This paper presents a general method to isolate the compact dual-element antenna for mobile radio communications. The basic concept to cancel the coupling current is proposed, and two individual implemental solutions, connecting the transmission lines and the antenna elements, are illustrated respectively. Two examples targeted at 2.4 GHz ISM band have been implemented for the practical cellular phone environment. The antennas are well designed followed by the proposed principle. The result shows that the magnitude of S21 between two ports can be no higher than -10 dB in the interested bandwidth after applying the proposed methods. Good agreements are observed between measurements and simulations. It is suitable for application to mobile terminals due to its relatively low profile and good MIMO performance.
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