US Patent 7142071 Broadband high-frequency slip-ring system

A velocity compensated contacting ring system includes a first dielectric material, a plurality of concentric spaced conductive rings and a first ground plane. The first dielectric material includes a first side and a second side. The plurality of concentric spaced conductive rings are located on the first side of the first dielectric material. The conductive rings include an inner ring and an outer ring. The first ground plane is located on the second side of the first dielectric material. A width of the inner ring is greater than a width of the outer ring and the widths of the inner and outer rings are selected to substantially equalize electrical lengths of the inner and outer rings.