Patent ID: 7659860

Claim:
An antenna arrangement comprising a dielectric medium with a first side and a second side, with conducting surface structures formed on each of said first and second sides, and in which antenna arrangement the conducting structure on the first side is a ground plane and the conducting structure on the second side is a feeding arrangement, where there is at least one slot in the ground plane, said at least one slot constituting a gap in the ground plane, where the feeding arrangement comprises at least a first, a second, a third and a fourth feeding conductor, each feeding conductor intersecting the gap of said at least one slot in the ground plane, and extending across the slot in question, passing the slot by a certain distance, said distance constituting a stub, and where each intersection constitute a feeding point for the antenna arrangement, characterized in that the feeding points are of such a number that they constitute a number of opposite feeding point pairs and where all the feeding points of the feeding arrangement are arranged for feeding the at least one slot in transmission as well as in reception, where, in a first mode of operation, at least two pairs of opposite feeding points are fed essentially in phase with each other, resulting in a first constant E-field that is directed across the slot gap, and, in a second mode of operation, the feeding points of at least one feeding point pair are fed essentially 180° out of phase with each other, resulting in a second E-field which is directed across the slot gap, having a sinusoidal variation and, in a third mode of operation, the feeding points of at least one feeding point pair, separate from the feeding point pair of the second mode of operation, are fed essentially 180° out of phase with each other, resulting in a third E-field which is directed across the slot gap, having a sinusoidal variation, where a first imaginary line, intersecting the feeding point pair of the second mode of operation, and a second imaginary line, intersecting the feeding point pair of the third mode of operation, are essentially perpendicular to each other.