Additively manufactured mesh horn antenna

A horn antennae, comprising:

• tubular body portion including a plurality of planar wall portions, each wall portion having a plurality of holes, the plurality of wall portions forming a rectangular wavequide portion and a pyramidal horn portion,
• a stepped septum extending between two opposing wall portions of the plurality of wall portions in an internal cavity of the wavequide portion, and
• a base plate at a bottom end of the wavequide portion, partially occluding the internal cavity of the wavequide portion, and joined to three of the plurality of wall portions,
• wherein the tubular body portion, the septum, and the base plate form a single monolithic unit, and
• wherein the horn antenna has an operating frequency range and the holes of each plurality of holes are sized and arranged such that the pluralities of holes are effectively opaque in the operating frequency range.

An antenna device, comprising:

• an additively manufactured tubular body portion including a plurality of planar wall portions, each wall portion having a regular array of circular holes through the wall portion, the plurality of wall portions forming a rectangular waveguide portion and a pyramidal horn portion,
• wherein:
• each array includes a series of regularly spaced rows, the rows being alternately offset,
• each hole has a center, the centers of every two adjacent holes in a row being spaced by the same distance of less than 200 mils,
• each hole has the same diameter, and the diameter is no more than 200 mils and no less than 30 mils,
• the holes of the arrays of holes account for approximately 60 percent of the surface area of the plurality of wall portions, and
• the antenna device has an operating frequency range and the holes are sized and arranged such that the arrays of holes are effectively opaque in the operating frequency range.