A survey of S-shape microstrip antenna elements is presented, with emphasis on theoretical and practical design techniques. Available substrate materials are reviewed along with the relation between dielectric constant tolerance and resonant frequency of microstrip patches. The S-shape antenna is first studied by a modal-expansion (cavity) technique and then is fully analyzed with wave equations. This paper presents the analysis of the electric & magnetic wave equation with the help of the numerical method. And results expressed that there is no energy loss in the propagation of wave.