Title :
Performance of the First ALMA Band 5 Production Cartridge
Author :
Billade, Bhushan ; Nyström, Olle ; Meledin, Denis ; Sundin, Erik ; Lapkin, Igor ; Fredrixon, Mathias ; Desmaris, Vincent ; Rashid, Hawal ; Strandberg, Magnus ; Ferm, Sven-Erik ; Pavolotsky, Alexey ; Belitsky, Victor
Author_Institution :
Group of Adv. Receiver Dev. (GARD), Chalmers Univ. of Technol., Gothenburg, Sweden
fDate :
3/1/2012 12:00:00 AM
Abstract :
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.
Keywords :
MIMIC; millimetre wave mixers; radioastronomical techniques; radiotelescopes; superconducting junction devices; superconducting microwave devices; ALMA band 5 production cartridge; Atacama large millimeter/submillimeter array; astronomy observation; frequency 16 GHz; frequency 163 GHz to 211 GHz; instantaneous RF bandwidth; superconductor-insulator-superconductor tunnel junction mixer; Amplitude modulation; Couplers; Mixers; Noise; Radio frequency; Receivers; Temperature measurement; Atacama Large Millimeter/sub-millimeter Array (ALMA); astronomy instruments; millimeter-wave mixers; superconducting devices; superconductor-insulator-superconductor (SIS) mixers; terahertz system; thin-film circuits;
Journal_Title :
Terahertz Science and Technology, IEEE Transactions on
DOI :
10.1109/TTHZ.2011.2182220