US Patent 7649505 Circularly polarized low wind load omnidirectional antenna apparatus and method

A circularly polarized, omnidirectional, corporate-feed pylon antenna uses multiple helically-oriented dipoles in each bay, and includes a vertical and diagonal support arrangement of simple structural shapes configured to provide a frame strong enough to sustain mechanical top loads applied externally. The radiators in each bay fit within the vertical supports. The radiators are integrally formed with cross-braces, and are fed with manifold feed straps incorporating tuning paddles. A single cylindrical radome surrounds the radiative parts and the vertical supports. The antenna admits of application to the upper L-band at the full FCC-allowed ERP. Beam tilt, null fill, and vertical null can be readily accommodated.