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. ARGOS. A stronomical R eceiver G athers O uter S pace (Tyler Brulée). Double - Heterodyne - FFT - Radio - Spectrometer RAPP ETH Zürich. Minikolloquium June 11th 2002 Michael Arnold / Christian Monstein. Directory. Specifications (required / measured)

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  1. 

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

  3. 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 URL`s

  4. 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 50`000 tested • Offseterror vs temp. nil < 0.03 dB/K • Offseterror vs ac-power nil < 10 µdB/Vac • Gainerror vs temp. nil < 0.03 dB/K • Gainerror vs ac-power nil < 10 µdB/Vac • Frequency error nil < 160 ppm / < 5ppm • Timing error < 50 msec/day TBD • Power consumption nil 191W (RX only) • Sensitivity < 5 sfu 800/300 Jansky rms • System temp. < 2 dB (175K) 530/250 Kelvin • Dynamic broadband nil > 40 dB • Dynamic FFT > 24 dB ~ 50 dB • Liftime > 5 year TBD

  5. Instrument comparison Parameter ARGOS PHOENIX-2CALLISTO Receivertype FFTFrequency agileFrequency agile Frequency range 1290-1570 MHz100-4000 MHz47-862 MHz Obs.-bandwidth 250 MHz3900 MHz815 MHz Resolution (FD)  250 MHz {i}1, 3, 10 MHz110 KHz (65 KHz) Resolution (TD) > 66 msec500 µs...1sec {i}2 msec...10 sec {i} Polarization linear (vertical)L, R, I, Vlinear Sampletime/pixel 2 nsec0.5 msec2 msec (TBD) Channels 1... {ii}1...20001...12500 System temp. 250/530 K {iii}TBD {iii}TBD {iii} RMS noise 300/800 JanskyTBD {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

  6. Open day application 15.06.2002 • Possible sources: • Solar radio noise between 11,70 GHz and 12,75 GHz • Satellite signals (downlinks) • Methanol CH3OH @ 12,178 GHz ± doppler shift • Cherenkow radiation from moon due to impact of TeV cosmic particles SAT-receiver + power supply LNC Impedance matching 75/50  DC-decoupling Receiver 1415 MHz±125 MHz IF=1578 MHz

  7. 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) Option: Gorner Grat with 3m Cassegrain 210 - 820 GHz 7m antenna Bleien 100 MHz - 4 GHz

  8. Focal plane unit Ta/Cali Noise Source +35 dB ENR +28V -3 dB J2.1=PD1 Input from antenna feed PIN- switch #1 PIN- switch #2 J1.1=PD3 J1.2=PD4 J2.0 To/Texc +5V/-12V J1.0 J2.2=PD2 Termination 50 @ To=300K Preamplifier, 1-4 GHz NF 0.9dB, G +35 dB +15V/0,3A Output to receiver

  9. 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 isolator -3dB 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 IF2=IF1-Flo IF1=Fsy-Frf Frf=Fsy-IF2-Flo IF2=Fsy-Flo-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

  10. 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 Fh=1,540 GHz Frf =1,415 GHz Fl=1,290 GHz F1h=8,710GHz F1z=8,585GHz F1l=8,460GHz 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

  11. Backend hardware PC Hardware:Pentium 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

  12. Backend software

  13. Backend realtime aspects • 50`000 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

  14. 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

  15. First results Simulation of RADAR-pulses (top) and a small bandwidth, drifting signal to check cross-modulation 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 168-172 MHz < -23 dBm Telepager 400-430 MHz < - 36 dBm Citizenband 900-1350 MHz < - 24 dBm RADAR 1300-1350 MHz < -64 dBm NATEL D/GSM 1710-1855 MHz < -23 dBm max. power is 5µW (16mV @ 50)

  16. Sun-transit seen with ARGOS & PHOENIX-2 PHOENIX-2 ARGOS No background subtraction applied... FFT-spectrometer BW=spacing=500KHz Frequency agile spectrometer BW=10MHz, spacing=30MHz

  17. 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

  18. Development time, costs Hardware design+manufacturing 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. 67`000

  19. 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

  20. ARGOS related URL`s • 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@astro.phys.ethz.ch

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