A cavity-backed ring-slot radiator with an AMC reflector

Design results of a small, low profile printed ring-slot antenna with uni-directional radiation properties will be presented. A single linearly polarized, a dual linearly polarized, and a dual circularly polarized version of the antenna will be shown. The ring-slot antenna radiates above an open cavity loaded with an artificial magnetic conducting (AMC) reflector (see Figure 1). This work is an extension of a previously proposed cavity-backed linear slot antenna (J. Joubert, J.C. Vardaxoglou, W.G. Whittow and J.W. Odendaal, IEEE Trans AP, vol. 60, no. 2, Feb. 2012, pp. 735–742). The newly proposed ring-slot radiator is significantly smaller than the linear slot radiator, and has the ability to be fed in such a way that dual linear and dual circularly polarized radiation can be achieved.