ity around the world, and is based on presentations made at the SKA meeting in Penticton,BC,CanadainJuly2004.Topicscoveredincludeantennaconcepts,so- ware, signal transport and processing, radio frequency interference mitigation, and reports on related technologies in other radio telescopes now under construction. Further information on the project can be found at skatelescope.org.

The Square Kilometre Array (SKA) Project is a global project to design and c- struct a revolutionary new radio telescope with of order 1 million square meters of collecting area in the wavelength range from3mto1cm.It will have two - ders of magnitude greater sensitivity than current telescopes and an unprecedented large instantaneous ?eld-of-view. These capabilities will ensure the SKA will play a leading role in solving the major astrophysical and cosmological questions of the day (see the science case at skatelescope.org/pages/page astronom.htm). The SKA will complement major ground- and space-based astronomical facilities under construction or planned in other parts of the electromagnetic spectrum (e.g. ALMA, JWST, ELT, XEUS,...). The current schedule for the SKA foresees a decision on the SKA site in 2006, a decisiononthedesignconceptin2009,constructionofthe?rstphase(international path?nder)from2010to2013,andconstructionofthefullarrayfrom2014to2020. The cost is estimated to be about 1000 M . TheSKAProjectcurrentlyinvolves45institutesin17countries,manyofwhich are involved in nationally- or regionally-funded state-of-the-art technical devel- ments being pursued ahead of the 2009 selection of design concept. This Special Issue of Experimental Astronomy provides a snapshot of SKA engineering act- ity around the world, and is based on presentations made at the SKA meeting in Penticton,BC,CanadainJuly2004.Topicscoveredincludeantennaconcepts,so- ware, signal transport and processing, radio frequency interference mitigation, and reports on related technologies in other radio telescopes now under construction. Further information on the project can be found at skatelescope.org.

The Square Kilometre Array (SKA) Project is a global project to design and c- struct a revolutionary new radio telescope with of order 1 million square meters of collecting area in the wavelength range from3mto1cm.It will have two - ders of magnitude greater sensitivity than current telescopes and an unprecedented large instantaneous ?eld-of-view. These capabilities will ensure the SKA will play a leading role in solving the major astrophysical and cosmological questions of the day (see the science case at skatelescope.org/pages/page astronom.htm). The SKA will complement major ground- and space-based astronomical facilities under construction or planned in other parts of the electromagnetic spectrum (e.g. ALMA, JWST, ELT, XEUS,...). The current schedule for the SKA foresees a decision on the SKA site in 2006, a decisiononthedesignconceptin2009,constructionofthe?rstphase(international path?nder)from2010to2013,andconstructionofthefullarrayfrom2014to2020. The cost is estimated to be about 1000 M . TheSKAProjectcurrentlyinvolves45institutesin17countries,manyofwhich are involved in nationally- or regionally-funded state-of-the-art technical devel- ments being pursued ahead of the 2009 selection of design concept. This Special Issue of Experimental Astronomy provides a snapshot of SKA engineering act- ity around the world, and is based on presentations made at the SKA meeting in Penticton,BC,CanadainJuly2004.Topicscoveredincludeantennaconcepts,so- ware, signal transport and processing, radio frequency interference mitigation, and reports on related technologies in other radio telescopes now under construction. Further information on the project can be found at skatelescope.org.

The Square Kilometre Array: An International Engineering Perspective.- The Allen Telescope Array.- Sky Noise Limited Snapshot Imaging in the Presence of RFI with LOFAR’s Initial Test Station.- The LOFAR Central Processing Facility Architecture.- Hemispheric Imaging of Galactic Neutral Hydrogen with a Phased Array Antenna System.- Electronic Multi-Beam Radio Astronomy Concept: Embrace a Demonstrator for the European SKA Program.- The Australian SKA New Technology Demonstrator Program.- Low Noise Performance Perspectives of Wideband Aperture Phased Arrays.- Effective Sensitivity of a Non-Uniform Phased Array of Short Dipoles.- Low Frequency End Performance of a Symmetrical Configuration Antenna for the Square Kilometre Array (SKA).- Radio Astronomy Antennas by the Thousands.- A Spherical Lens for the SKA.- Efficiency Analysis of Focal Plane Arrays in Deep Dishes.- Model Validation and Performance Evaluation for the Multi-Tethered Aerostat Subsystem of the Large Adaptive Reflector.- Modeling of a Feed Support System for Fast.- Cylindrical Reflectors.- Local Oscillator Distribution Using a Geostationary Satellite.- RF Design of a Wideband CMOS Integrated Receiver for Phased Array Applications.- Fiber Optic Network Technology for Distributed Long Baseline Radio Telescopes.- ALMA and e-MERLIN Data Transmission Systems: Lessons for SKA.- Array Signal Processing for Radio Astronomy.- Ska Correlator Advances.- RFI Mitigation and the SKA.- A 256 MHz Bandwidth Baseband Receiver/Spectrometer.- The Square Kilometre Array Molonglo Prototype (SKAMP) Correlator.- COTS Correlator Platform.- DSN Deep-Space Array-Based Network Beamformer.- Software Development for the Square Kilometre Array.- A Simple Model of Software Costs for the Square Kilometre Array.- SKA and EVLA Computing Costsfor Wide Field Imaging.- Efficient Imaging Strategies for Next-Generation Radio Arrays.- System Optimisation of Multi-Beam Aperture Synthesis Arrays for Survey Performance.- SKA Cost Model for Wide Field-of-View Options.- Cost Effective Frequency Ranges for Multi-Beam Dishes, Cylinders, Aperture Arrays, and Hybrids.- Cylinder — Small Dish Hybrid for the SKA.- RFI Test Observations at a Candidate SKA Site in China.