Comparative analysis of the Curnow and Malykhin-Konnov-Komarov (MKK) circuits as representations of coupled-cavity slow-wave structures

Two lumped element models of coupled-cavity slow-wave structures, one due to Curnow (1965) and another due to Malykhin, Konnov, and Komarov (MKK) (2003), are compared. The basis of comparison is the level of accuracy with which the models reproduce the cold circuit phase velocity and characteristic impedance of the structures as functions of frequency, as obtained from numerical solutions of Maxwell\´s field equations. Two distinct types of coupled-cavity structure are analyzed using these two models. These are a C-band double staggered ladder circuit and an L-band slot coupled "Hughes-type" structure. We find for the C-band case, both the Curnow and MKK models give excellent representations of both the cavity and slot bands, but for the L-band case the Curnow model has no solution when an attempt is made to fit both the cavity and slot bands, while the MKK model accurately represents both bands in this case.