Abstract: The present invention provides a matched mode antenna feedline desiged to achieve simultaneous modal impedance matching with a multiple mode N-fold symmetric or N-fold polygonal antenna such as, for example, spiral antennas, sinuous antennas, modulated arm width (MAW) spiral antennas, log periodic dipole (LPDA), monopole (LPMA) arrays, and an N-fold polygonal antenna. In one embodiment, the matched mode antenna feedline (10) includes a plurality of transmission lines (20) arranged in a circular cluster around a central axis (12). Each transmission line (20) extends from an input end (22) thereof connectable with a device such as a beamformer to an output end (24) thereof connectable with an antenna feedpoint. A transition section (30) is provided between the input and output ends (22, 24) of each transmission line (20) wherein the transmission lines (20) are smoothly transitioned from a decoupled state proximal to the input ends (22) thereof to a coupled state proximal to the output ends (24) thereof.