Translator Disclaimer
28 July 2010 Constructing the EVLA while operating the VLA
Author Affiliations +
Begun in 2001 with a total budget of around $100M, the Expanded Very Large Array (EVLA) project is the only major upgrade to the VLA undertaken since the interferometer was dedicated in 1980. The goal of this 11-year long project is to improve all the observational capabilities of the original VLA - except for collecting area and spatial resolution - by at least an order of magnitude. To achieve this, the 28 VLA antennas have been modernized with new digital data transmission systems that link to a new, wideband, fiber optic digital LO/IF system, and eight new sets of cooled receivers are under construction that will offer full frequency coverage from 1 to 50 GHz, with instantaneous bandwidths up to 8 GHz provided by two independent dual polarization frequency pairs. The new WIDAR correlator provided by NRAO's Canadian EVLA partner replaced the old VLA correlator in early 2010 and is currently undergoing commissioning. The long duration of the EVLA construction project coupled with the need to maintain the scientific productivity and user base of the telescope obviously precluded shutting down the old array while new infrastructure was built and commissioned. Consequently, the construction plan was based on the fundamental assumption that the old VLA would continue to operate as new EVLA capabilities gradually came online; in some cases, additional complexity had to be designed into new hardware in order to maintain transitional interoperability between the old analog and new digital systems as the latter were installed and commissioned. As construction has advanced, operations has increasingly had to coexist side by side with EVLA commissioning and verification. Current commissioning plans attempt to balance making new EVLA capabilities available to the user community as soon as they have been installed and verified, and maintaining a stable and robust end-to-end data acquisition and delivery process for the user community.
© (2010) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Robert Dickman, Mark McKinnon, Claire Chandler, Richard Perley, Michael Rupen, Joseph McMullin, Bryan Butler, Barry Clark, Kenneth Sowinski, and James Ulvestad "Constructing the EVLA while operating the VLA", Proc. SPIE 7737, Observatory Operations: Strategies, Processes, and Systems III, 773705 (28 July 2010);


The Australian SKA Pathfinder
Proceedings of SPIE (September 17 2012)
Overview of engineering activities at the SMA
Proceedings of SPIE (July 12 2008)
The expanded very large array
Proceedings of SPIE (July 28 2010)
The ALMA OT in early science: supporting multiple customers
Proceedings of SPIE (September 24 2012)
Mathematic model of the FX correlator of the Chinese VLBI...
Proceedings of SPIE (September 18 2001)

Back to Top