Antenna

In an embodiment, an antenna is disclosed. The antenna comprises: a substrate of dielectric material, the substrate being substantially planar and defining a first surface and a second surface opposed to the first surface; an electrically conductive ground plane on the first surface, the ground plane defining a slot; a first feed line configured to receive a first input signal having a frequency within an operating frequency range, the first feed line extending over the slot on the second surface in a first direction by a length of between 0.3 and 0.4 wavelengths of a signal in the operating frequency range and terminating over the slot, the first feed line being offset from a central axis of the slot running in the first direction; a second feed line configured to receive a second input signal having a frequency within the operating frequency range, the second feed line extending on the second surface in a second direction, the second direction being orthogonal to the first direction, the second feed line terminating over the slot at least a distance of 0.1 wavelengths of a signal in the operating frequency range from the first feed line such that the first and second feed lines do not intersect, the second feed line extending substantially perpendicularly from a location on an edge of the slot between 0.4 and 0.6 of the extent of that edge.