Download presentation
Presentation is loading. Please wait.
Published byLouisa Harrell Modified over 9 years ago
1
APSR Matthew Bailes Swinburne University Of Technology
2
Baseband Pulsar Timing History Caltech Berkeley Processor 1996 10 MHz 2xDLT 7000 Princeton Mk IV 1997 10 MHz 2xDLT 7000 S2TCI (~1997) York University/Melbourne Uni/Swinburne 16 MHz 8xVHS CPSR1 (~1999) Caltech/Swinburne 4xDLT 7000
3
Baseband History COBRA Coherent Baseband Recorder 2001? 150+ Processors CPSR2 (2002) 2x64 MHz x 2bits x 2 pols 30 Xeon dual processors Arecibo Signal Processor (ASP) 03/04? 64 MHz with polyphase filters and 4 bits
4
Selected Achievements Princeton Mk IV MSP timing, ~200 ns timing on 1713+0747 PUMA2?? CPSR1 130 ns timing on PSR J0437-4715 CPSR2 Polarimetry of 27 MSPs Giant Pulses discovered in MSPs Precision timing on 7 MSPs (< 1 us) 0437, 0613, 1600, 1713, 1744, 1909, 1937 Several others near ~1 us
5
Giant Pulses Giant Pulse 2 microseconds wide!
6
Timing 75 nanosecs
7
Stability
8
Profile Precision Must be done with Coherent dedispersion
9
New DFB Limitations 2048 channels/ 512 MHz L-band Terzan 5 190 us Smearing! Still need coherent dedispersion
10
Current Generation IF Samplers + FPGA Bits Polyphas e bits CPU 1 Gb ethernet Gb SwitchCPU
11
Next Generation “APSR” ATNF/Parkes/Swinburne/Recorder 1 GigaByte/sec recorder/processor Much higher timing precision Nanosecond pulse sensitivity Lunar Experiments Giant pulses Pulsar searches Polarimetry Spectroscopy VLBI correlator?
12
APSR IF Samplers + FPGA Bits Polyphas e bits CPUs x16 Gb ethernet x16 Gb Switch 144 ports min CPU x128 1 GHz x 2
13
Specs Limited to 64 MB/s per host Current Gb limit 16 Primaries 64 MB/s 2 bits x 64 MHz x 2 pols 3 GHz 4 bits x 32 MHz x 2 pols L-band 8 bits x 16 MHz x 2 pols Bright Pulsars
14
Primary Machines 3 GB RAM Gb ethernet x 2 500 GB SATA disks 16 of them
15
Secondaries Low-voltage next-gen Pentium 2 GB RAM (min) 2 x 250 GB SATA drives Probably rack-mounted Gb ethernet
16
Switch 144 ports Gb ethernet 10 Gb uplink Probably CISCO
17
Costings Primaries: 48 K Secondaries: 128 K Switch: 12K Cabling: 8K Racks: 15K Total: 211K
18
Required Modes: Mode 1 Raw data x 16 2 bits x 64 Msamples/sec x 2 pols x 16 (agg 1 GHz) 4 bits x 32 Msamples/sec x 2 pols x 16 (agg 512 MHz) 8 bits x 16 Msamples/sec x 2 pols x 16 (agg 256 MHz) Mode 2 Polyphase FB 2 bits x 64 MHz x 2 pols x 16 (agg 1024 MHz) 4 bits x 32 MHz x 2 pols x 16 (agg 512 MHz) 8 bits x 16 MHz x 2 pols x 16 (agg 256 MHz)
19
Required Modes: Mode 3 Polyphase FB - single host 2048 chans x 2/4/8 bits x Npol x 32 us sampling Up to 64 MB/s Mode 4 Polyphase FB - multi-host 16 x PPFB x nbits x nchans x Npol x Nus samples Mode 4 As for 3, but incoherently dedispersed into N channels Mode 6 As for 4, but coherently dedispersed Mode 7 As for 3, but folded for N PSRs simultaneously Mode 8 As for 6, but folded for N PSRs simultaneously
20
Other Wishes: New digital FB for next MB survey 13 DFBs with 300 MHz BW, 2048 channels, 64 us sampling
21
APSR 16 Primaries Switch 128 CPUs 10 Gb To Grangenet Ghz DFB 16?xDFB IFs 13xIFs GHz Apple XRAIDs 16? lines ?
22
Aggregate Power CPUs: 128 x 4GHz x 4flops/cycle = 2 Teraflops Disk: 64 Terabytes (17 hours recording) Pulsar surveys in real time
23
Issues: Heat dissipation 144 x 150 W = 20 KW!! Multiplexing IO to CPUs How can I take 1 GB/sec and spread it 16 ways without losing bits??
24
Upon Completion: Throw out: CPSR2 WBC DFB1 MB correlators Analogue Filters VLBI recorders
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.