Bandpass waveguide filter having iris and posts for resonating fundamental and vanes for absorbing harmonics

Claim 1

IN A RECTANGULAR WAVEGUIDE, HAVING FIRST AND SECOND NARROW WALLS AND FIRST AND SECOND BROAD WALLS, A BANDPASS FILTER COMPRISING FIRST AND SECOND INDUCTIVE IRISES EXTENDING FROM SAID FIRST AND SECOND NARROW WALLS, RESPECTIVELY, FIRST AND SECOND CAPACITIVE POSTS EXTENDING FROM APPROXIMATELY THE CENTER LINE OF SAID FIRST AND SECOND BROAD WALLS, RESPECTIVELY, SAID INDUCTIVE IRISES AND SAID CAPACITIVE POSTS BEING DISPOSED IN THE SAME TRANSVERSE PLANE TO DEFINE AN APERTURE RESONANT AT A SELECTED FREQUENCY, A PLURALITY OF VANES FORMED OF A MATERIAL WHICH WILL ABSORB MICROWAVE ENERGY, SAID VANES BEING DISPOSED PARALLEL TO AND SUBSTANTIALLY EQUIDISTANT FROM SAID BROAD WALLS, SAID VANES EXTENDING TO THE PLANE OF SAID APERTURE AND SUBSTANTIALLY TO SAID NARROW WALLS.