PACKAGING OF ACTIVE AND PASSIVE MICROWAVE CIRCUITS USING A GRID OF PLANAR CONDUCTING ELEMENTS ON A GRID OF VERTICALLY ARRANGED SUBSTRATES

摘要

The present invention represents a new, way of packaging passive and active microwave circuits, and in particular circuits involving microstrip transmission lines and similar substrate bound transmission lines. The circuits are located between two conducting surfaces, one of these surface may be the ground plane of the microwave circuit, and at least one of these surfaces are provided with conducting elements formed as angular or curved conducting lines arranged on substrates. The conducting lines may e.g. have a zigzag shape. The two surfaces may form the bottom and lid of a cavity with conducting sidewalls. The conducting elements may with advantage be arrange in a periodic grid, and create together with the ground plane of the microwave circuit board or the smooth metal plane below the microwave circuit board a stop band for waves propagating between the lid with conducting elements and the ground plane. Thereby, cavity resonances are avoided or suppressed that otherwise create a big problem associated with the packaging in metal boxes with smooth metal walls.