KVN

Duk-Gyoo Roh
Se-jin Oh, Jae-Hwam Yeom, Chungsik Oh, Youngjoo Yun,Jinseung Jung, Dong-Kyu Jung, A. Miyazaki,
M. Kim, H. Kim, T. Jung, S. Lee, D. Byun, Jongsoo Kim,
T. Oyama, K. Shibata, N. Kawaguchi, H. Kobayashi,
S. Sawada-Sato, N. Matsumoto, Y. Kan-ya, T. Kurayama-- Correlator team of KASI/NAOJ --2013 VERA-UM, NAOJ Mitaka, 2-3, Oct. 2013

22GHz43GHz
86GHz
110GHzSimultaneous Multi-Frequency Obs. Phase Compensation, mm-VLBI

Dual beam – Phase Compensation,
Differential VLBIKaVAKJJVC Framework

Mark5B

Raw
VLBI
Data
Buffer(RVDB)VERA2000

OCTADISKVLBICorrelation
Subsystem(VCS)

Optical Fiber

Correlator Control & Operation S/W
Joint Development started from 2005. 7. 7.

Correlated
VLBI
Data
Buffer(CVDB)

KJCC

Organization of KJCC
Joint Operation started from 2011. 7. 20.

Memorandum of Agreementfor Korea-Japan Correlation Center Joint Operation
President of KASI, Director General of NAOJ

Executive Board
Director of Radio Astronomy Division(KASI)
Director of Mizusawa VLBI Observatory(NAOJ)Manager of RA Project Center(KASI)
Chair of East Asian VLBI Network(international)
Correlator Manager(KASI)
System Engineer(KASI, NAOJ)
System Scientist(KASI, NAOJ)

Operation Group (KASI)

Operation Group (NAOJ)

Deajeon Correlator

Joint Development & Joint Operation
by KASI & NAOJ

Highest Data Rate in the world (1GB/sec•Station)x # of Stations (upto 16 Stations)x Finest Spectral Resolutions in the world(8,192 Channels)

 Heart of East Asian VLBI Network !

Debug & Regulation
Overcome the Differences between
KVN and VERA Different recorder/playback equipment Different sub-stream assignment Different observation log format
Initial bugs in firmware
 Delay tracking
 Fringe rotation (phase calculation)
 Data pollution at FFT segment border Underflow/overflow at FFT butterfly processDebug & Regulation
Post-correlation Software CODAgen, FITSgen, GFS
 Complex algorithm for heterogeneous array Speed up (8H KaVA observation, 16x16MHz)• CODAgen: 3~4H
• FITSgen: ~1H

Now, KJCC can serve for usual 1Gbps(16MHz x 16 Channel) observation.
At Sep 24, there was the first EAVN
fringe test observation.

Operation Modes
Recording Mode

Data RateOper. Speed

Service Status

16MHz x 16Chan

1Gbps

double32MHz x 8Chan

1Gbps

double64MHz x 4Chan

1Gbps

double128MHz x 2Chan

1Gbps

double2014~

256MHz x 1Chan

1Gbps

double2014~

512MHz x 1Chan

2Gbps

normal2014~

512MHz x 2Chan

4Gbps

normal512MHz x 3Chan

6Gbps

normal512MHz x 4Chan

8Gbps

normal2013~

Correlation Status
Exp.

ObjectCorrelation

StatusR11027B

KVN+VERA
Evaluation for KJCC

Finished

In Analyzing

K12098CKVN 4channel
simultaneous obs

Finished

In Analyzing

R11025A

KVN+VERA
22GHz

Finished

In Analyzing

R11026A

KVN+VERA
43GHz

Finished

In Analyzing

R12280A

KVN+VERA
43GHz survey

Finished

In Analyzing

R11088B
R11089B
R11090B
R11091B
R11093B
R11095B

KVN+VERASgrA* campaign

Finished

In Analyzing

R11094A,B

22/43 GHz KVN+VERA

Finished

In Analyzing

R13082B
R13083B
R13084B
R13085B
R13086B
R13102A

KVN+VERASgrA* campaign

Waiting forcorrelation

Data copy finished

OthersWebhttp://kjcc.kasi.re.kr/ is initiated.

Recent Results : 3C454.3

Peak = 20Jy/beam

KaVA 22GHz Snap shot (10min)

VLVA 15GHz Snap shot (30min)

Peak = 20Jy/beamRecent Results : Sgr B2 N

KaVA, H2O Maser (22GHz)

Near FutureRVDB upgrade (~2013)
 OCTADDB  OCTADISK (3 ea)
 New OCTADISK2 (2 ea)
Setup other observation modes (~2013)
 128MHz x 2 Channels (1Gbps)
 256MHz x 1 Channel (1Gbps)
 512MHz x 1 Channel (2Gbps)
 Dual polarization (~2014)
New recorder for 4~8Gbps (2014~)
 Mark6 / OCTADISK2

Summary
Joint development of Daejeon correlator
Joint operation of KJCC
KJCC is now in service for usual 1Gbps(16MHz x 16 Channel) observation.

Specification (1)Items

Specifications

Number of Antennas

16

Number of Inputs / Antenna- Input Interface- Maximum Data Rates

4- 2Gbps VSI-H (32parallels, 64 MHz clk)
- Total of 8,192 Mbps

Digitization for Each Inputs- Number of Bits
- Quantization Levels- Sampling Rates- Input Bandwidth- Sub-stream Specification- 2 bits/sample- 4 levels- 1,024 Msamples/sec- 512 MHz- Logically Associated Sub-streams

Maximum Delay Compensation(Largest Baseline Length)±36,000 km

Maximum Fringe Tracking(Fastest Phase Drift Cancellation)

1,075 kHzArchitecture

FX type, with FPGA and DSP chips

Specification (2)Items

Specifications

FFT Processing- Freq. Resolution- Size of FFT points- Word length in FFT- Scaling- Re-quantization- 0.05km/sec @ 22GHz- 256k/128k/64k/32k/16k/8k Adjustable- 20+20 bits fixed point for real & imaginary- Yes- 16+16 bits fixed point for real & imaginary△W Correction

Yes

Correlations- Number of Correlation Outputs/Input - Max. 120 Cross- and 16 Auto-correlations- Total Number of Correlation Outputs - Max. 480 Cross- and 64 Auto-correlations- Polarization Mode
- RR or LL ; Full Operation for 16 antennas
RR and LL ; Full Operation for 16 antennas
RR, RL, LR and LL : Full Op. for 8 antennas- Data compression(Binning)- Yes, 8,192 channels / correlation output- Word length- 32+32 bits Fixed Point for R & I- min. max Integration Time
- 25.6msec ~ 10.24sec
Data Output to Archive (Max.)

1.4 GBytes/sec

Subarray Operation

2 cases (12 + 4, 8 + 8)

Recorder/Playback Systems
 Mark5B for KVN, CVN, VSOP-2
 VERA2000 for VERA Playback only version of DIR-2000
 OCTAVIA for some JVN sites (Yamaguchi, …)
 Optical Fiber for some on-line sites (1~2Gbps, upto 8Gbps for near future) OCTAVIA/OCTADISK Modified from RVDB Currently 4Gbps, but
8Gbps coming soon.
 New high speed recorderas Next generation of DIR2000, Mark5B
 And also the replacementof RVDB and VERA2000/
Mark5B playback at KJCC