An orthogonal electrical
coupling relies on
electromagnetic coupling for the inner connection, as opposed to direct contact between conductors. A conductor on one of the lines is connected to a
ground plane which is adjacent to a resonant slot.
Microwave energy is coupled to the slot, thereby exciting the slot. A second conductor is on the opposite side of the
ground plane from the first conductor.
Microwave energy from the excited resonant slot passes to the second conductor, thereby allowing contactless
interconnection between the first conductor and the second conductor. The
coupling may emphasize certain
modes of propagation relative to other possible
modes of propagation. Specifically, the
ground plane and slot may be enclosed in a cavity of a size such that the cavity does not support any
natural mode propagation inside the cavity. Instead, the
coupling may have a cavity in which a transverse electromagnetic (TEM) mode is propagated.