| 摘要 |
A multiple resonance antenna 100-1 comprises a tubular body110 with one closed end and one open end. The open end of the tubular body includes a female thread region 116 into which a further body 130 with a male thread region 132, 134 engages. The said further body 130 includes a cover 136 for closing the open end of the tubular body and when the said bodies 110-1, 130 are engaged they form a closed space. A first radiator 140 extends in a longitudinal direction within the closed space of the tubular body and extends through the cover 136 of the further body 130. A second radiator 120 is disposed around the first radiator 140. A liquid radiator 150 is also housed within the said closed space. The first radiator 140 may be surrounded by a dielectric block of material which may be a further radiator and an external feed point 142 may be provided. The closed space may be subdivided into regions which receive different polar liquid radiators with different additives. The first and/or second radiators 140, 120 may be directly fed or parasitically fed. The second radiator 120 may be a helical element located within the threaded regions of the bodies or within the said closed space. A liquid tight seal 160 may be provided between the bodies. The antenna may provide a compact arrangement which can operate in wide and/or a low adjustable frequency bands. |
