Abstract: A direct coupled resonator filter having a plurality of resonant cavities (15) such that they are separated by inner walls (18) and a coupling structure (16) couples two adjoining resonant cavities (15) since the coupling structure is located in a slot (20) defined in the inner wall (18). Thus, a portion of an edge of the slot (20) comes into electrical contact with the coupling structure (16). In general, this portion of the edge of the slot (20) corresponds to a horizontal edge surface of the inner wall (18). It should be noted that the coupling structure (16) is perpendicular to a vertical plane defined by the slot (20).

Abstract: A direct coupled resonator filter having a plurality of resonant cavities (15) such that they are separated by means of inner (18) walls and a coupling (16) means couples two adjoining resonant cavities (15) since the coupling (169 means is located in a slot (20) defined in the inner (18) wall. Thus, a portion of an edge of the slot (20) comes into electric contact with the coupling (16) means. In general, this portion of the edge of the slot (20) corresponds to a horizontal edge surface of the inner (18) wall. It should be noted that the coupling (16) means is perpendicular to a vertical plane defined by the slot (20).