Name of Speaker 1

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DS-6
IRA INAF Bologna (I)
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DS-6

• DS-6 is aimed to the construction of 3
  demonstrators, different in size, based on a
  large existing platform equipped with cylindrical
  concentrators (Northern Cross array located in
  Medicina Bologna I-)

BEST-1?176 sqm
BEST-2?1410 sqm
BEST-3?7464 sqm
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Achieved milestones and deliverables T1

• Gantt for DS-6 T1 Design of subsystems

Deliverables 1- Receiver LNAs, Analog Optical
link, IF stages. 2- Wideband A/D converter 125
MHz _at_ 14 bit (I Q) DDC . 3- Reliability
prediction.
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Achieved milestones and deliverables T2

• Gantt for DS-6 T2 Development and
  demonstration of the BEST-1,-2,-3 large SKA
  platform as part of the NC (408 MHz)

.
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Achieved milestones and deliverables T2
(Connection with DS-4 T3)

• Gantt for DS-6 T2 Development and
  demonstration of the BEST-1,-2,-3 large SKA
  platform as part of the NC (408 MHz

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Achieved milestones and deliverables T2
RFI mitigat.-gtMVDR (BEST-1)
DOA RFI
(Connection with DS-4 T3

• N.sensors 4
• Sensor 16 ?/2 dipoles
• Sensor spacing8?
• Samples used for R 200
• Primary beam 2o
• DOA RFI 12o, -23o, 30o

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Achieved milestones and deliverables T2
RFIs mitigat.-gtMSC (BEST-1) (Connection with DS-4
T3)
Preliminary test
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Achieved milestones and deliverables T2

• RFIs Mitigation via Polyphase filter bank
  (BEST-1) (Connection with DS-4 T3)

Channel Threshold level
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Achieved milestones and deliverables T3
- Data simulation -Simulation of BEST-X data
outputs -Software validation through comparison
with real BEST-X data
Milestone not reached yet (in progress)
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Achieved milestones and deliverables T3
Tsys computed
The Tb distribution has been computed, according
with the G.Cortes paper (Antenna Noise
Temperature Calculation), with an ad hoc written
Matlab code
BEST-1 Pn comp. GRASP model
Result (integral was resolved with an ad hoc
written fortran code) Tant 35 K Then the
computed Tsys is Tsys 86.3 K
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Achieved milestones and deliverables T3
Tsys measured
where ½ single polarisation ? antenna
efficiency (0.71) Ag BEST-1 antenna total
geometrical (area 176 m2) k Boltzman constant
System Equivalent Flux obtained from Cas A,
Virgo, Taurus and Cygnus-A observation
86.3 K
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Potential of FPAs for cylinders DS-6 T4

• This is a T032 task but some preliminary
  considerations could be useful for other tasks
  (4x4 antennas subset of EMBRACE installed on the
  focal line of one cilyndrical concentrator)

• It could be useful to test on the field the
  deliverables from
• DS-4 T1
• DS-4 T3
• DS-4 T4
• DS-4 T6

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Next milestone, next deliverable (18 months)

• T1 -Milestone - End of the design of BEST-2
• - Start of the design of BEST-3
• -Deliverables - Analogue digital opt. links
• T2 -Milestone - End of construction of
  BEST-2
• - Start of construction of BEST-3
• -Deliverables- L.O. Sync distrib. Scheme
• - Wide Band high res. A/D - Softw.
  Beamform. Algorithms(Best-2)
• - Adapt. Beamf./RFI mit. Algorithms

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Next milestone, next deliverable (18 months)

• T3 -Milestone Test of BEST-1 2 data
  output simulation software.
• Validation through
• comparison with real BEST-X output
  data
• - Deliverables Data output simulation
  software for BEST-3 and other

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Technical progress
Balanced Front End under test .
S11? -37.5 dB S22? -27.0 dB S21? 24.5 dB IP3?
34.5 dB NF? 0.45 dB
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Technical progress
IRA-INAF / Andrew analog Link (0.1-2.5 GHz) IRA-INAF / Andrew analog Link (0.1-2.5 GHz)
Gain gt 3.5 dB
Input Return loss gt 17 dB
Output Return loss gt 15 dB
Input IP3 gt31 dB
Noise figure 37 dB
The Challenge to be faced is the cost reduction..
IRA-INAF / Andrew analog Link
Link (not optimised) in the 300-600MHz band Link (not optimised) in the 300-600MHz band
Gainmin -23.7dB
Gainmax -22.1dB
Input Return Loss gt9.5dB
Output Return loss gt24.2dB
Input IP3 gt30dBm
Noise Figure lt31.25dB
IRA-INAF analog Link
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Technical progress

• Polyphase filter bank (FX Correlator)

• 2x A/D_at_14 bit (Analog
• Device 6645) (I/Q)
• - 105 MSPS.

• Xilinx Virtex 2, series 3000
• ?1616 bit word at
• up to 4K channels
• 88 bit word at up to 8K channels

PCI Bridge
100 MHz I/Q prototype digitizer Poliphase
Filter Bank (PCI)
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Technical progress
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Reliability Prediction BEST-1(DIT Florence
University)
This analysis has been performed using the
following tools and hypothesis

• MIL-HDBK-217-FN2 data base
• series reliability model 
• 100 duty cycle
• operating temperature 30C
• environments
• GM (Ground Mobile) for antenna equipment
• GF (Ground Fixed Uncontrolled) for cabin
  equipment
• GB (Ground Benign Controlled) for processing
  room equipment

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BEST-1 Receiver Chain case 1

Reflector 8
Reflector 1
Focal line
2
3
4
5
6
7
Base band and A/D conversion
GM
D
D
C
C
4
4
4
4
4
4
B
B
A
A
Digital sampling clock and local oscillator
signals
700m Optical Fibre (digital)
Cabin
Coaxial cable (70m)
GF
Power supply
Data processing
8 reflectors for each cabin 4 x 8 32 receivers
for each cabin
CLK
PPS
GB
Processing room
LO
408 MHz
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BEST-1Receiver Chain case 2
Reflector 8
Reflector 1
Focal line
2
3
4
5
6
7
Base band and A/D conversion
GM
D
D
C
C
4
4
4
4
4
4
B
B
A
A
700m Optical Fibre (analogue)
Cabin
Optical fibres (70m)
GF
Power supply
Data processing
LO
408 MHz
8 reflectors for each cabin 4 x 8 32 receivers
for each cabin
Processing room
CLK
PPS
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Reliability PredictionBEST-1
Reliability, Availability and Maintainability
(RAM) analysis is an important aid in the design
and management of complex systems.
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UPDATED DS-6Time Table
In generale
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Conclusion

• As a general rule, the DS-6 milestones and
  deliverables are achieved.
• The plan is to be ready with BEST-2 (maturity of
  the technology, costs first astronomical
  observation) for the mid term review.

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