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ASKAP Technical Update
CSIRO Astronomy and Space Science December 2009

The ASKAP Technical Update contains a brief summary of recent science and technical developments related to the Australian SKA Pathfinder (ASKAP) project. It documents, at a top level, recent developments and milestones reached by core CSIRO ASKAP project teams. Each issue also looks at an aspect of key ASKAP activity. Previous issues can be read online at www.atnf.csiro.au/projects/askap. Award-winning Team
For his achievements in astronomy and wireless technologies, ASKAP engineer Dr John O'Sullivan has been recognised with Australia's preeminent science award ­ the 2009 Prime Minister's Prize for Science . Dr O'Sullivan was Project Leader of CSIRO's Wireless Local Area Networ k (LAN) Research Team, a group that developed wireless LAN technology that is used in most wireless communication systems. This technology is used by over 800 million people ever y day. The wireless LAN stor y can be traced back to Dr O'Sullivan's wor k in astronomy and his application of mathematical equations called Fourier transforms to help eliminate the problems posed by multipath transmission in astronomical data. Dr O'Sullivan's latest effor ts are directed towards the development of an innovative radio camera, or phased array feed, for ASKAP. By going back to fir st principles, Dr O'Sullivan has developed a novel "chequerboard" design for the phased array feed for ASKAP's 36 antennas. The receive-only phased array feeds, using multiple simultaneous electronic beams, will be housed at the focal point of the antennas' parabolic reflector dishes to provide an instantaneous wide field-of-view of the sky. Dr O'Sullivan's wor k has increased ASKAP's information gathering potential by more than an order of magnitude, which is central to achieving transformational science with the telescope, and also has the potential to influence the design of the SKA.

IPT Progress Update
ASKAP's Integrated Project Teams have been reaching key milestones and progressing towards successful deliver y of the project.

ASKAP Antennas
Factor y acceptance testing of ASKAP's fir st antenna was successfully completed at manufacturer CETC54's antenna range in September 2009. The fir st antenna was then dismantled, painted and transpor ted to Fremantle, in preparation for its installation at the Murchison Radio-astronomy Obser vator y in December 2009 and Januar y 2010. Designs for the antenna's temporar y constr uction switchboard and prototype smar t switchboard have been approved and manufacture is in progress. The smar t swicthboard will allow exact metering of antenna energy usage and remote control of power.

ASKAP Analog Systems
The mechanical design of the ASKAP prime focus receiver package is nearing completion and some par ts have already been sent for production. Prototyping of the receiver electronics is progressing well with the design of all the main circuit boards, which typically ser ve four to eight receiver channels, now complete. Manufacture of the fir st prototype of one of the circuit boards is complete and testing has commenced. The results from the initial tests are good and more thorough testing is now being carried out. > Dr John O'Sullivan with a prototype of the revolutionary phased array feed for ASKAP. Photo credit: Chris Walsh, Patrick Jones Photo Studio.


ASKAP Digital Systems
The digital systems prototype hardware has been integrated with initial firmware and is producing good test results. These results were presented at a critical design review attended by three international reviewer s from ASTRON (The Nether lands), the SKA Project Development Office (UK), and Dominion Radio Astrophysical Obser vator y (Canada). The initial design, with a few modifications, has been put into production for the fir st ASKAP antenna. This hardware has star ted arriving and integration and testing is in progress. Digital 10 Gbps XAUI communications has been established between the antenna processing equipment and the central site beamformer hardware. Fur ther test fixtures are in development for the testing of the AdvancedTC A shelf at the central ASKAP site.

while the firmware continues to be developed. A production r un of 30 synthesiser cards is currently underway. A new small aper ture satellite terminal (VSAT) and initial networ k have been installed at Boolardy Homestead, and the capacity of the antenna site office VSAT has been upgraded to 1Mb up/4 Mb down. The VSATs will play an impor tant role in remote-site communications until the long-haul fibre cable between Geraldton and the Murchison Radioastronomy Obser vator y is completed.

ASKAP Science and User Policy
In September 2009 CSIRO announced that ten major science projects, representing 363 unique author s from 131 institutions, had been selected to use ASKAP during the fir st five year s of the telescope's operation. The large Sur vey Science Projects, each needing more than 1500 hour s to complete and designed to take advantage ASKAP's unique capabilities, will use at least 75 per cent of the telescope's obser ving time. Representatives of the ten projects have been invited to wor k with CSIRO through the Design Studies phase.

ASKAP MRO Related Activities
Official registration of an Indigenous Land Use Agreement (ILUA) signed between the Yamatji Mar lpa Aboriginal Corporation, the Wajarri Yamatji People, the Government of Western Australia, Australian Government and CSIRO took place in November 2009. The ILUA means that CSIRO's lease over the Murchison Radio-astronomy Obser vator y (MRO) has taken effect and that constr uction of ASKAP may begin. The tender for MRO suppor t infrastr ucture design has been awarded, design of the fir st antenna foundation has been completed, and the telehandler (a specialised crane) to be used for constr uction and maintenance of ASKAP's antennas has arrived on site.

SKA Related Activities
CSIRO staff par ticipated several international meetings held in November 2009 in Manchester, UK, which aimed to provide a snapshot of the wor ld-wide progress towards the design of the SKA. CSIRO has engaged BAE Systems Australia to provide critical analyses of the performance of its phased array feed receiver s within the proposed SKA antenna design, and signed a statement of intent to wor k with IBM on a prototype single digital backend for the SKA.
For further information: G a b by R u s s e l l Communication O f ficer CSI RO Aus tr alia Telescope National Facili t y Phone: +61 2 9372 4339 Email: gabby. r ussell @ csir o. au Web: w w w. atnf.csir o. au /pr ojec t s /a sk ap

ASKAP Computing
In November 2009 integrating and testing of several key software components was successfully completed. Development of imaging and science analysis software is progressing well, with the successful r unning of end-to-end simulations for continuum and spectral line data. Software ver sion 1.1 for monitoring and controlling the Par kes Testbed Facility's 12-metre antenna has been released, with new features including scripting of obser vations and the ability to capture the array covariance matrix.

ASKAP System Engineering, Integration and Commissioning
Testing and characterisation of ASKAP's prototype phased array feed (PAF) has continued. Two separate week-long campaigns of intensive testing of the PAF took place on the Par kes Testbed Facility's 12-metre antenna in October and December 2009. Analysis of the results is continuing and the PAF will be removed from the antenna for fur ther ground testing. Development of SAPKAP, the full scale ASKAP antenna model located at CSIRO's Mar sfield site, has continued with the addition of quadripod legs and the mechanical interface between the antenna and the holography receiver. The latter will be used to verify the surface accuracy and performance of the real antennas during acceptance testing.

ASKAP Data and Signal Transport
The antenna frequency synthesiser s (PLL units), reference clean-up loop and RF optical interface have now been combined with the monitor control serial peripheral interface (SPI) and a digital systems controller card. This new single chassis, dubbed the RSL (reference, SPI, local oscillator), will also be able to provide direct ethernet connectivity to the antenna networ k switch as well as provide binar y atomic time demodulation for precision event synchronisation. The monitor control unit and DC control card for the phased array feed are close to manufacture ,