Abstract: A waveguide network has a first port and a plurality of second ports connected to a two dimensional rectangular array of antenna elements. The second ports and antenna elements are oriented in a fixed direction. The waveguide network includes at least three successive sets of junctions and bends including a first set connected to the first port and a last set connected to the second ports. The junctions and bends in each set are all E-plane junctions and E-plane bends or are all H-plane junctions and H-plane bends, and successive sets alternate between a set of E-plane junctions and E-plane bends and a set of H-plane junctions and H-plane bends. The bends in at least one set lead in the fixed direction, and the bends in at least one other set, not including the last set, lead in a direction opposite to the first direction. Preferably, the waveguide bends in each set, other than the first set and possibly the last set, lead in a direction opposite to the bends in the previous set.
Abstract: A suspended microstrip line structure for feeding a tapered slot antenna has a ground layer separated by means of an air gap from a dielectric slab with a strip line conductor feed running on the surface of the dielectric. The strip line may run along the surface of the dielectric which faces away from the ground layer, or the structure may be inverted such that the strip line runs along the surface of the dielectric which faces the ground layer. These suspended microstrip line structures exhibit lower transmission loss. In another embodiment, a printed transmission line having a slot in its ground layer feeds a tapered slot antenna element which lies in a plane which intersects, and so is not parallel to, the printed transmission line structure. The ground layer slots cut the current on the ground of the transmission line and couple energy from the line to the tapered slot antenna element.