Analysis of Built-in Antennas for Handsets by the Electromagnetic Simulators

摘要

As the capacity of a personal computer and workstation increases rapidly, many electromagnetic simulators solving antenna problems are widely used. In this paper, the IE3D, FIDELITY and HFSS electromagnetic simulators, which are commercial software products, are applied to the analysis of built-in antennas for handsets in the vicinity of the human body. The IE3D, FIDELITY and HFSS electromagnetic simulators are based on the methods of moment, FDTD (Finite Difference Time Domain) and FEM (Finite Element Method), respectively. Firstly, basic characteristics including the human body's effect of a popular built-in antenna for handset such as PIFA (Planar Inverted-F Antenna) are obtained by the IE3D, FIDELITY and HFSS electromagnetic simulators, and calculated results are compared with measured results. Secondly, on the basis of newly considered design concepts for a handset antenna, a folded loop antenna for handset, which we have proposed in order to reduce the influence of the human body, is taken as an example of a balance-fed antenna and is analyzed theoretically and experimentally including the influence of the human body. In a result, calculated results by these three kinds of electromagnetic simulators are in good agreement with measured results and it is confirmed that these simulators are very effective in analyzing the handset antenna in the vicinity of the human body.