Sectional meander microstrip delay line: interconnection modelling

Abstract

Model of sectional meander microstrip delay line (MMDL), which takes into account the mismatch and heterogeneity of sections, is created. Multiple sections are widely used in the planar delay lines (DL) to optimize filling the substrate area by signal conductor; for example, to achieve desired large delay, several substrates with multiple sections may be assembled and connected. Several models of the sectional DL are discussed in this paper. According to the “simplified” model a section of the transmission line (TL) is connected to the load of different impedances. This section corresponds to the single MMDL meander segment. Such model does not take into account scattering of electric field at the DL edges, and frequency dependency of characteristic impedance and phase delay of TL section. The “intermediate” models in reality are only modified the “simplified” model. To evaluate electric field scattering at the MMDL ends lumped capacitors are used in these models. Nevertheless, the frequency dependence of impedance and phase delay remains unevaluated in the “intermediate” model. The “final” model is based on hybrid analysis technique - synergy of method of moments and scattering matrixes. This model takes into account both the electric field scattering and inconsistency of sections.