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Transient SETITransient SETI
Dan Werthimer Dan Werthimer University of California, BerkeleyUniversity of California, Berkeley
http://seti.berkeley.edu/
University of California, Berkeley SETI University of California, Berkeley SETI ProgramProgram• Graduate Students Graduate Students Chen Chang, Pierre Droz, Aaron Parsons, David PurdyChen Chang, Pierre Droz, Aaron Parsons, David Purdy
• Undergraduate StudentsUndergraduate Students
Daniel Chapman, Henry Chen, Charlie Conroy, Wonsop Sim Daniel Chapman, Henry Chen, Charlie Conroy, Wonsop Sim
• Astronomers, Computer Scientists and Astronomers, Computer Scientists and Engrs.Engrs.
David Anderson, Bob Bankay, Jeff Cobb, Court Cannick, Eric David Anderson, Bob Bankay, Jeff Cobb, Court Cannick, Eric Korpela, Matt Lebofsky, Jeff Mock, Rom Walton, Dan WerthimerKorpela, Matt Lebofsky, Jeff Mock, Rom Walton, Dan Werthimer
Early Transient Early Transient TransmittersTransmitters
NOT FUNDED
NOT FUNDED
Porno in space:
FUNDED!
UC Berkeley SETI UC Berkeley SETI ProgramsPrograms
NameName Time ScaleTime Scale Search TypeSearch Type
SERENDIPSERENDIP secondsseconds radio sky radio sky surveysurvey
SETI@homeSETI@home mS - secondsmS - seconds radio sky radio sky surveysurvey
AstropulseAstropulse nS - mSnS - mS radio sky radio sky surveysurvey
SEVENDIPSEVENDIP nSnS visible visible targettedtargetted
SPOCKSPOCK 1000 seconds1000 seconds visible visible targettedtargetted
DYSONDYSON IR targettedIR targetted
AstroPulseAstroPulse• Arecibo Sky surveyArecibo Sky survey
– Covers decs 0 to 30, each beam 5 timesCovers decs 0 to 30, each beam 5 times
– 1420 MHz, 2.5 MHz bandwidth1420 MHz, 2.5 MHz bandwidth
– 7 years of data recorded so far (70 TB)7 years of data recorded so far (70 TB)
• Good time resolutionGood time resolution– Sensitive to 0.4 µs radio pulses at 21 cmSensitive to 0.4 µs radio pulses at 21 cm
• DM rangeDM range– -1000 to +1000 pc/cm-1000 to +1000 pc/cm33
• SensitivitySensitivity– 1010-18-18 W/m W/m22 peak (Coherent de-dispersion) peak (Coherent de-dispersion)
AstroPulseAstroPulse• Only ~1.5 searches for single pulses on Only ~1.5 searches for single pulses on
µs timescale before µs timescale before (O’Sullivan, Phinney) (O’Sullivan, Phinney)
• Pulsar searches: ms time scales, foldedPulsar searches: ms time scales, folded
• SETI@home: 0.8 ms single pulses.SETI@home: 0.8 ms single pulses.
• Potential astrophysics as well as SETI Potential astrophysics as well as SETI
• evaporating primordial black holes?evaporating primordial black holes?
(Hawking, Rees, Ekers) (Hawking, Rees, Ekers)
– Pulsars, Other astrophysical exotica?Pulsars, Other astrophysical exotica?
Piggyback ALFA Sky SurveyPiggyback ALFA Sky Survey• Improved sensitivity Improved sensitivity
– Tsys, integration timeTsys, integration time
• Uniform sky sampling Uniform sky sampling – galactic plane concentrationgalactic plane concentration
• Multibeam RFI rejectionMultibeam RFI rejection
• Larger BandwidthLarger Bandwidth
Pulsed vs. CWPulsed vs. CW
Concentrating power into short bursts can be more efficient than a “constantly on” transmitter.
Pulsed signals can be easier to see above background noise.
DispersionDispersion
Coherent De-dispersion
-1000 < DM < +1000
Requires lots of Computing!!!
