An antenna, comprising: an electrically conductive ground plane (401, 505, 608, 701, 801, 901) that defines a first plane and has a first edge (402, 507, 903, 1505), an electrically conductive first ground plate (403, 501, 502, 605, 606, 702, 802, 803, 904) located on a second plane parallel to said first plane and displaced by a first distance from said first plane, said first ground plate having a second edge (404, 906) parallel to said first edge (402, 507, 903, 1505) of the ground plane (401, 505, 608, 701, 801, 901), an electrically conductive bridge (406, 607, 703, 807, 907) connecting said second edge (404, 906) of the first ground plate (403, 501, 502, 605, 606, 702, 802, 803, 904) to said first edge (402, 507, 903, 1505) of the ground plane (401, 505, 608, 701, 801, 901), an elongated first slot (407, 503, 504, 601, 602, 704, 908, 1501) delimited by at least one of said ground plane (401, 505, 608, 701, 801, 901) and said bridge (406, 607, 703, 807, 907), the longitudinal direction of said first slot (407, 503, 504, 601, 602, 704, 908, 1501) being parallel to said first edge (402, 507, 903, 1505), said first slot (407, 503, 504, 601, 602, 704, 908, 1501) being coincident with said first ground plate (403, 501, 502, 605, 606, 702, 802, 904) seen from a direction (405, 909) perpendicular to said first and second planes, and a first antenna feed point (408, 603, 604, 705, 910) on the distal side of said first slot (407, 503, 504, 601, 602, 704, 908, 1501) seen from the center of said ground plane (401, 505, 608, 701, 801, 901), wherein the dimensions of said first ground plate (403, 501, 502, 605, 606, 802) are such that its length in said longitudinal direction is equal to at least one of: a half wavelength of electromagnetic radiation at an operational frequency of said antenna, the length of said first slot (407, 503, 504, 601, 602, 704, 1501) in said longitudinal direction, and its width in a direction perpendicular to said longitudinal direction is between 3 and 10 millimeters. an electrically conductive ground plane (401, 505, 608, 701, 801, 901) that defines a first plane and has a first edge (402, 507, 903, 1505), an electrically conductive first ground plate (403, 501, 502, 605, 606, 702, 802, 803, 904) located on a second plane parallel to said first plane and displaced by a first distance from said first plane, said first ground plate having a second edge (404, 906) parallel to said first edge (402, 507, 903, 1505) of the ground plane (401, 505, 608, 701, 801, 901), an electrically conductive bridge (406, 607, 703, 807, 907) connecting said second edge (404, 906) of the first ground plate (403, 501, 502, 605, 606, 702, 802, 803, 904) to said first edge (402, 507, 903, 1505) of the ground plane (401, 505, 608, 701, 801, 901), an elongated first slot (407, 503, 504, 601, 602, 704, 908, 1501) delimited by at least one of said ground plane (401, 505, 608, 701, 801, 901) and said bridge (406, 607, 703, 807, 907), the longitudinal direction of said first slot (407, 503, 504, 601, 602, 704, 908, 1501) being parallel to said first edge (402, 507, 903, 1505), said first slot (407, 503, 504, 601, 602, 704, 908, 1501) being coincident with said first ground plate (403, 501, 502, 605, 606, 702, 802, 904) seen from a direction (405, 909) perpendicular to said first and second planes, and a first antenna feed point (408, 603, 604, 705, 910) on the distal side of said first slot (407, 503, 504, 601, 602, 704, 908, 1501) seen from the center of said ground plane (401, 505, 608, 701, 801, 901), wherein the dimensions of said first ground plate (403, 501, 502, 605, 606, 802) are such that its length in said longitudinal direction is equal to at least one of: a half wavelength of electromagnetic radiation at an operational frequency of said antenna, the length of said first slot (407, 503, 504, 601, 602, 704, 1501) in said longitudinal direction, and its width in a direction perpendicular to said longitudinal direction is between 3 and 10 millimeters.