Vents with signal image for signal return path

An electrical structure, comprising:

• a dielectric substrate having a metal signal line therein;
• a first metal voltage plane laminated to a first surface of the dielectric substrate, wherein the first metal voltage plane includes an opening, wherein an image of a first portion of the metal signal line projects across the opening in the first metal voltage plane, and wherein a first electrically conductive strip across the opening in the first metal voltage plane includes the image of the first portion;
• and
• a second metal voltage plane laminated to a second surface of the dielectric substrate, wherein the second metal voltage plane includes an opening, wherein an image of a second portion of the metal signal line projects across the opening in the second metal voltage plane, and wherein a second electrically conductive strip across the opening in the second metal voltage plane includes the image of the second portion, wherein a signal current is flowing through the metal signal line, wherein a first return current is flowing through the first electrically conductive strip, wherein a second return current is flowing through the second electrically conductive strip, wherein the signal current is an alternating current, wherein the first return current includes a first portion of the signal current, and wherein the second return current includes a second portion of the signal current.