Changes

The RF circuit analysis performed by RF.Spice is based on the assumption that your distributed RF circuit can be modeled as an interconnected network of multiport devices and transmission line segments and components. This means that all the coupling or crosstalk effects must have been captured by the S-parameter-based models of devices or by the transmission line and discontinuity models used by RF.Spice. Most of these models work satisfactorily at lower frequencies up to several Gigahertz. As the frequency increases, more complex wave radiation and propagation effects start to appear and affect the performance of your circuit. At much higher frequencies and in the millimeter wave region of the spectrum, each junction the coupling between adjacent [[Transmission Lines|transmission lines]] may have to no longer be considered as neglected. In such cases, a full-wave analysis of portions of the circuit might become inevitable. This might be especially true for junction areas and vertical interconnects that join transmission line traces on two sides of a board and across different substrate layers.