Radiation pattern characterization of single patch spiral resonator (SR) structure using linear array approach

Spiral resonator (SR) structure is used in many microstrip antenna design due to its unique properties, such as negative permeability value as an artificial magnetic inclusion. This paper present the formulation of the radiation pattern of the microstrip antenna with single patch SR shaped structure using linear array model of n nonisotropic similar point sources. The linear array is assumed by modeling of each stripline of the spiral with length l and width w as a nonisotropic point source. The result of this approach is compared to the simulation result through CST software and it shows the similarity between both results for the same N. Moreover, with both w and s are constant; the radiation level tends to increase with the increasement of N.