The electromagnetic radiation of a handset antenna to a human head model is rigorously analyzed by a new hybrid approach. In the analysis, human head is modeled by a double layered prolate spheroid with complex permittivity. A hybrid Null Field Method/Method of Moments (NFM/MoM) approach is proposed for the first time. The method is general and capable of dealing with multiple scatterers and radiators. By means of the hybrid approach, the NFM is used to model the scattering problem of the head model, and the MoM is applied to a handset antenna. The electromagnetic coupling between the head model and an antenna is taken into account by a fast convergent iteration process. Numerical results of electric field near and inside the head model and the input impedance of the antenna are calculated by the proposed hybrid approach and commercial full wave EM software. Very good agreement is obtained, which demonstrates the accuracy and efficiency of the proposed approach.
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