Influence of Wire-Based Impedance-Matching on Helical Antenna Radiation

We investigate the influence of internal impedance-matching network for an axial-mode helical antenna on its radiation pattern. This network, proposed in our previous work, comprises a single wire attached to the helix. We show that the matching wire, mounted on a tubular dielectric support and attached to the helix close to the reflector, does not degrade the antenna radiation pattern.