Comments on "A novel MMIC active filter with lumped and transversal elements" [with reply]

For the original article see ibid., vol.37, no.12, p.2148-53 (1989). In the above-named work, the authors present a circuit approach that represents both transversal and lumped-element filtering. Incorrect expressions for the ratio of input to output voltages, for both the low-pass section and the high-pass section, are noted by the commenter. The correct expressions for a loaded low-pass section and a loaded high-pass section are given. An additional frequency-dependent factor multiplied by the imaginary parts of eqs. (1) and (4) of the original paper is questioned. In replying, the authors state that they did not provide the details of the image parameter derivation but only gave the results. The details of this derivation are provided, and it is shown that the image parameter analysis may readily be applied to the general case.<
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