DRA antennas have several favorable characteristics such as small size, low cost and desirable radiation pattern. These advantages make companies use this antenna in different fields in communication. Our aim is to enhance some properties of the rectangular antenna such as gain, bandwidth, S-parameter, VSWR and directivity. Therefore, three kinds of rectangular DRA antenna designs were selected and their geometrical and material parameters were systematically changed to enhance their performance. Also, the effect of adding more layers into the DRA design to get higher gain and to enhance the efficiency at frequency 28 GHz was studied. The designing and simulating of the DRA antenna were carried out by using the framework of CST.