As the Atacama Large Millimeter/submillimeter Array (ALMA) nears completion, 73 dual-polarization receivers have been delivered for each of Bands 3 (84-116 GHz) and 6 (211-275 GHz). The receivers use sideband-separating superconducting Nb/Al-AlOx/Nb tunnel-junction (SIS) mixers, developed for ALMA to suppress atmospheric noise in the image band. The mixers were designed taking into account dynamic range, input return loss, and signal-to-image conversion (which can be significant in SIS mixers). Typical SSB receiver noise temperatures in Bands 3 and 6 are 30 K and 60 K, resp., and the image rejection is typically 15 dB.
@article{arxiv.1306.6085,
title = {Development of the ALMA-North America Sideband-Separating SIS Mixers},
author = {Anthony R. Kerr and Shing-Kuo Pan and Stéphane M. X. Claude and Philip Dindo and Arthur W. Lichtenberger and Eugene F. Lauria},
journal= {arXiv preprint arXiv:1306.6085},
year = {2015}
}
Comments
Submitted to IEEE Trans. Microwave Theory Tech., June 2013. 10 pages, 21 figures