Antenna beam pattern evaluation of ALMA band 9 subsystem
نویسنده
چکیده
This report describes band 9 beam pattern measurements which were made at NA ALMA front end integration center during the visit of ALMA band 9 group representatives from 2 to 7 of June 2008. The Band 9 cartridge system was mounted within ALMA front end cryostat #2 and the overall system included the cryostat window and filters. Measurement set-up, experiment condition and sequence and results of beam analysis are described. After iterative improvements, the NA FEIC measurement system was found to be adequate for beam characterization in band 9 frequency range. The measured band 9 optics beam was found to be in reasonable agreement with measurements done by band 9 cartridge manufacturer and total aperture efficiency was found to satisfy ALMA requirements.
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