Abstract: The invention discloses an antenna (100, 100?, 400, 500) comprising walls in a conducting material: first (110, 410, 510) and second (120, 420, 520) main walls, a first end wall (130, 530) and a first and a second side wall. The first (110, 510) and second (120, 520) main walls extend in parallel to each other, and are joined by the first end wall (130, 530). The side walls also join the first and second main walls, so that a cavity with only one opening (105, 205, 505) is formed, a rectangular aperture which can be brought to radiate by a feed connection (207). Suitably, the antenna can also comprise a second end wall (140, 540) which extends from the second main wall (120) towards the first main wall (110), with the length of extension of the first main wall being such that the second end wall and the first main wall do not meet.

Abstract: A method and a system are disclosed compensating for failed elements in an antenna array. The method assumes that at least the amplitude and, in most cases, the phase of, at least, some of the individual elements can be controlled to some extent. If one or more of the antenna array radiating elements are failed, at least some remaining elements are used to correct for this. The amplitude and phase radiation pattern of one of the failed elements is then synthesized using K of the remaining elements. The resulting excitation from this synthesis is superimposed on the failed array excitation at the positions of the K remaining elements. This procedure can be repeated for all the failed elements using the principle of superposition.

Abstract: An antenna presenting improved polarization isolation is disclosed which presents at least two columns of rectangular micro-strip or patch elements which each has a single, linear polarization. Each column presents radiation elements of either about +45 or −45 degrees. At least two such columns are combined such that an antenna is obtained which then becomes dual polarized. Furthermore the columns are arranged such that the patches are alternately sidewise displaced to form a herringbone pattern. In other words a next patch of one column is placed on the symmetry lines through nearby patches of the other column. In this way the coupling between the patches is minimized and a high isolation is achieved between the two states of polarization. The achieved two linear states of polarization are utilized separately for polarization diversity.

Abstract: An antenna system (100) comprises a substantially planar electrically conductive ground plane (102) with an aperture (103), a substantially planar signal feed structure (104) parallel to the ground plane (102) and a substantially planar first dielectric layer (123) between the ground plane and the feed structure (104). The aperture (103) is in a shape of a first slot (105) orthogonally intersecting a second slot (106) at an intersection point (SIP). The feed structure (104) comprises a first feed unit (107) intersecting the second slot (106) asymmetrically with respect to the first slot (105), and a fork shaped second feed unit (108) comprising two feed arms (110,111). The feed arms (110,111) intersect the first slot (105) on either side of the slot intersection point (SIP), symmetrically with respect to the second slot (106).