Antenna arrays constructed with complex element are commonly used in radar and other communication devices. In most cases, dielectric is used as a support to keep the position of the antenna array. Without dielectric involved in an antenna array, most commercial software packages are able to simulate even a large array problem. However, it is the dielectric that makes the most commercial software package not usable because the problem size exceeds the ability of the most commercial software package. At this moment, GEMS is only one software package can be used to accurately and efficiently solve large antenna array problems. In this demo case, for a single element or array without dielectric, almost all the EM simulation software can achieve a good result, however, none of them except GEMS can simulate this array with the dielectric support. It is important that the dielectric will significantly affect the performance of antenna array in both circuit parameters and far field pattern