Patent ID: 8494820

Claim:
A computing device, comprising: a storage device; at least one processor; and an analysis unit comprising one or more computerized codes, which are stored in the storage device and executable by the at least one processor, the one or more computerized codes comprising: a parameter reading module operable to read a scattering parameters (S-parameters) file from the storage device, wherein the S-parameters file records S-parameters values measured at ports of a circuit at different signal frequencies; a vector fitting module operable to create a non-common-pole rational function of the S-parameters by applying a vector fitting algorithm to the S-parameters; a matrix conversion module operable to convert a matrix of the non-common-pole rational function to a state-space matrix; a passivity analysis module operable to substitute the state-space matrix into a Hamiltonian matrix, analyze if eigenvalues of the Hamiltonian matrix have pure imaginaries, determine that the non-common-pole rational function of the S-parameters satisfies a passivity requirement if the eigenvalues of the Hamiltonian matrix have pure imaginaries, or determine that the non-common-pole rational function of the S-parameters does not satisfy the passivity requirement if the eigenvalues of the Hamiltonian matrix have no pure imaginaries.