Circuit and method for suppression of electromagnetic coupling and switching noise in multilayer printed circuit boards

A printed circuit board (PCB) comprising:

• a power distribution network including a periodic structure integral with a parallel-plate waveguide operative to define a stopband at frequencies of interest, the periodic structure including
• an upper conductive plate,
• an array of conductive coplanar patches positioned a distance t2 less than 0.5 mm from the upper conductive plate, the distance t2 chosen to optimize capacitance between the conductive coplanar patches and the upper conductive plate for suppression of noise over the stopband,
• a lower conductive plate;
• and
• conductive vias contained in a dielectric layer, the vias extending from respective patches to the lower conductive plate.

A transverse electromagnetic mode suppression apparatus comprising:

• a first conductive plate;
• a second conductive plate;
• an array of first conductive patches oriented substantially parallel to the first conductive plate and spaced a distance t2 therefrom;
• an array of second conductive patches oriented substantially parallel to the second conductive plate and spaced a distance t2 therefrom;
• an array of first vias, one end of each first via electrically contacting the first conductive plate, another end of each first via electrically contacting a respective second conductive patch;
• and
• an array of second vias, one end of each second via electrically contacting the second conductive plate, another end of each second via electrically contacting a respective first conductive patch, lengths of the first vias and the second vias and the distance t2 chosen so that the transverse electromagnetic mode suppression apparatus suppresses imparted electromagnetic energy at frequencies of interest.

A coaxial waveguide comprising:

• an outer conductor;
• an inner conductor;
• an array of circumferential patches, respective patches spaced from adjacent patches by circumferential gaps;
• a first dielectric material separating the inner conductor from the circumferential patches;
• a second dielectric material separating the circumferential patches from the outer conductor;
• and
• vias positioned in the first dielectric material, respective vias electrically connecting respective circumferential patches with the inner conductor.

Apparatus for suppressing noise in an electrical device, the apparatus comprising:

• an upper conductive plate;
• an array of conductive coplanar patches;
• a lower conductive plate separated from the array of conductive coplanar patches by a dielectric layer;
• and
• conductive rods connecting patches to the lower conductive plate, at least one of the patches connected to the lower conductive plate by multiple conductive rods.