Electromagnetic bandgap filter implemented in pcb with through-hole vias

A radio frequency (RF) filter formed from a printed circuit board (PCB), the RF filter comprising:

• a ground plane;
• a top conductor formed from a first layer of the PCB, the top conductor overlying the ground plane and having an input and an output for receiving and outputting signals, respectively;
• a first unit cell comprising:
• a first planar structure formed from a second layer of the PCB, the first planar structure disposed between the top conductor and the ground plane;
• a first pair of below-plane vias connecting the first planar structure to the ground plane;
• and
• a first pair of above-plane structures extending between the first planar structure and the first layer of the PCB;
• and
• a second unit cell comprising:
• a second planar structure formed from the second layer of the PCB, the second planar structure disposed between the top conductor and the ground plane;
• a second pair of below-plane vias connecting the second planar structure to the ground plane;
• and
• a second pair of above-plane structures extending between the second planar structure and the first layer of the PCB.