Ultra-low-profile triaxial low frequency antenna for integration in a mobile phone, including: • a magnetic core, made of a soft-magnetic non-electro conductive material, including four corner protuberances defining two orthogonal winding channels around the magnetic core; • X-winding, Y-winding and Z-winding of conductive wire orthogonal to one another wound around X-axis, Y-axis and Z-axis (X, Y, Z) orthogonal to each other surrounding said magnetic core, the X-winding and the Y-winding being arranged in said two winding channels of the magnetic core and the Z-winding being arranged surrounding the four corner protuberances, such that when an electromagnetic field cross over the mentioned X- Y- and Z-windings (DX, DY, DZ), an electric potential is generated between each wire ends; wherein each of the X-, Y- and Z-windings (DX, DY, DZ) has a conductive wire entry and a conductive wire exit connected to a respective connection terminal, wherein the antenna further comprises a first soft-magnetic sheet perpendicular to the Z-axis and attached superimposed on to flat faces of the four corner protuberances of the magnetic core, said flat faces being perpendicular to the Z-axis and protruding from the winding channels defined between said four corner protuberances in a side facing the first soft-magnetic sheet, the X-winding and the Y-winding wound in said winding channels becoming partially covered by said first soft magnetic sheet, whereby the X-winding and the Y-winding are partially confined between the magnetic core and the first soft magnetic sheet, and wherein the first soft-magnetic sheet is bigger than the magnetic core in the X-axis and in the Y-axis directions, and wherein the first soft-magnetic sheet covers at least partially the Z-winding, such that the first soft-magnetic sheet provides a limiting edge for the Z-winding, so that an increase of the sensitivity of the Z-winding and a reduced thickness of the antenna in the Z-axis direction are obtained. • a magnetic core, made of a soft-magnetic non-electro conductive material, including four corner protuberances defining two orthogonal winding channels around the magnetic core; • X-winding, Y-winding and Z-winding of conductive wire orthogonal to one another wound around X-axis, Y-axis and Z-axis (X, Y, Z) orthogonal to each other surrounding said magnetic core, the X-winding and the Y-winding being arranged in said two winding channels of the magnetic core and the Z-winding being arranged surrounding the four corner protuberances, such that when an electromagnetic field cross over the mentioned X- Y- and Z-windings (DX, DY, DZ), an electric potential is generated between each wire ends; wherein each of the X-, Y- and Z-windings (DX, DY, DZ) has a conductive wire entry and a conductive wire exit connected to a respective connection terminal, wherein the antenna further comprises a first soft-magnetic sheet perpendicular to the Z-axis and attached superimposed on to flat faces of the four corner protuberances of the magnetic core, said flat faces being perpendicular to the Z-axis and protruding from the winding channels defined between said four corner protuberances in a side facing the first soft-magnetic sheet, the X-winding and the Y-winding wound in said winding channels becoming partially covered by said first soft magnetic sheet, whereby the X-winding and the Y-winding are partially confined between the magnetic core and the first soft magnetic sheet, and wherein the first soft-magnetic sheet is bigger than the magnetic core in the X-axis and in the Y-axis directions, and wherein the first soft-magnetic sheet covers at least partially the Z-winding, such that the first soft-magnetic sheet provides a limiting edge for the Z-winding, so that an increase of the sensitivity of the Z-winding and a reduced thickness of the antenna in the Z-axis direction are obtained.