A novel paradigm for high isolation in multiple antenna systems with user´s influence

In this paper, a novel paradigm is proposed to overcome the limitations posed by conventional small antenna design, exploiting the high isolation potential of narrow-band antenna systems. Several planar inverted-F antennas (PIFAs) operating in different Universal Mobile Telecommunications System (UMTS) bands are investigated, showing also the influence of different hand phantoms in average use trough Finite-Difference TimeDomain (FDTD) simulations. It is confirmed that the way a mobile phone is held is very important in determining the amount of absorption loss, detuning and antenna isolation. Narrow-band antennas are found to be more robust against mutual coupling, having therefore a better isolation.