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Cooling a low noise amplifier with a micromachined cryogenic cooler

Submitter: Roel Witvers
Description: To achieve the best possible sensitivity, radio-telescopes often have cooled electronics. By cryogenically cooling the frontend, and especially the input low noise amplifier (LNA), the system noise temperature can be reduced to the required level.

Unfortunately, cooling the frontend is not feasible for phased array telescopes. Whereas a traditional radio telescope (dish) only has one input LNA, a phased array has many. For SKA, tens of millions will be needed. Similarly, Phased Array Feeds (PAFs) have hundreds of LNAs, which can't be put into a cryostat.

But fortunately, reduction of the noise temperature (NT) is still possible if not the entire receiver is cooled, but only the first LNA.

In collaboration with the University of Twente we have tested the possibility to cool just an LNA to 100K, and measured the improvement in NT. The result of this research has now been published in "Review of Scientific Instruments". The title of the paper is "Cooling a low noise amplifier with a micromachined cryogenic cooler"


Other parties in the project where Micronit (who made the glass-coolers), Cryoz and CSIRO. This project was funded by STW.
Copyright: RH Witvers
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