Unidirectional, asymmetric, e-skid, waveguide grating antenna

A waveguide grating antenna apparatus comprising

• a substrate layer;
• a lower waveguide array layer upon the substrate composed of a plurality of first waveguides extending axially and a plurality of second waveguides extending axially and arranged in parallel and alternating in position with the plurality of first waveguides across the lower waveguide array layer in which
• each first waveguide is of a first maximum width;
• and
• each second waveguide is of a second maximum width narrower than the first maximum width and is spaced apart from each adjacent first waveguide;
• and
• an upper waveguide array layer positioned above the lower waveguide array layer composed of adjacent, separated elements extending axially along each first waveguide and each second waveguide,
• wherein each first waveguide is composed of a center ridge and two lateral ridges extending along and spaced apart from each side of the center ridge such that gaps are formed between the center ridge and each lateral ridge.