Relation Between Reflection Phase and Surface-Wave Bandgap in Artificial Magnetic Conductors

The relationship between the phase of the reflection coefficient and the surface-wave bandgap in planar artificial magnetic conductors (AMCs) is investigated. The periodic surface of the AMC is modeled as a surface impedance and the plane-wave reflection coefficients and the supported surface waves are obtained by this model. Next, the connection between the phase of the reflection coefficient in the fast-wave region and the occurrence of bandgap in the slow-wave region is demonstrated. Theoretical results are verified numerically for two typical AMCs.