Документ взят из кэша поисковой машины. Адрес оригинального документа : http://www.atnf.csiro.au/management/atuc/2006jun/docs/5_tech_dev.pdf Дата изменения: Fri Jun 2 04:58:11 2006 Дата индексирования: Sun Jun 27 05:10:01 2010 Кодировка: Поисковые слова: dark energy

Attachment 7.1
ATNF ATUC ME MO RANDUM To: From: Date: Subject A TUC Warwick Wils on 1 June 2006 Technology development report

Parkes 6GHz Multibeam Receiver ATNF and Jodrell Bank have collaborated in the development of a 7-beam receiver covering the 6 to 7GHz band. Adaptable to either the Parkes or Lovell telescopes, initial installation took place in January 2006 at Parkes. Although delayed by two months due to some last minute design changes brought about by a communication problem between the partners, the late installation has allowed extra capability to be added, to the extent that the receiver can now observe at two frequencies simultaneously. As a result, the large methanol maser survey, which is now under way, is also providing a parallel excited-OH survey. An initial problem with the down conversion system has been rectified, and the receiver is now performing very well. 7mm ATCA Upgrade Early results of tests of the prototype 7mm frontend components indicate that good performance can be achieved across the full 30 to 50GHz band. A complete 7mm RF chain is being added to the spare ATCA mm-wave receiver, with a view to installing this unit on antenna 6 around early July. This will allow a full on-sky evaluation of the G/T performance, a critical factor for the Ka-band spacecraft tracking application. The project is on schedule for installation by May 2007. Mopra mm-wave Receiver The new MMIC-based mm-wave receiver at Mopra now has full capability at 12mm, in addition to the 77 to 116GHz coverage at 3mm. The switched noise injection facility at 3mm has been tested and shown to be a useful addition to the calibration system of the 3mm band. Initial tests of the polarisation properties of the injected noise signal indicate that a similar system, if installed on the ATCA, would provide useful polarisation calibration at 3mm. The excellent performance of the new Mopra 3mm receiver has demonstrated that ATNF now has the capability to extend the frequency coverage of the ATCA from 105 to 115GHz. Although commitments to the 7mm upgrade would prevent this proceeding in the short term, it remains an interesting possibility for the future. Mopr a 8GHz Spectr ometer (MOPS) MOPS was installed at Mopra in mid-May. The first observing session us ing the full 8GHz bandwidth is under way. The initial wide-band c onfiguration provides 1K channels ov er each 2GHz sub-band, a factor of two down in resolution on the specified figure. It is expect ed that this will be increased to 8K c hannels in the near future. Initial results are very encouraging, with the simult aneous 8GHz cov erage providing lots of ent ertainment for the users. There are still some issues, mainly to do with the Tsys meas urement, whic h need sorting out. The design of firmware for the narrow-band, high resolution, mode is nearing completion. This is an adaption of the configuration us ed at Mopra last year. It will provide at least two tunable ~100MHz wide z oom bands per 2GHz sub-band, wit h 4K c hannels across each zoom band.

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MNRF2001 ­ ATCA Br oadband Upgrade (CABB) The redes ign of the sampler, forced upon us by the unc ertainty in the supply of the spec ial Xilinx FPGAs, is complete and a prototype is being tested. Initial results are very encouraging, with the 10GB/s output data streams looking very good. A complete test of the digit al dat a pat h, from sampler through to signal processor and including the fibre optic circuits, is planned for June. Initially the CABB prototype signal processor, the same as used in MOPS, will provide the destination for this test. Schematic design and external contractor, in China, and we ex pect Hamps on and Andrew schedule. lay out of the final CABB signal proc essor board is complet e. An India, will carry out the routing. The PCB will be manufactured, in to hav e a prototype available, in Sydney, for testing in July. Grant Brown are to be congratulated for keeping this complex task on

Pulsar Di gital Filter bank This project builds on the experience gained in the development of digital filterbanks for the CABB project. The aim is to dev elop a 1GHz bandwidth, multi-channel spectrometer/ polarimeter wit h sufficient time resolution to resolv e the fastest ms pulsars. It now appears very unlikely that the Xilinx FPGAs required to complet e the pulsar digital filterbank in its original form will ev er become available. Consequently, a decision has been made to use the new CABB signal proc essor board for the pulsar digital filterbank. Considering the status of the design and fabric ation of this board (s ee abov e), it is unlik ely that a working system will be av ailable muc h bef ore the end of this year. SKA Radi o Frequency Site Tests Continuous RFI monitoring measurements were undertaken at Mileura from January 2005. In January 2006 the ATNF mobile RFI monitoring equipment was moved to two nominal SKA station sites in W.A. for a short series of measurements. The complete set of collected RFI data was presented in a report to the international SKA project office in mid-March. Major new pr ojects The second and last stage of refurbishment of the 21cm Parkes multibeam receiver will begin in October 2006, almost two years after the first stage was completed, and almost ten years after its initial installation. The remaining original LNAs will be replaced with units produced at ATNF. New and more powerful cryodyne refrigerators will also be installed. Work has begun on the construction of a new 13mm receiver for Parkes, covering the frequency band 16 to 26 GHz. The new system will provide an improvement of approximately a factor of three in sensitivity over the system that has been available for the last decade, opening up numerous new science targets, and greatly increasing observing efficiency and science outcomes for established programs.

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