Computer-aided tuning of highly lossy microwave filters using complex coupling matrix decomposition and extraction

Lossy filters have broad applications in satellite communication systems. This paper proposes an efficient tuning method, based on complex coupling matrix decomposition and extraction, for highly lossy filters. Interestingly, it shows that the proposed decomposition technique preserves the scattering parameters of the original coupling matrix. A simple and efficient tuning algorithm is provided and illustrated with a four-pole lossy Chebyshev filter example. The experimental demonstration is finally presented to validate the proposed tuning technique.