14-15 May, 2002.ppt

14-15 May, 2002 Correlator - Backend System Overview Correlator – Backend System Overview Correlator-Backend Network 160 (27-32 Antennas) Minimum to 336 (48 Antennas) Correlator Connections ~50 Backend Connections Maximum Aggregate Transfer Rate of 1.6 Gbytes /sec Gbit / sec switch Backend to e2e Network Maximum Aggregate Transfer Rate of 25 Mbytes / sec ~ 50 Backend Connections Network vs. Direct Channel Attached to Archive System Observational Modes Continuum Spectral Line Pulsar Bursting Sub-array Output Data Frames 266, 32-Bit Words (1064 Bytes) 1 or More Frames per Packet Frames Include all Data Needed For Lag Set Assembly All Frames From Same Baseline go to One BE Processor Direct Correlator Data Products Antenna ID Baseband ID Sub-band ID Recirculation Block Number Frame Count Status Bits Direct Correlator Data Products Phase Bin Number Sample Valid Count Time Stamp Checksum Correlation Lag Values Correlator Lag Values In-phase and Quadrature Stored as Real And Imaginary Pairs 32-bit, 2’s Complement Integers Indirect Data State Counts (Correlator Produced) Correlator Configuration Integration Rate Processing Applications and Parameters Meta Data Needed for Formatting * 14-15 May, 2002 Correlator - Backend System Overview Correlator e2e Backend M C Major Components