An analytical diagnosis of general Chebyshev narrow-band coupled resonator filters

A novel analytical filter diagnosis technique, based on the partial fraction expansions of admittance matrix, is proposed in this paper. The technique is applicable to computer aided filter tuning of a general Chebyshev filter. The key issue in the proposed technique is a new concept for removing the phase loading effect. This is accomplished by extending the realizability conditions to the asynchronously tuned filters. Using this analytical diagnosis technique, the inherent dispersions of the resonators and coupling elements are compensated by stray couplings in the diagnosed filter models. The filter topology that can be handled by this technique is only limited by the availability of the exact filter synthesis technique, with which the filter to be diagnosed is designed.