IRASEB

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ARGOS
Astronomical Receiver Gathers Outer Space
(Tyler Brulée)
Double - Heterodyne - FFT - Radio -
Spectrometer RAPP ETH Zürich
Minikolloquium June 11th 2002 Michael Arnold /
Christian Monstein
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Directory

• Specifications (required / measured)
• Instrument comparison
• Open day application 15.06.2002
• Usage sites
• Focal plane unit
• Double heterodyne receiver
• Frequency diagram
• Backend hardware
• Backend software
• Backend realtime aspects
• Backend dataflow
• First results
• Team members
• Development time, costs
• Summary
• ARGOS related URLs

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Specifications

• Parameter Required Measured
• Frequency range 1415 25 MHz 1415 125 MHz
• Bandwidth 50 MHz 250 MHz
• Polarization 1 linear vertical
• Spectra/sec 100 10...15
• Integration (TD, FD) must in progress
• Channels or bins 32 up to 50000 tested
• Offseterror vs temp. nil
• Offseterror vs ac-power nil
• Gainerror vs temp. nil
• Gainerror vs ac-power nil
• Frequency error nil
• Timing error
• Power consumption nil 191W (RX only)
• Sensitivity
• System temp.
• Dynamic broadband nil 40 dB
• Dynamic FFT 24 dB 50 dB
• Liftime 5 year TBD

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Instrument comparison
Parameter ARGOS PHOENIX-2 CALLISTO Receivertype
FFT Frequency agile Frequency agile Frequency
range 1290-1570 MHz 100-4000 MHz 47-862
MHz Obs.-bandwidth 250 MHz 3900 MHz 815
MHz Resolution (FD) ? 250 MHz i 1, 3, 10
MHz 110 KHz (65 KHz) Resolution (TD) 66
msec 500 µs...1sec i 2 msec...10 sec
i Polarization linear (vertical) L, R, I,
V linear Sampletime/pixel 2 nsec 0.5 msec 2
msec (TBD) Channels 1...? ii 1...2000 1...125
00 System temp. 250/530 K iii TBD iii TBD
iii RMS noise 300/800 Jansky TBD iii TBD
iii Dynamic range 50 dB 40 dB 40 dB
i depending on number of channels ii not yet
checked tested until 50'000 iii with/without
calibration unit
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Open day application 15.06.2002

• Possible sources
• Solar radio noise between 11,70 GHz and 12,75
  GHz
• Satellite signals (downlinks)
• Methanol CH3OH _at_ 12,178 GHz doppler shift
• Cherenkow radiation from moon due to impact of
  TeV cosmic particles

SAT-receiver power supply LNC
Receiver 1415 MHz125 MHz
Impedance matching 75/50 ? DC-decoupling
IF1578 MHz
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Usage sites
5m antenna Bleien 300 MHz - 3 GHz 80 cm-SAT 10
GHz - 12 GHz
5m antenna Zürich 1 GHz-2.6 GHz (system tests
only)
7m antenna Bleien 100 MHz - 4 GHz
Option Gorner Grat with 3m Cassegrain 210 - 820
GHz
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Focal plane unit
Ta/Cali
Noise Source 35 dB ENR
28V
-3 dB
J2.1PD1
Input from antenna feed
PIN- switch 1
PIN- switch 2
To/Texc
J2.0
J1.1PD3
J1.2PD4
5V/-12V
J1.0
J2.2PD2
Termination 50? _at_ To300K???
Preamplifier, 1-4 GHz NF 0.9dB, G 35 dB
15V/0,3A
Output to receiver
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Double heterodyne receiver
Radio - Telescope 1290 - 1540 MHz
LSB-bandpassfilter 8,585GHz 125MHz
1. IF- amplifier
equalizer- amplifier
2. IF- amplifier
1. mixer
2. mixer
-3dB
-3dB
isolator
isolator
X
X
26dB
15dB
41dB
Coaxial cable 60m -9dB ...-35dB
isolator
isolator
local oscillator-1 10,000GHz 13dBm
local oscillator-2 8,710GHz 13dBm
Power- divider
IF2IF1-Flo IF1Fsy-Frf FrfFsy-IF2-Flo IF2Fsy-Fl
o-Frf
100µA Video
Reference clock 10MHz 6dBm 3dBm
Logarithmic detector 25mV/dB
-1.7dB
Power- divider
analog-digital- converter 8bit 500Ms/sec
PC
Lowpassfilter DC-250MHz
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Frequency diagram
1. Localoscillator LO1 10,000 GHz
Upper sideband USB will not be used
Power
Selection of lower sideband LSB by bandpassfilter
1. mixer stage
F1 LO1 Frf 8,585 GHz 125 MHz
Frequency
Fh1,540 GHz
Frf 1,415 GHz
Fl1,290 GHz
F1h8,710GHz
F1z8,585GHz
F1l8,460GHz
Power
2. mixer stage
2. Localoscillator LO2 8,710 GHz
Selection with lowpassfilter
F2 F1 - LO2 125 MHz 125 MHz
Frequency
F2h 250 MHz
F2l 0.0 GHz dc
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Backend hardware
PC HardwarePentium III 800 MHz (Win98) 384
MByte RAM 40 GByte HD Acqiris Digitizer 500
Msamples/sec 2 Msamples on-board memory 8bit
Resolution 50? input impedance LabView Driver
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Backend software
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Backend realtime aspects

