THE LOG-PERIODIC STAGGERED-FOLDED-DIPOLE ANTENNA

摘要

The log-periodic dipole antenna presents these problems. If the dipoles aresupported bytwo parallel feeder conductors, those conductors are above ground potentialand should not beconnected to the mast for lightning protection. The feeder conductors alsomust be strong and,therefore heavy, because they support the dipoles. One tactic to solve theseproblems is toconnect the dipoles to the boom through strong insulators and to feed them bya pair of crossingwires. Not only do the crossing wires not have a constant characteristicimpedance, as the feederconductors should have, this tactic also does not ground the antenna forlightning protection.These problems can be solved by using folded dipoles that have feeding pointson opposite sidesof the main conductors. This allows straight, small, feeder conductors, nostrong insulators, anddirect current paths from all conductors to the grounded mast.