Electrically thin multi-layer bandpass radome

A filter for electromagnetic waves, comprising:

• a slotted FSS ground plane layer;
• a first FSS layer disposed above said slotted FSS ground plane layer, said first FSS layer comprising a first plurality of conducting elements;
• a second FSS layer disposed above said slotted FSS ground plane layer and below said first FSS patch layer, said second FSS layer comprising a second plurality of conducting elements;
• a third FSS layer disposed below said slotted FSS ground plane layer, said third FSS layer comprising a third plurality of conducting elements;
• a fourth FSS layer disposed below said third FSS layer, said fourth FSS layer comprising a fourth plurality of conducting elements;
• a first plurality of conducting posts connecting said conducting elements of at least one of said first FSS layer and said second FSS layer to said ground plane;
• and
• a second plurality of conducting posts connecting said conducting elements of at least one of said third FSS layer and said fourth FSS layer to said ground plane.

A filter for electromagnetic waves, comprising:

• first means for artificially simulating a magnetic conductor across a selected frequency band;
• second means for artificially simulating a magnetic conductor across said selected frequency band;
• a slotted ground plane disposed between said first means and said second means;
• a first plurality of conducting vias configured to connect said slotted ground plane to at least a portion of said first means;
• and a second plurality of conducting vias configured to connect said slotted ground plane to at least a portion of said second means.

A method for filtering electromagnetic waves, comprising:

• illuminating an electromagnetic filter with an electromagnetic wave;
• reflecting a portion of said electromagnetic wave off of said electromagnetic filter to produce a reflected wave;
• and
• transmitting a portion of said electromagnetic wave through said electromagnetic filter to produce a transmitted wave, said electromagnetic filter comprising:
• a slotted ground plane layer;
• at least one upper element layer disposed above said slotted ground plane layer, said at least one upper element layer comprising a plurality of conducting elements connected to said slotted ground plane by a plurality of conducting vias;
• and
• at least one lower element layer disposed below said slotted ground plane layer, said at least one lower element layer comprising a plurality of conducting elements connected to said slotted ground plane by a plurality of conducting vias.