ALMA Memo No. 335 Phase Drift Measurements of YIG-Tuned Oscillator Sources for the ALMA LO
نویسندگان
چکیده
In this memo, we present measured phase drift data of a YIG-tuned oscillator (YTO) multiplied to mmwave frequencies, a prototype of the baseline ALMA LO source. The test setup and analysis algorithms are described. We also discuss phase drift added by mmwave multipliers and power amplifiers, with the conclusion that their contribution is insignificant. Various components and system concepts are analyzed with respect to their contribution to the phase drift of the array. As phase drift at the level required for ALMA is unique and not well understood, much of the discussion will be of a tutorial nature.
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