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NRAO-GB Support for VSOP-2

NRAO-GB Support for VSOP-2. Glen Langston National Radio Astronomy Observatory Green Bank, WV USA NRAO Goals Support Space VLBI Science Develop Systems for integration into future Ground Science systems. Bi-Static Radar. 0°. 0°. Technology Development: “Chalmers” Feed.

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NRAO-GB Support for VSOP-2

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  1. NRAO-GB Support for VSOP-2 • Glen Langston National Radio Astronomy Observatory Green Bank, WV USA NRAO Goals • Support Space VLBI Science • Develop Systems for integration into future Ground Science systems Glen Langston: VSOP-2 at JPL 06

  2. Bi-Static Radar Glen Langston: VSOP-2 at JPL 06

  3. 0° 0° Technology Development: “Chalmers” Feed Low Band (150 to 1700 MHz) Feed 1 meter x 1 meter square. Dewar Low Band vertical 180° Low Band Horizon 180° Signal Inject Feed Advantages: Wide Bandwidth 150 to 1700 MHz Focus position independent of Wavelength 60 degree FWHM illumination pattern Professor Per-Simon Kildal Glen Langston: VSOP-2 at JPL 06

  4. MEMIO IPAT TOD MEMIO Gigabit Ethernet Data Acquisition System 3.6 TB/ch Fixed Storage (JBOD) Re-Order Data (non-real time) 3.2 TB/ch Removable Storage Disk Controller (400 MB/s/ch max) Polyphase Channelization 52 sb 75 MHz 135-270 MB/s (w/compression) 140 MHz IF 75 MHz BW 70 dB SFDR 186 MS/s 12 bits NRAO Antenna VMETRO 5210-JFF Conduant TK-200 RX A/D 5210-JFF TK-200 RX A/D RX A/D TK-200 5210-JFF RX A/D Fibre Channel Fibre Channel FPDP II VME NRAO LAN RX Computer 5210-JFF TK-200 FPDP SBC Firewall VMETRO EL-SB2G MIT/LL GPS/IRIG Control Computer Glen Langston: VSOP-2 at JPL 06

  5. ISIS six element Passive radar Installed ISIS six element discone antenna array for passive VHF signal capture at NRAO Green Bank, with the 43 meter antenna and the Lincoln Labs trailer seen in the background. The MIDASMobile #001 node is installed in the left hand side of the trailer. Low loss heliax cable is attached to each VHF discone antenna (right image) and secured to the mounting poles, while nylon cord provides guying support and structural stability. Glen Langston: VSOP-2 at JPL 06

  6. Passive (FM radio) Radar Observation of scattering of 107.3 MHz FM intercepted at MIT Haystack Observatory and detected atNRAO Green Bank using the passive radar mode of the ISIS Hardware at both sites. The detection distance is 800+/-2 km with an expected direct propagation path of 798 +/- 1 km. Such a propagation path is most likely due to a forward scatter event from a meteor. Glen Langston: VSOP-2 at JPL 06

  7. GBT • Operation at 0.3 to 49 GHz • Dedicated participation High Sensitivity Array VLBI Glen Langston: VSOP-2 at JPL 06

  8. 20m • Operation at 2 to 9 GHz • Surface RMS .8mm • Prime focus optics • VLBI antenna • Fast 2deg/second Glen Langston: VSOP-2 at JPL 06

  9. Costs • $$$ Antenna • $$ Design Engineer • $$ Software • $ Individual Modules (but these add up…) Glen Langston: VSOP-2 at JPL 06

  10. Weather/Opacity vs frequency • Opacity is similar (factor of 2) at 26 and 38 GHz • GB has daily weather model • Bad weather today…. Glen Langston: VSOP-2 at JPL 06

  11. Weather/Opacity vs time Glen Langston: VSOP-2 at JPL 06

  12. Antenna Signal Path • All Items JAXA/ISAS • Feed NRAO/Caltech • Receiver NRAO/Caltech/All • Satellite Sim. JAXA/Custom • Transmitter Commercial • Timing Tone Custom/Commercial • Phase Measurement Custom/Commercial • Demodulator Commercial • Decoder Commercial/Software • Recorder Mk V/Commercial • Data Extraction NRAO/Custom • Monitor Custom • Schedule Custom Glen Langston: VSOP-2 at JPL 06

  13. NRAO Contributions/Interests • $$$ Antenna • $$ Software • $ Low Noise Front Ends • $ Uplink/Downlink phase control/detection • $ Software Back Ends (real-time spectra/calibration of VSOP-2 data) • Test correllation • Transient Searches • Continuum imaging • Galactic molecules Glen Langston: VSOP-2 at JPL 06

  14. Molecule/Transient Survey • Technology has advanced. • Digital Spectra Pulsars and Transients in 1 backend • Transients at 43GHz • High Stability • Molecule Survey • All Sky coverage Glen Langston: VSOP-2 at JPL 06

  15. Conclusions • The NRAO in GB Supports the Science Goals of the VSOP-2 Mission. • GB will support GBT Science Observations of successful proposals. • The NRAO in GB is willing to support VSOP-2 Ground Tracking. • NRAO’s top ground tracking priority • Develop technology and software for spacecraft tracking that has applications for GB science operations. Glen Langston: VSOP-2 at JPL 06

  16. Ionospheric Incoherent Scatter First light detection of bistatic incoherent scatter from the F region ionosphere on a Millstone Hill toNRAO Green Bank forward path on 25 January 2006, at the common volume intersection point in geodeticcoordinates: (40 deg lat, 283 deg lon, 300 km altitude). The upper data was collected using the reference MillstoneHill software radar platform in a monostatic configuration, while the lower data was collected on the MIDASMobile#001 platform at NRAO Green Bank. An uncoded 480 usec pulse was transmitted from Millstone Hill,resulting in a predicted and subsequently observed bistatic signal to noise ratio of 21 dB. Although the bistaticreturn appears to be approximately 80 km long in range, the actual ionospheric altitude resolution (set by commonintersection volume size) is 10 km. Glen Langston: VSOP-2 at JPL 06

  17. ISIS Hardware: MIDAS-Mobile 16U SKB Shock rack Enclosure Zyfer L1 GPS Frequency reference and oscillators : NTP, PPS, Modular and Expandable 2 Echotek Digital Receiver cards (3 analog channels each, 14 bit ADC, digital down converters) 4 Dual CPU computers per node (2 RX hosts, 2 processing), 500 GB per computer (2 TB total) Gigabit Network Switch for data interconnect, uplink, and expansion 1500W UPS system, N-connector Cables, linear power supply All elements monitored and controlled via Ethernet Glen Langston: VSOP-2 at JPL 06

  18. Recent Test Data Obtained Glen Langston: VSOP-2 at JPL 06

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