Design of Low-profile PIFA Based on Dielectric Substrate Structure

In this paper, a single band PIFA designed and simulated in High Frequency Structural Simulator (HFSS). The main body of the PIFA is completely dielectric embedded to try to make the antenna easy to conformal and have a low profile at the same time. In addition, the shorting plane is replaced with a structure composed of metallic via holes. By adjusting the length of this structure, the bandwidth, gain and profile of the antenna can be affected. The simulated results are then compared with the case that the shorting plane of PIFA is not replaced by the metallic via holes and there is some improvement in the PIFA modified with metallic via holes over the antenna without modification. The bandwidth with return loss less than −10 dB is expanded from 4.85 GHz–5.19 GHz to 4.83 GHz–5.21 GHz and the maximum gain at 5 GHz increases from 4.9 dB to 5.3 dB. This antenna serves for practical purpose such as cylindrical conformal.