A Rotman lens (12, 13) includes a first insulating layer (26) having a high dielectric constant and a second insulating layer (46) having a low dielectric constant. Metalization provided on the first insulating layer includes a lens portion (28), and metalization provided on the second insulating layer includes a plurality of transmission lines (48) and bootlace lines (52). A plurality of via openings are provided through at least one of the insulating layers, and each contain conductive material (33, 38) which electrically couples the lens portion to a respective one of the transmission lines or bootlace lines. A number of the bootlace lines physically overlap the lens portion, without electrical engagement therewith. A ground plane (63) on a further insulating layer (61) may be provided between the first and second insulating layers, in a manner free of electrical contact with the conductive material in the via openings.
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