Prof. Jason Glenn
This work presents the results of the testing and characterization done on a set of HEMT ampliﬁers to verify their capabilities for use in the Multicolor Submillimeter Inductance Camera (MUSIC), which is to become the primary millimeter/submillimeter camera for the Caltech Submillimeter Observatory in the coming months. We have constructed a testbed to place the ampliﬁers in the same cryogenic conditions they will experience in the MUSIC cryostat. These tests provide detailed insight into the gain and noise contribution from the ampliﬁers, and will allow for the meaningful analysis of astronomical data. Speciﬁcally, we measured the scattering parameter S21 over a range of HEMT bias settings, as well as the white noise and 1/f noise. We used these measurements to determine the bias settings best suited to our purposes. With the ideal settings in hand, we proceeded to measure the eﬀective noise temperatures of the HEMTs. The combined collection of these measurements demonstrated that all but two of the HEMTs have acceptable characteristics.
Bockstiegel, Clinton, "Testing and Characterization of HEMT Amplifiers" (2011). Undergraduate Honors Theses. 600.