The specifications of the IF filters to be used in the production radiometers are derived in a way which should provide optimum performance over a range of conditions. In addition to finding the best set of centre frequencies and bandwidths, the tolerances that can be allowed are determined, taking account of the fact that the quantities that will be used for making the phase corrections are the differences between the readings of pairs of radiometers. Other key specifications of the radiometers, such the allowable range of sideband ratios in the 183GHz mixers, are also investigated in this memo.
View a pdf version of ALMA Memo #568.
Last modified: 2007-08-31