• 50000 lines/spectrum (??5KHz)
• Spectral integration down to 500 lines/spectrum
• Sampletime 2ns (500MHz)
• 100?s per data array (one line of spectrum)
• Fastest Win98 timeslice 1ms ? needs fast
  integration
• Bottle neck disc I/O and integration process in
  time

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Backend dataflow
Fileserver
ftp via php
ARGOS Receiver
hercules.ethz.ch
/ftp/pub/hedc/fs/data1/rag/observations/argos
Webserver
Argos Controller
ftp.php
Overview
pisces.ethz.ch
plutos.ethz.ch
/argos/
D/data/.raw
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First results
Simulation of RADAR-pulses (top) and a small
bandwidth, drifting signal to check cross-modulati
on sensitivity of the preamplifier in the focal
plane unit. Here, rf-power is to high thus
ghosts apear parallel to signal.
Testband Frequencyrange max Power ERMES-pager 16
8-172 MHz dBm Citizenband 900-1350 MHz dBm RADAR 1300-1350 MHz D/GSM 1710-1855 MHz 5µW (16mV _at_ 50?)
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Sun-transit seen with ARGOS PHOENIX-2
PHOENIX-2
ARGOS
No background subtraction applied...
FFT-spectrometer BWspacing500KHz
Frequency agile spectrometer BW10MHz,
spacing30MHz
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Team members
Defending NF-budget requirements Arnold
Benz Mechanical design manufacturing Frieder
Aebersold Software design, integration
test Michael Arnold Postprocessing Peter
Messmer Manufacturing of focal plane
unit Andreas James Manufacturing
ARGOS-receiver Roland Moser Manufacturing
FOPA-controller Roland Moser Conceptual
hardware design Christian Monstein
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Development time, costs
Hardware designmanufacturing 1.4 year with 10
280h Software design 1.3 year with 10
260h System integration 0.2 year with 20
80h System tests 0.5 year with 25
250h Total 870h Material
costs SFr. 67000
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Summary

• A cheap instrument compared to PHOENIX-2, AOS
• Portable (more or less)
• Flexibel in terms of bandwidth resp. number of
  channels
• Observation of molecule lines possible
• Experience with LabView in real time environment
• Curious about scientific results
• Observation of solar radio noise in Ku-band on
  June 15th

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ARGOS related URLs

• Status ARGOS http//pisces.ethz.ch/argos/index.php
  
• More Infos http//www.astro.phys.ethz.ch/rapp/

ETH Astronomical Institute Christian
Monstein Scheuchzerstrasse 7 CH-8092
Zürich monstein_at_astro.phys.ethz.ch