Busan APAN eScience: Minh, Song, & Kim 1
Y. C. Minh, M.-G. Song, and H.-G. KimKorea Astronomy Observatory
Korean VLBI Network (KVN)
and e-VLBI
Contents
Project Summary Special System Characteristics
Science TargetsTime Table
System ConfigurationSite Construction: Yonsei, Ulsan, Tamna
e-KVN
Busan APAN eScience: Minh, Song, & Kim 2
Project Summary
For the VLBI study of astronomy, geodesy, and earth science:
• KVN Observatories: Radio Telescopes of 20m-diameter
VLBI Facilities at Seoul, Ulsan, and Jeju
• Receiving Frequencies: 22, 43, 100, 150 GHz 2/8 GHz (for geodesy)
• VLBI System: DAS, Recorder, Correlator
• Project Period: 2001. 1. - 2007. 12. (7 년 )
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Special System Characteristics
Optimized to mm-VLBI:
• High-precision antennas: - High surface accuracy at 100-150 GHz - High slew speed
• Multi-channel Frontend Receivers: - Low noise cryogenic HEMT receivers
- Multi-channel selections: 22, 43, 100, (150) GHz
• Flexible and High-speed DAS: - Selectable 4 IF streams of wide bandwidth - High sampling rate of 2 Gsps, 4 bits/sample
• Hard Disk-based Recorder and e-VLBI Performance
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mm-VLBI
• Insterstellar Maser study: - SiO: Simultaneous 43, 86, (129) GHz Observations
- H2O, CH3OH maser lines
• AGN Study: - Surveys: Spectral indices at mm-wavelengths,.. - Gamma-ray bursts, X-ray variables,..
• Astrochemistry: - Absorption lines toward compact cores - Interstellar molecule studies at mm-wavelengths
• Gravitational Lensing - Microlensing,..
Science Targets: Astronomical Key ProjectsMira variable (Pulsating star)
Diamond & Kemball
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Science Targets
Geodesic Targets: • Reference Frames: ICRF, ITRF, CORE, ..
• Tectonic Motions of Korea: Fault plans, Jeju island, ..
• Earth Rotation, ..
Astronomical Targets:
From Cosmology to Solar System:• AGN, Quasar, Radio Galaxies, Jets, Gravitational Lens ,..
• Maser Lines: Star-forming regions, Stellar Envelopes ...
• Interstellar Molecules, Astrochemistry ...
KVN Resolution: - ~0.001 arc-second at 100 GHz
- 2mm at 500 km distance
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KVN Construction Time Table
Site Construction
Antenna Installation
Receiver Development
2002
Ⅳ Ⅰ
2007
Ⅱ Ⅲ
Japan-Korea VLBIExperiments
CorrelatorDevelopment
VLBI RecorderDevelopment
DASDevelopment
ⅣⅢⅡⅠⅣⅢⅡⅠⅣⅢⅡⅠⅣⅢⅡⅠⅣⅢⅡⅠⅣⅢⅡⅠ
20062005200420032001
Site Selection SiteDesign
Civil EngineeringWorks
BuildingConstruction
KVN ResearchCenter Const.
Specifications Contract Foundation Installation Calibration
Design Preparation22/42GHz
Rx Manufacturing2/8GHz
Rx Manufacturing Test
Design Manufacturing Software Development
Mk5 Development Manufacturing Installation
Design Manufacturing
KVN ExperimentJ-K 43GHz86J-K
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Recorder
DAS
Recorder
FIR, Formatter
H-Maser Clock
Frontend Rxs
System Configuration
IF Selector, BBC
Sampler
RecorderRecorder
KVN
Center
• System/Observation Remote Control
• Real-time & e-VLBI Operation/Data Synthesis
KVN
Correlator
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KVN Antennas• Slew Velocity: 3 o/sec (in AZ, EL)
• Operating Range: AZ: +270 o ~ -270 o EL: 0 ~ 90 o
• Tolerable Wind Speed: Precision Observation: up to 10 m/s Maximum Survival Velocity: 60, 90 m/s
• Type: AZ/EL, Cassegrain focus
• Diameter: 20m
• Dish: Aluminum
• Total Surface Tolerance: < 150 microm
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Rx 2 GHz 8 GHz 22 GHz 43 GHz 100 GHz 150 GHzFreq. Range 2.2~2.8 GHz 8~9 GHz 21.5~23.5GHz 42~44 GHz 85~115 GHz 120~150GHz
Rx Noise < 25 K < 25 K < 30 K < 50 K < 50 K --1st IF / BW 2.5G/600MHz 8.5G/1GHz 8.5G/2GHz 8.5G/2GHz 8.5G/2GHz 8.5G/2GHzIF Power -20 dBm -20 dBm -20 dBm -20 dBm -20 dBm -20 dBm
Polarization LCP/RCP LCP/RCP LCP/RCP LCP/RCP LCP/RCP LCP/RCP
Front-end Receivers
