  We use a numerical electromagnetic simulation software to investigate a
filtering device consisting of a small dimensional microstrips embedded with a
thin layer of ferromagnetic material and we compare our results to experimental
results. We are able to show good correlation of simulation versus experiment
for the magnitude of insertion loss and phase shift. The microstrips considered
have dimensions on the order of the skin depth of the conductor and hence the
field distribution is not easily calculated by analytic methods. We show that
numerical simulation methods provide an accurate means of characterizing these
structures.
