A Fast and Reliable Method For Computer Analysis of Microwave Mixers (Comments)

In Section IV of the above paper, Schiippert expressed conversion properties of the pumped diode junction in formulas (41)--(44). In general, that description does not satisfy well-known theory (e.g., [1], [2]). The subscript notation for the coefficients of the conversion admittance matrix used by Schüppert in formulas (42) and (44) is inauspicious, and it is probably a source of the mistaken form of the conversion matrix in formula (41).