State Space Modelling of Microstrip Lines

Microstrip transmission lines are a specific type of transmission lines in the high frequency (HF) regime. Such microstrips are commonly used for test fixtures in HF-measurements, e.g. for broadband characterization of HF - devices. For accurate measurement of the device under test (DUT), a priori knowledge of the frequency behaviour of the microstrip line is needed. In the present work, a broadband state space model for microstrip transmission lines is proposed. The equivalent circuit parameters of the microstrip are extracted by means of quasi-3D finite element simulations.