Stelio Montebugnoli IRA -INAF- Bologna –Italy-
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Transcript of Stelio Montebugnoli IRA -INAF- Bologna –Italy-
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
Stelio Montebugnoli IRA -INAF- Bologna –Italy-
SKADS 4th -Lisbon- Oct 2-3, 2008
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6DS-6
110
mt
E/W
N/S
24
mt4 receivers
F=408 MHz @ 16 MHz
BEST-1: 170 sqm 4 Rx BEST-2 : 1400 sqm 32 RxBEST-3: 3200 sqm 60 Rx (14 cylinders +1 E/w 24 mt line) equivalent to a 64 mt diameter dish
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
(More details are reported in the J. Monari talk)
DS-6: Basic architecture & related blocksDS-6: Basic architecture & related blocks
optical fiber
F.E. Developed - Single end front end- Differential front end- Balanced front end
Main requirements:- Low cost- Low noise- Reliable- High dynamic range
IFA/D
&Data Proc.LO
distributor LO
OP.Rx
OP.Tx
F.E.
Synth.
Sync
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
Reliabilty prediction exercise for the front end
The analysis has been implemented by means of MIL-HDBK-217H reliability database
Hypothesis:• Reliability Block Diagram: series configuration• 100% Duty cycle• Operating Temperature: 40°C• Operating environment: MilStd Ground MobileMilStd Ground Mobile (Front-end) and MilStd Ground Fixed UncontrolledMilStd Ground Fixed Uncontrolled (Downconversion)
Reliability Data (MTBF) Front-end: 127365 hours 14.5 Years
RELIABILITY PREDICTIONRELIABILITY PREDICTION
By the evaluation of MTBF (Mean Time Between Failures) variations while stillBy the evaluation of MTBF (Mean Time Between Failures) variations while stillin the project design phase, it is possible to increase the system reliability.in the project design phase, it is possible to increase the system reliability.
Florence College of Engineering
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
OpticalTx
OpticalRx
DS-6: Basic architecture & related blocksDS-6: Basic architecture & related blocks
optical fiberIF
A/D &
Data Proc.LO distributor LO
OP.Rx
OP.Tx
F.E.
Synth.
Sync
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
(More details are reported in the F. Perini talk)
Collaboration with ANDREW WIRELESS SYSTEMS and MITEQ on analogue optical links will last till the end of SKADS
• IRA is collaborating with :AWS on the test of a 4.5 GHZ Tx, equipped with a cooled
Laser. MITEQ to optimize a standard commercial products to satisfy
the requirements. A plan to design an ad hoc low cost optical link is considered as well.
… VCSEL represents the only way to reduce costs of the optical link. IRA plans for a prototype at the end of SKADS but it is not clear the role that ANDREW and MITEQ will play in this task.
DS-6: Basic architecture & related blocksDS-6: Basic architecture & related blocks
optical fiberIF
A/D &
Data Proc.LO distributor LO
OP.Rx
OP.Tx
F.E.
Synth.
Sync
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
Xmas tree OLdistribution
Div x 8
IFA/D
&Data Proc.LO
distributor LO
OP.Rx
OP.Tx
F.E.
Synth.
optical fiber
Sync
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
IFA/D
&Data Proc.LO
distributor LO
OP.Rx
OP.Tx
F.E.
Synth.
optical fiber
Sync
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
A/Filt.
A/D &
Data Proc.
OP.Rx
OP.Tx
F.E.
Synth.
optical fiber
Sync
RF Direct Digitization …potentially possible with the “Casper” system…BEST works at 408 MHz and the A/D can sample at more the 1 GS/s.
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
Input ofOptical fibre
IF
IFA/D
&Data Proc.LO
distributor LO
OP.Rx
OP.Tx
F.E.
Synth.
optical fiber
Sync
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
IFA/D
&Data Proc.LO
distributor LO
OP.Rx
OP.Tx
F.E.
.
optical fiber
Sync
Sync x 32 for A/Ds
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
Low Noise balanced Amplifier
IF Amplifier
Architecture and technology for immediate application onthe BEST - x demonstrator construction (T0+10mo).
Optical Fiber
To A/D & Signal Proc.
From Sensor
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
IFA/D
&Data Proc.LO
distributor LO
OP.Rx
OP.Tx
F.E.
.
optical fiber
Sync
For the A/Ds and post processing blocks, the Berkeley-CASPER Boards have been used….
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
Wide band A/D converter: dual 8 bits @ 1 GS/Sec converter (4 A/D for each IBOB packetizer board
Wide band A/D
FPGA
CASPER system :A/D+ IBOBs + Bee2 Our collaboration is starting with South Africa and Berkeley
A/D+ IBOB
A/D and data Processing
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
One Bee2 board can deliver 500 GOps/sec with a 400 W power supply.
• 6.7 MOps /€•1.25 GOps/W
A/D and data Processing
Xilinx Virtex 2 Pro 70(100 as well)
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
A/D and data Processing
A 32 receivers FX correlator (2048 ch)has been programmedin 1 week time in the frame of a colalboration starting from South Africa (Alan Langman, Jason Manley), IRA and Berkeley (D. Werthimer, Aaron Parsons).
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
∑FFTZ-n
FFTZ-n
FFTZ-n
∑
∑
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
Basic FX Correlator block diagram
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
Basic Modular FX Correlatorblock diagram
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
FX correlator with Bee-2FX correlator with Bee-2
- Complex multiply allows for fine delay control and per channel digital gain control- White coloured blocks not yet implemented
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
1-2 interferometer
CAS. A, 1 h of data
Rx1, Rx 2 baseline (outermost receivers). The fringes are clearly visible. However, the RFI are quite big.
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
1-2 interferometer
CAS. A, 1 h of data
…… with the RFI flagged. The fringes are now clean.
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
CAS. A, 1 h of data
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
CAS.A with strong RFIs (Tv station in the lower part of the band)
CAS. A, 1 h of data
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
CAS. A, 1 h of data
CAS.A with strong RFIs (the Tv station in the lower part of the band are mitigated)
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: T4 Phased array on concentrators T4 Phased array on concentrators
Focusing the task with J.G. B.de Vaate and Laurens Bakker
It could be feasible to install a tile on the focal line… …..but after an electromagnetic analysis
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
• A zoom shows the strong source in the center and the image artifacts. The deconvolution worked very well. Most of the source has been phased up into a single pixel at 50deg 48min 53.6s (CAS)
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks
S.MontebugnoliBEST4th SKADS Workshop, Lisbon, 2-3 October 2008
DS-6: DS-6: Basic architecture & related blocksBasic architecture & related blocks