Details

Autor(en) / Beteiligte

• Billade, B.
• Nystrom, O.
• Meledin, D.
• Sundin, E.
• Lapkin, I.
• Fredrixon, M.
• Desmaris, V.
• Rashid, H.
• Strandberg, M.
• Ferm, S.
• Pavolotsky, A.
• Belitsky, V.

Titel

Performance of the First ALMA Band 5 Production Cartridge

Ist Teil von

• IEEE transactions on terahertz science and technology, 2012-03, Vol.2 (2), p.208-214

Ort / Verlag

IEEE

Erscheinungsjahr

2012

Quelle

IEEE Xplore

Beschreibungen/Notizen

• We present performance of the first ALMA Band 5 production cartridge, covering frequencies from 163 to 211 GHz. Atacama Large Millimeter/sub-millimeter Array (ALMA) Band 5 is a dual polarization, sideband separation (2SB) receiver based on all Niobium (Nb) superconductor-insulator-superconductor (SIS) tunnel junction mixers, providing 16 GHz of instantaneous RF bandwidth for astronomy observations. The 2SB mixer for each polarization employs a quadrature configuration. The sideband separation occurs at the output of the IF hybrid that has integrated bias-T for biasing the mixers, and is produced using superconducting thin-film technology. Experimental verification of the Band 5 cold cartridge performed together with warm cartridge assembly, confirms that the system noise temperature is below 45 K over most of the RF band, which is less than 5 photon noise (5 hf/k). This is to our knowledge, the best results reported at these frequencies. The measurement of the sideband rejection indicates that the sideband rejection is better than 10 dB over 90% of the observational band.