Guided waves and negative refraction

This paper presents an analysis of a wedge-type structure comprised of RF metamaterials. The composition of the wedge is presumed to be created by unit cells arranged in rows of progressively longer lengths. At frequencies near the resonance of the unit cells, it is well known that the wedge may exhibit the type of negative refraction associated with negative index materials. The purpose of the paper is to view negative refraction from the standpoint of each unit cell contributing to a phase shift that exceeds 180 Degrees and discuss how that phase shift can lead to negative refraction. For each row of unit cells, the last cell is considered to act as a radiator.