A simple structure for achieving low mutual coupling between two inverted-F antennas is presented. A low coupling between the antennas can be achieved by using two slits on the ground plane. The interval between the antennas can be closer than λ/8. Furthermore, this technique can be combined with other techniques. This is good for designing small handsets which need shorter intervals between antennas. In this paper, the authors present an slitted ground structure and report analysys on the mechanism the structure, where a mutual coupling of -35 dB can be achieved using the slitted ground.
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