Australia Telescope Users Committee - Technologies Report - May 2008

Staff changes

• Graham Moorey retired late December ’08.

• Mark Bowen is the new Front End Group leader.

• Santiago Castillo hired as a new technician.

• Yoon Chung hired as a new engineer and is working on CABB with Peter Axtens.

• Scott Saunders, firmware writer with Dick Ferris, left in Dec ’08.

Overarching issues

• Though fabrication of equipment for CABB has been ongoing and operation as a spectrometer has been proven, cross correlation with phase correction has not been achieved at the Compact Array.

• A review of the effort needed to complete CABB estimates a significant proportion of the staff engaged in the project require a further 6 -8 months to complete their tasks. This makes an October installation untenable and a realistic date is mid-January 2009. • Interface modules to make the signals from the existing centimetre receivers suitable for input to the CABB system are associated with the ATCA 20/13 and 6/3 cm Receiver Upgrade project but need to be viewed as vital to the implementation of CABB. These interface modules have had little development as the resources allocated to them have been utilised on the Parkes 13 mm Receiver project with an installation due in late May.

• The absence of these interface modules would leave the array without centimetre capability so effort on the Parkes 13 mm receiver will be slowed considerably as design engineers and technical staff redirect their effort to the modules. It is uncertain at this stage but the Parkes 13 mm receiver might still be available for observing in September.

Compact Array Broadband Backend (CABB) 1

Previously…“Given the history of the project it is difficult to predict when the full changeover can occur without having information from tests with three antennas. Our current best estimate is October 2008.”

The final production run of instrumentation is well underway.

A system test facility in the Marsfield laboratories emulates the array setup and is being used to check functionality.

DSP boards

Digitiser module

Compact Array Broadband Backend (CABB) 2

A significant amount of equipment has been installed on antennas and at the central site. We will be able to support LunaSKA observing starting on May 17 with Antennas 1, 3 and 5 . A mid-May equipment installation will equip antennas 2 and 4 with the majority of modules to make them functional. Further installations during ensuing maintenance periods will aim to allow the Stage 1, single frequency engineering system to be implemented before it is required by observers in July.

Currently, phase correction only awaits the implementation of fine delay and fringe rotation. A software test period using the antennas is envisaged after the mid-May outfitting.

equaliser

IF module

O/E RTM DSP Board

O/E RTMDSP Board

O/E RTM DSP Board

O/E RTM DSP Board

DSP Board

RTM O/E

DSP Board

RTM O/E

DSP Board

RTM O/E

DSP Board

RTM O/E

WDDM

WDDM

Local oscillator distribution (Control building)

Advanced Telecom Compute Architecture (ATCA) rack

Conversion

sampling

Electrical to optical schemeLocal

oscillator distribution (antenna)

Patch Panel

32 MHz distribution

Conversion

sampling

Electrical to optical scheme Local

oscillator distribution (antenna)WDM

Conversion

sampling

Electrical to optical schemeLocal

oscillator distribution (antenna) WDM

Conversion

sampling

Electrical to optical schemeLocal

oscillator distribution (antenna) WDM

WDM

WDM

WDM

WDM

WDM

WDM

WDM

Conversion

sampling

Electrical to optical scheme Local

oscillator distribution (antenna)WDM

Conversion

sampling

Electrical to optical scheme Local

oscillator distribution (antenna)WDM

O/E RTM DSP Board

O/E RTMDSP Board

O/E RTM DSP Board

O/E RTM DSP Board

DSP Board

RTM O/E

DSP Board

RTM O/E

DSP Board

RTM O/E

DSP Board

RTM O/E

WDDM

WDDM

O/E RTM DSP Board

O/E RTMDSP Board

O/E RTM DSP Board

O/E RTM DSP Board

DSP Board

RTM O/E

DSP Board

RTM O/E

DSP Board

RTM O/E

DSP Board

RTM O/E

WDDM

WDDM

LSCX Upgrade

Three sections:

1. OMT refit2. Interface modules for CABB3. Broadbanding the front end

• One OMT is fitted to a Compact Array antenna. Parts for two others are fabricated but await assembly and testing.• Others will be fabricated as workshop time allows.

• Interface module electrical designs are being finalised to allow technicians to procure parts and design layouts.

• A broadband L/S amplifier design has been completed and a prototype fabricated. Initial, basic testing shows it works at room temperature as modelled but it awaits more extensive room temperature and cryogenic testing.

Parkes 13 mm receiver (1)

Waiting on the conversion module and subsequently it’s integration with the completed LO module. All electronic and mechanical designs are completed and housings are being machined now.

This will require a further three weeks fabrication. All components will be on hand ready for assembly.

LO module

Parkes 13 mm receiver (2)

• Frames are undergoing surface finishing and the electronics is substantially complete.

• Discussions are underway for a trial installation at Parkes ‘sans LO and conversion’ in May/June.

• Expectation of a functioning system for September observers.

• A noise spike in the bandpass at ~18 GHz needs resolution. It is suspected the waveguide noise coupler is creating a mismatch . A transition section of waveguide may solve this problem but room temperature and cryogenic testing is required.

Cryostat internals

Control and monitor

electronics

7mm spares for Mopra upgrade

Completed for Narrabri staff to refit and now operational.

LunaSKA – looking for Ultra High Energy Neutrinos

LUNASKA team (Ron Ekers, Paul Roberts and Chris Phillips from ATNF, Clancy James and Ray Protheroe from Adelaide, and Rebecca McFadden from Melbourne) are currently using the prototype elements of the Compact Array Broadband Backend on the ATCA as a testbed to develop the highly specialised methods required to undertake radio astronomy activities in a billionth of a second.

Already, these “tests” have had a lower energy threshold than any previous such experiment, and further improvements will result with the installation of further CABB equipment.

Next observing starts 17th May

PDFB External contracts

Five systems in total are being constructed for Jodrell, Effelsburg, Sardinia, Urumqi and Miyun.

Engineers from Jodrell (1) and Urumqi (2) expected on May 26th for training and final assembly.

Testing at Parkes ~11th June.

Control computer assembly

Chassis being outfitted

ASKAP 12m test bed

Undergoing acceptance testing now

An intention for George Hobbs’ team to use it for pulsar observations with a 40 element FPA should it be ready. A single pixel feed is available if the FPA is not available.

Water Vapour Radiometers

Assessment of existing units initiated.

Phil Edwards will have more detail.

Mopra Multibeam study

Undertaken for Michael Burton of University of New South Wales.

A feed study by the ICT centre under Trevor Bird.

Looked at the required effort to fabricate a 3mm multibeam receiver through replication of the hardware used for the current receiver.

Further consideration was given to configurations required for the backend, specifically the MOPS spectrometer.

Compact Array 115 GHz Upgrade

Operations Projects

We need to keep in mind that there is the prospect of technical effort required to achieve some goals of the change in operations.

Parkes 2010

Parkes 2008

2007 2008 2009 2010

ATCA 7mm upgrade

7mm upgrade for Mopra

Parkes 13 mm receiver

PDFB3

PDFB external contracts

CABB

20/13 and 6/3 cm upgrade

ASKAP

Water Vapour Radiometers

CA Upgrade to 115 GHz

Mopra Multibeam

FPA for Parkes

Study Fabrication

or

Operations projects ??