A planar multi-layer transreflector for generating collimated coherent
energy comprises one or more of insulating layers between two or more
metallic layers. The transreflector substantially reflects a
cross-polarized component of an incident millimeter-wave signal and
substantially transmits the remaining portions of the incident
millimeter-wave signal. Each of the metallic layers comprises a plurality
of rectangles arranged in a grid pattern radially varying in size within
circumferential regions. The reflected cross-polarized component may be
substantially orthogonal to the transmitted remaining portions. A
substantially collimated and coherent wavefront comprising the remaining
portions may be produced in a first direction, and substantially
collimated and coherent wavefront comprising the cross-polarized
components may be produced in a second direction.