摘要 |
A wide band dual mode antenna (10) includes an electrically conductive monopole portion (12), an electrically insulating core (32) having a dielectric constant and adjacent to the monopole portion (12), and an electrically conductive wire (50) adjacent to the core (32) and having a total length associated with a first resonant frequency. The wire (50) has first and second ends (52, 54), wherein the first end (52) is electrically coupled to the monopole portion (12) and the second end (54) is electrically floating. The wire (50) includes a plurality of intercoupled segments (56, 58, 62) that are adapted to create a current null point between the first and second ends (52, 54) at a second resonant frequency to define first and second portions of the wire (50). The sum of currents in the first and second portions is substantially equal to zero at the current null point and at least some of the current in the first portion flows in a direction different from that of at least some of the current in the second portion.
|