URSI General Assembly, Istanbul, Turkey, August 2011

URSI Commission J

  • J01.1
    • Good intro, and reasoning as to why to do this
  • J01.2
    • Calibration is a fairly hard thing, due to the ionosphere
  • J01.3
    • RFI problems for SKA-low ( Big surprise!)
    • Maybe meteor scatter, Whistlers, anomalous propagation
  • J01.4 AEE Rogers -
    • Hot noise source, custom made.
    • Can't rely on the "smoothness" of a 2-1 bandwidth antenna
  • J01.6
    • Lower frequency observing is more sensitive to magnetic fields and distortions, hence the ionospheric problems...
  • J01.7
    • Luminous quasar in EOR space.

  • JF??? Aron Parsons EOR lecture

  • J02.3
    • EVLA 74 and 330 MHz feeds
  • J02.4
    • SKA Aperture Arrays
  • J02.5
    • GMRT Sky Survey
  • J04.2 Space-based ULW Radio Astronomy
    • Overview
  • J04.3 Radio Astron talk
    • Receiving proposals for ground telescopes and tracking stations
    • Mentioned GB by name along with NZ and SA as possible tracking stations
  • J04.5 China VLBI talk
    • Satellite tracking and orbit determination with VLBI. Moon mission, possible mars mission, etc.
  • J04.6
    • VLBI for orbit determination for solar sail satellite due to constant large forces (acceleration) due to the sail
    • Wideband digital downconverter for recovering the clock tone

  • J06.1
    • Argumentation chain about whether to keep the data or not.
    • Disks are degenerating into serial devices since access speed isn't keeping up with capacity growth
  • J06.3
    • Very good talk on justification for pipelines
  • J06.4
    • Direction dependent effects
      • Ionoshpere
      • Beamshape variations
      • Meq trees
  • J06.5
    • Good talk by Rau
  • J06.6 Shapelets
    • landow-pollok theorem
    • Prolete Spheroidal bessel functions
  • J06.7
    • Imaging/cleaning/etc
    • Useful talk about using apriori information to look for signals and for cleaning images
  • J06.8
    • Use spherical instead of planar imaging.
    • Supposedly works better, due to the data shape being spheroidal to start with.
  • J06.9
    • Interference cancellation
      • Ronnie Levenda
      • Rotating field, due to earth's rotation. causes interference to appear differently in different beams
  • J06.10
    • Redundancy
      • Mutual coupling terms important, modified beamshapes of each element

URSI General Lecture

  • SMOS Passive Phased Array

URSI Commission E

  • E01.5 SE testing of small enclosures
    • Beware of near-field effect of small enclosure
    • Used spherical dipole with electronics inside it
    • Eliminates cables to the antenna which may affect readings
    • Scale results using the voltage needed to drive the antenna
    • SE = [TRPen/Ven] / TRPfs/Vfs ]
    • Should define SE in terms of transfer impedance, not loss.

URSI Commission ??

  • Analog Photonic A-D
    • See Walden Plot (R. Walden)
    • R. Williamson (2003)
    • S. Gupta (2008)
    • 7.0 ENOB at 41 GHz
    • A Khilo
    • M.e. Grein (2011)
    • Limited by M-Z non-linearities
    • DARPA W911NF-04-1-0431
    • NSF 0645960

URSI Commission A

  • A04.1
    • Up to 70% of cost of devices is in passives.
      • so use embedded passives.
    • Just test of permittivity using VNA and matallizing the sample, or compressing it in a fixture
    • Use coaxial probe if material is > 1 CM thick
    • use resonant cavity
    • Use transmission line (waveguide)
    • Use free space.
      • Sample size must be greater than 10 lambda

URSI Commission J business meetings

  • Monday
    • 19 people in Comm J died in the past 3 years
    • talked about vice-chair for next 3 yrs
    • Got vote done, Rich Bradley didn't win

Random notes:

Lorimer Bursts: whistlers, meteors, terrestrial?

Gnu radio for demodulator for RA project?
Topic revision: r1 - 2011-08-20, JohnFord
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