EVLA Computing Overview Gareth Hunt EVLA Advisory Committee 2002 June 10-11

Gareth HuntEVLA Advisory Committee 2002 June Computer Subsystems e2e Monitor and Control Correlator

Proposal Preparation and Submission Observation Preparation Observation Scheduling Monitor and Control System AntennaFeedReceiverIF System Local Oscillator Fiber Optics Transmission System Correlator Image PipelineData ArchiveData Post- Processing Figure 3.1. Principal EVLA Subsystems NRAO Data Management Group (e2e project) Canadian Partner EVLA Project Primary data flow Control and monitor flow

Gareth HuntEVLA Advisory Committee 2002 June Barry Clark’s View

Gareth HuntEVLA Advisory Committee 2002 June Progress summary M&C M&C has critical deadlines to meet in 2003 –First antenna outfitting in April 2003 The major effort has been to specify and acquire a M&C Interface Board (MIB) for the antennas The RFI requirements of the MIB have placed very tight constraints on the options –Presently one chip and one RTOS Limited success in hiring has placed a huge burden on the staff

Gareth HuntEVLA Advisory Committee 2002 June Progress summary M&C (Good News) The antenna MIB chip has been selected –Several chips delivered –A prototype board has been assembled The RTOS order was placed last week One position filled –One other offer made

Gareth HuntEVLA Advisory Committee 2002 June Progress summary M&C (Bad News) Overall design not yet in place Detailed plan for test antenna software not yet available Strategy for operating three antennas in 2004 not developed –Need to look at other Telescope control systems Three positions still unfilled –Four offers declined

Gareth HuntEVLA Advisory Committee 2002 June Correlator MIB –Less stringent RFI requirements – in a screened room –Will probably use a more standard chip and real-time Linux for MIB Initial design documents for back-end data processing are complete NRAO computer staffing complete

Gareth HuntEVLA Advisory Committee 2002 June e2e Test data archive (Storage Area Network) installed Prototype pipeline tested PDR for EVLA is July 18-19, 2002 One position filled One offer declined Two other offers (NVO, ALMA) accepted