AstroPulse TestingAstroPulse Testing
Sample batch of data run through shows expected noise characteristics, and little else …
… so (hopefully) little RFI contamination for this type of signal.
BOINCBOINC
• Berkeley Open Berkeley Open Infrastructure for Network Infrastructure for Network ComputingComputing
– General-purpose distributed General-purpose distributed computing framework.computing framework.
– Open source.Open source.
– Will make distributed Will make distributed computing accessible to computing accessible to those who need it. (Starting those who need it. (Starting from scratch is hard!)from scratch is hard!)
ProjectsProjects• AstronomyAstronomy
– SETI@home (Berkeley) SETI@home (Berkeley)
– Astropulse (Berkeley)Astropulse (Berkeley)
– Einstein@home: gravitational pulsar search (Caltech,…)Einstein@home: gravitational pulsar search (Caltech,…)
– PlanetQuest (SETI Institute)PlanetQuest (SETI Institute)
– Stardust@home (Berkeley, Univ. Washinton,…)Stardust@home (Berkeley, Univ. Washinton,…)
• Earth scienceEarth science
– Climateprediction.net (Oxford)Climateprediction.net (Oxford)
• Biology/MedicineBiology/Medicine
– Folding@home, Predictor@home (Stanford, Scripts)Folding@home, Predictor@home (Stanford, Scripts)
– FightAIDSathome: virtual drug discoveryFightAIDSathome: virtual drug discovery
• PhysicsPhysics
– LHC@home (Cern)LHC@home (Cern)
• OtherOther
– Web indexing/searchWeb indexing/search
– Internet Resource mapping (UC Berkeley)Internet Resource mapping (UC Berkeley)
5,464,550 participants (in 226 countries)
2,000 per day
2.3 million years computer time
1,200 years per day
4*1021 floating point operations
65 Tera-flops
SETI@home Statistics
TOTAL RATE
Optical SETI Pulse SearchOptical SETI Pulse Search
1961 Charlie Townes Paper 1961 Charlie Townes Paper
largely ingored until 1999largely ingored until 1999
1971 Cyclops report calculates radio >> 1971 Cyclops report calculates radio >> opticaloptical
Today’s lasers can communicate across Today’s lasers can communicate across galaxygalaxy
Optical SETIOptical SETI• Uses Leuschner Uses Leuschner
Observatory (UCB)Observatory (UCB)– Automated 0.8m Automated 0.8m
telescopetelescope
• Targeted SearchTargeted Search– Nearby F,G,K,M starsNearby F,G,K,M stars
– ~10,000 stars ~10,000 stars observed so farobserved so far
– 100 galaxies100 galaxies
OSETI DetectorOSETI Detector• 3-Photomultiplier fast 3-Photomultiplier fast
coincidence detectorcoincidence detector– Sensitive to 1ns pulsesSensitive to 1ns pulses
• Low backgroundLow background– False alarm rate: 1 per 300 False alarm rate: 1 per 300
hours (10hours (10-6-6 Hz) Hz)
– Double false alarm rate: 1 Double false alarm rate: 1 per 600 years!per 600 years!
