Microwave strip transmission lines, beamforming networks and antennas and methods for preparing the same

Abstract

A novel method for producing improved RF transmission lines for satellite beamforming networks and printed circuit antenna(s) comprising the steps of (1) bonding together (a) a central conductor strip or trace comprising a dielectric layer or circuit board having on one or both surfaces thereof conductive strip circuitry; (b) upper and lower core layers of lightweight closed-cell plastic foam bonded to (a), and (c) upper and lower surface layers or faceskins of conductive metal foil or of dielectric material bonded to metal foil layers inside and/or outside, to form ground planes, bonded to the surfaces of the adjacent foam core layers. The next step involves boring a plurality of holes or vias through the ground plane layers and the core layers, and plating the bores or vias with an electroconductive metal to provide a plurality of electroconductive connections between the ground planes, for parallel plate propagating mode suppression, and to connect independent assemblies by using plated through via interconnects and quarter wavelength overlapping line interconnects to electrically connect numerous central conductor strip along with a two step bonding process, or to form a multilayer package.