Antenna assembly including negative harmonic wave-ground

An antenna assembly comprising:

• a circuit board including an integrated circuit configured to process a radio frequency (RF) signal, and a conductive trace extending from the integrated circuit;
• a waveguide plate over the circuit board, the waveguide plate including a waveguide configured to guide the RF signal at least one of to and from the conductive trace;
• and
• a conductive top plate over the waveguide plate, the conductive top plate including,
• an outer surface and an inner surface facing the waveguide plate, the outer surface is opposite to the inner surface,
• a plurality of openings extending through the conductive top plate to the waveguide, the plurality of openings aligned in a first direction over the waveguide, and
• a plurality of channels defined beneath the outer surface adjacent to the plurality of openings, each one of the plurality of channels extending in the first direction and spaced apart in a second direction that is perpendicular to the first direction, and
• a plurality of ridges defining the plurality of channels, the plurality of ridges each have a maximum height that is at or beneath a plane extending across the outer surface;
• wherein the plurality of ridges include first ridges and second ridges, the first ridges are shorter than the second ridges;
• and
• wherein each one of the first ridges is between two of the second ridges.

An antenna assembly comprising:

• a circuit board including an integrated circuit configured to process a radio frequency (RF) signal, and a conductive trace extending from the integrated circuit;
• a waveguide plate over the circuit board, the waveguide plate including a waveguide configured to guide the RF signal at least one of to and from the conductive trace;
• and
• a conductive top plate over the waveguide plate, the conductive top plate including,
• an outer surface and an inner surface facing the waveguide plate, the outer surface is opposite to the inner surface,
• a plurality of slots extending through the waveguide plate to the waveguide, the plurality of slots aligned in a first direction over the waveguide, and
• receptacles defining channels recessed beneath a plane extending across the outer surface, the channels extending in the first direction parallel to the plurality of slots and spaced apart in a second direction that is perpendicular to the first direction, the channels defined by ridges extending in the first direction, each one of the ridges has a maximum height that is at or below the outer surface.