• Good sensitivityGood sensitivity– 1010-8-8 W/m W/m22 peak peak
– 1010-19-19 W/m W/m22 average average
Transient InstrumentationTransient Instrumentation
Compute Module DiagramCompute Module Diagram
138 bits 300MHz DDR 41.4Gb/s
4GB DDR2 DRAM12.8GB/s (400DDR)
100BTEthernet
5 FPGAs2VP70FF1704
FPGAFabric
MG
T
Memory Controller
IB4X/CX4 20Gbps
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
DR
AM
FPGAFabric
MG
T
Memory Controller
FPGAFabric
MG
T
Memory Controller
FPGAFabric
MG
T
Memory Controller
FPGAFabric
MGT
Memory Controller
IB4X/CX4 40Gbps
IB4X/CX4 40Gbps
IB4X/CX4 40Gbps
IB4X/CX4 40Gbps
19” 48RU Rack Cabin 19” 48RU Rack Cabin CapacityCapacity
• 40 compute nodes in 5 chassis (8U) per 40 compute nodes in 5 chassis (8U) per rackrack
• Up to 16 trillion CMac/s performance per Up to 16 trillion CMac/s performance per rackrack
• 250 Watt AC/DC power supply to each 250 Watt AC/DC power supply to each bladeblade
• 12.5 Kwatt total power consumption12.5 Kwatt total power consumption
• Hardware cost: ~ $1MHardware cost: ~ $1M
Global InterconnectsGlobal Interconnects• Commercial Infiniband Commercial Infiniband
switch from Mellanox, switch from Mellanox, Voltaire, etc.Voltaire, etc.– Packet switched, non-Packet switched, non-
blockingblocking
– 24 ~ 144 ports (4X) per 24 ~ 144 ports (4X) per chassischassis
– Up to 10,000 ports in a Up to 10,000 ports in a systemsystem
– 200~1000 ns switch latency200~1000 ns switch latency
– 400~1200 ns FPGA to FPGA 400~1200 ns FPGA to FPGA latencylatency
– 480Gbps ~ 2.88Tbps full 480Gbps ~ 2.88Tbps full duplex constant cross duplex constant cross section bandwidthsection bandwidth
– <$400 per port<$400 per port
ComputeNode
#N
ComputeNode
#1
Infiniband Crossbar Switch
Ethernet Switch
Unified Digital Processing Unified Digital Processing Architecture Architecture
• Distributed per antenna spectral channel processingDistributed per antenna spectral channel processing
• Multiple reconfigurable backend application processingMultiple reconfigurable backend application processing
• Commercial packet switched interconnectCommercial packet switched interconnect
• Backend data pulling through remote DMA accessBackend data pulling through remote DMA access
PolyphaseFilter
Banks
ChannelReorderBuffer
Infin
iban
d S
wtic
h
XMAC imaging
Spectrometer
Pulsar SearchingB
eam
form
ing
PolyphaseFilter
Banks
ChannelReorderBuffer
An #1
An #N
Infin
iban
d
Sw
tich
Moore’s Law in FPGA Moore’s Law in FPGA worldworldComputational Density Comparison
1000
10000
100000
1000000
10000000
10/28/1995
3/11/1997
7/24/1998
12/6/1999
4/19/2001
9/1/2002 1/14/2004
Release Date
(MO
PS
/MH
z)*l
am
da^
2 Processor Peak
FPGA 32-bit int MAC
FPGA maximum sustained performance
1
10
100
1000
10000
100000
12/1/1996
6/19/1997
1/5/1998
7/24/1998
2/9/1999
8/28/1999
3/15/2000
10/1/2000
4/19/2001
11/5/2001
5/24/2002
Release date
MO
PS
(3
2 b
it M
AC
)
100X More efficient100X More efficientthan micro-processors!than micro-processors!
3X improvement3X improvementper year!per year!
Future SpectrometersFuture Spectrometers2015 4 THz 400 beams
10 GHz each2020 128 THz 12,800 beams
2025 4000 THz 40,000 beams
2030 128,000 THz 1M beams
Why you might not want Why you might not want to collaborate with us on to collaborate with us on Transient Observations Transient Observations
Seti Haiku
Searching for lifeSearching for lifeAnswers are revealedAnswers are revealedAbout ourselvesAbout ourselves
Paula Cook, Duke UniversityPaula Cook, Duke University
One million earthlingsOne million earthlingsBounded by optimismBounded by optimismLeave their PC’s onLeave their PC’s on
Dan SeidnerDan Seidner
The SETI@home ClientThe SETI@home Client
TripletsTriplets
• Three evenly Three evenly spaced spikes spaced spikes above 7.75X the above 7.75X the mean power. mean power. (5.3X10(5.3X10-25-25 W/m W/m22))
PulsesPulses
• Modified Fast Modified Fast folding algorithm folding algorithm w/ dynamic w/ dynamic thresholdthreshold
• Logarithmically Logarithmically spaced periods spaced periods from 3ms to 35sfrom 3ms to 35s
• Sensitivity as low Sensitivity as low as 10as 10-26-26 J/m J/m22