Characteristic mode analysis for small handset antenna

The recent cellular phones including smart phone have various functions. And the built-in antennas with broadband and multi-band characteristics inside the limited space have been required. For designing the small handset antenna, the full-wave analysis method, e.g. the finite difference time domain (FDTD) method, is employed. The design goal is to meet various required performance while keeping its small size. This paper presents the characteristic mode analysis (CMA) for small handset antenna design with the excitation of the antenna.