Low-Noise Cryogenic HEMT
Receivers
- 2/8 GHz: Geodesy
- 22, 43, 100, 150 GHz: Astronomy
- Multi-channel receivers:
mm-VLBI: Phase correction
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DAS (VLBI Data Acquisition System)
IF Inputs: Simultaneous Selection of up to 4 Ifs, Center Frequency: 3 GHz
Bandwidth: 2 GHz
High-speed Samplers: 2 Gsps, 4 bits per sample
Digital Filters: 16 independent channels, 8/16/32 MHz BW
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KVN Recorder
Mk 5 Prototype (Mk5p)
Hard-Disk Type VLBI Recorder: Mk 5
• MIT Haystack Observatory’s Mk5 Project:
Development Consortium (2001. 10.-2003. 10.): MIT, NASA, NRAO, JIVE, BKG, MPI, KVN
• Specifications: 16 hard discs
maximum recording rate: 1 Gbps (expandable)
Standard PC and IDE hard discs
VSI Interface
• KVN Production Plan of Mk 5 (2003~)
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KVN Site Construction
KVN Observatory Locations :
- Seoul: Yonsei University - Ulsan: University of Ulsan - Jejudo: Tamna University
“KVN-Expanded”: a total of 6 antennas
KVN Data Center and Research Center : - Seoul: Yonsei University
UV coverage and synthesized beam shape of
the KVN+TRAO sites (for the Dec=40o source)
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KVN Yonsei Observatory
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KVN Ulsan Observatory
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KVN Tamna Observatory
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KVN: National Facility for VLBI (Very Long Baseline Interferometry)
Data syntheses using the data from remote sites: at present, from
4 sites in Korea, and possibly from foreign countries (e.g. Japan, Europe,
USA, etc.)
To send the observed radio data: it will be very efficient, if using Information Infrastructures, instead of using postal mail of tapes and/or hard-disks.
Data Recording rate: 1 Gbps (> 2 Gbps)
Real-time/e-VLBI Operation: > 1 Gbps
Expected total amount of data to be sent: ~ a few Tbyte/day
KOREN:
e-KVN
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Status of KOREN Korea Advanced Research Network
Special Features Service for next generation Internet research environment (1999 ~), no
commercial service
Service of latest internet technologies (IP Multicast, IPv6, etc.)
Small amount of annual fees, for research purposes
Data transfer rate: 155Mbps ~ 1Gbps (Local), 2.5 ~ 40Gbps (Backbone)
Equipment: IPv4, IPv6, IP Multicast, IP QoS, WDM, ATM Switches, Routers,
Servers
Plan All over the country: > 2.5 Gbps
Data speed between Korea-USA: 155 Mbps (2003. 7.)
Data speed between Korea-EU: to 45 Mbps (15 Mbps at present)
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Seoul
KOREN
Daejon
Daegu
BusanGSR
GSR
GSR
GSR
USA
6 M
10 M
45 M
Japan
1 G
ATM Switch
155Mbps
2.5Gbps
Router
LEGEND
DWDM
40 Gbps
Gigabit Switch
> 2.5Gbps(plan)
TAP
GSR
GSR
Singapore
Europe
Suwon
Gwangju
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StarTAP
10G
CA*net 3
6M
SingAREN
Singapore
Canada
USA
622M×2
WIDE, JGN
Japan
Tokyo-XP
Seoul
Daejon
Gwangju
Busan
Daegu
8M
Suwon
TEN-155
10MNIO
TEIN
TransPAC
45M
vBNS, Abilene
APII Test-bed (Asia Pacific Information Infra.)
TEIN(Trans Eurasia Information Network)
1G
China
Malaysia
Europe KOREN
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e-KVN Configuration
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KVN: VLBI for Astronomy, Geodesy, and Earth Science
- National Project
KVN Data Speed: 1 Gbps (2-4 Gbps at 2007)
Expected Use: ~a few Tbyte/day
Time Schedule for e-VLBI:
- e-VLBI experiment between Japan-Korea: 2004 ~
- e-KVN: 2006 ~
e-KVN:
- Radio Telescope Remote Control
- VLBI Observing Program Execution
- Real-time VLBI Operation: Interferometric fringe test, Real-time image syntheses
- Domestic e-VLBI (IPoDWDM ?): Observed Radio Data Transfer, Quasi-real-time Data Synthesis
- International e-VLBI Projects
e-KVN Summary