A de‐embedding algorithm for electromagnetics

A “double delay” de‐embedding algorithm appropriate for electromagnetic analyses is described. This algorithm uses only two standards, a through and a double length through. By evaluating these standards, a special class of port discontinuities may be characterized and removed from the data calculated for a complete structure. Unlike related physical de‐embedding algorithms, both the characteristic impedance and the velocity of propagation of the through lines are determined. The technique described here is difficult to implement in a physical de‐embedding. The de‐embedding theory also provides a new definition of characteristic impedance, “equivalent TEM impedance,” for inhomogeneous media, such as microstrip. This new impedance exhibits a nonmonotonic dispersion which has been measured experimentally but is not seen using previous impedance definitions.