Ovzon Sweden Ab

Saab Ab

Anders Ellgardt

Fredrik Holmberg

Fredrik Wester

A filter structure has a frame carrying a filter compartment that holds first and second waveguide filters (F, F; F, F). The filter compartment is rotatable a predetermined angle around a rotation axis (AV) relative to the frame so as to either engage the first waveguide filter (F, F) or the second waveguide filter (F, F) in a waveguide conduit, thus rendering the waveguide conduit adapted for forwarding radio-frequency signals at a higher band or a lower band respectively. Consequently, the filter structure is suitable for inclusion in a dual-band radio terminal for communication with spacecrafts via an antenna unit exchanging radio-frequency signals bidirectionally with the spacecrafts.

Dual-band radio terminal and filter structure

An antenna array includes an array of antenna bodies arranged on a planar structure, which, in turn, contains a circuit board with a ground-plane layer. The array of antenna bodies is arranged on a top side of the circuit board. Each of the antenna bodies is dome shaped and attached to the top side of the circuit board along its base. Each of the antenna bodies is connected to a respective top transmission line configured to convey microwave signals to and/or from said antenna bodies. The top transmission lines are further connected to bottom transmission lines via coaxial probes through the ground-plane layer. A resonance cavity is arranged below the top side of the circuit board between each of the antenna bodies. This accomplishes a highly compact design that can be produced in a cost-efficient manner.

Antenna array

An antenna including a dipole antenna element having central feeding points, a common mode rejection filter, a first length of a two-conductor transmission line, and a common mode rejection filter arranged and connected between a far end of the first length of the two-conductor transmission line and the feeding points of the dipole antenna element. The first length of the two-conductor transmission line is arranged to extend from a ground plane to a first height where the first length of the two-conductor transmission line is connected to the common mode rejection filter.

Growing community of inventors

Sundbyberg, Sweden

Anders Ellgardt