Method of constructing multiple-frequency dipole or monopole antenna elements using closely-coupled resonators

Abstract

Abstract A multiple-frequency monopole or dipole antenna or antenna element that exhibits resonance at multiple arbitrary predetermined frequencies at a single feedpoint includes a driven conductor operative on a first arbitrary predetermined frequency and including a feedpoint. A number n of additional non-driven conductors, wherein n is at least one, resonant at respective n arbitrary predetermined frequencies different from the first frequency are disposed in substantially parallel spaced relationship at a predetermined spacing to electromagnetically couple the driven and non-driven conductors and produce a non-reactive impedance at the feedpoint at the first and at each n additional frequency. Preferably, the predetermined spacing of the driven and non-driven conductors is determined according to the equation: ##EQU1## where d 1n is the spacing on centers between the driven and non-driven conductors, expressed in wavelengths at the n frequency, D is the diameter of the driven and non-driven conductors, expressed in wavelengths at the n frequency, Z 0 is the desired impedance at the n frequency when the antenna element is a dipole, or twice the desired impedance when the antenna element is a monopole, F 1 is the resonant frequency of the driven conductor, and F n is the resonant frequency of the n non-driven conductor.

Inventors

• 👤 Gary A. Breed

Bibliographic Details